electronics engineering compilation

8/10/2019 Electronics Engineering COMPILATION

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When a motor is overloaded, it will usually

A.

Overheat

B. Slow downC. Speed upD. Vibrate

Which motor that produces the highest increase in torqueconsidering the same increase in current?

A. Dc shunt

B.

Dc series

C. Cumulatively compoundedD. Diferentially compounded

Calculate the dc-voltage at the output of a half-waverectifier with a 12Vrms input?

A. 2.7 VB. 3.8 V

C. 4.5 V

D.

5.4 V

To minimize arcing during starting of dc motors, aresistance should be added to limit the current in the _____.

A. Series field windingB. Shunt field winding

C.

Armature Winding

D. All of these

When a dc motor has no load, what will happen to the backemf?

A. ReducesB. Increases

C.

Becomes maximum

D. Becomes zero

When can we get a maximum mechanical power from a dc

motor?

A. Eb = 0

B.

Eb = ½ V

C. Eb = 1 VD. Eb = 2 V

The torque of a dc motor is

A. Directly proportional to the field strengthB. Inversely proportional to the field strength

C. Directly proportional to the armature current

D.

A and C are correct

What is the most common method used in varying the

speed of a dc motor?

A. By varying the supply voltageB. By changing the effective number of conductors

in seriesC. By varying the armature resistance

D. By varying the field strength

A motor whose speed increases as the load is increased.

A. Series DCB. Dc shuntC. Cumulatively compounded

D. Differentially compounded

In applications where an almost constant speed is required,a _____ motor is a good choice.

A.

Dc shunt

B. Dc seriesC. Cumulatively compoundedD. Diferentially compounded

In applications where a high torque is needed duringstarting a ______ motor is preferred.

A. Dc shunt

B.

Dc series

C. Cumulatively compounded

D. Diferentially compounded

In applications where sudden heavy loads happen for shortduration, a ______ motor is the best choice.

A. Dc shuntB. Dc series

C.

Cumulatively compounded


In motors of the same rating, which has the least startingtorque?

A.

Dc shuntB. Dc series

C. Cumulatively compounded


What is the average voltage of an alternating voltage, v =

100sin120πt?

A.

0 (zero) VB. 31.8 V

C. 63.6 VD. 70.71 V

A semiconductor diode that is called a “cat-whisker”?

A.

Point-Contact Diode

B. Diac

C. PIN diode

D. Thyrector

Calculate the peak-to-peak ripple voltage of a 20 V full-

wave power supply with a filter capacitor C = 220 µF whendelivering a load current of 50 mA.

A.

2.0 Vpp

B. 3.79 VppC. 5.67 VppD. 7.9 Vpp



A 12 VDC power supply is regulateed using 7805IC and isused as TTL circuits that require a 0.2 amps current.Determine the dropout voltage of the system.

A. 4 VB. 5 V

C. 6 V

D.

7 V

Semiconductor-based, volatile data storage device that can

be written and read randomly.

A.

RAM

B. PROM

C. EPROMD. EEPROM

The production of an emf in a circuit composed of two

dissimilar metals when their two junctions are at differenttemperature

A.

Seebeck effect

B. Peltier EffectC. Thomson EffectD. None of the above

Semiconductor device that composed of two diodes inseries with opposite direction

A. Point-Contact DiodeB. Diac

C. PIN diode

D.

Thyrector

A cell that cannot be recharged is:

A. A dry cell.

B. A wet cell.C. A primary cell.D. A secondary cell.

A direct short-circuit of a battery can cause:

A. An increase in its voltage.B. No harm other than a rapid discharge of its

energy.C. The current to drop to zero.

D.

An explosion.

A cell of 1.5 V supplies 100 mA for seven hours andtwenty minutes, and then it is replaced. It has supplied:

A. 7.33 Ah.B.

733 mAh.C. 7.33 Wh.D. 733 mWh.

The energy in a cell or battery depends mainly on:A. Its physical size.B. The current drawn from it.

C. Its voltage.D. All of the above.

In which of the following places would a transistor battery be the best power-source choice?

A. A heart pacemaker.B. An electronic calculator.C. An LCD wristwatch.D. A two-way portable radio.

In which of the following places would you most likelychoose a lithium battery?

A.

A microcomputer memory backup.B. A two-way portable radio.C. A portable audio cassette player.

D. A rechargeable flashlight.

Where would you most likely find a lead-acid battery?

A. In a portable audio cassette player.

B. In a portable video camera/recorder.C. In an LCD wall clock.D. None of the above

Which kind of battery should never be used until it “dies”?

A. Silver-oxide.

B. Lead-acid.

C. Nickel-cadmium. D. Mercury.

The current from a solar panel is increased by:

A. Connecting solar cells in series.B. Using NICAD cells in series with the solar cells.

C. Connecting solar cells in parallel. D. Using lead-acid cells in series with the solar cells.

An interactive solar power system:

A. Allows a homeowner to sell power to the

utility.B. Lets the batteries recharge at night.

C. Powers lights but not electronic devices.D. Is totally independent from the utility.

One reason why it is impractical to make an extremely

high-voltage battery of cells is that:

A. There’s a danger of electric shock.

B. It is impossible to get more than 103.5 V withelectrochemical cells.

C. The battery would weigh to much.

D.

There isn’t any real need for such thing.

The production or absorption of heat at the junction of twometals when current is passed through the junction

A. Seebeck effect

B.

Peltier EffectC. Thomson EffectD. None of the above



One causes why the shaft torque is less than the developedarmature torque of a dc motor.

A. Eddy currentB. Field lossC. Brushes loss

D.

Friction loss

The main purpose of an instrumentation amplifier is _____.

a. To compare input signals.

b.

To amplify small signals that are riding

on large common mode voltages.

c. To reject unwanted signals.

d. To trim small signals that are riding on largecommon mode voltages.

In a series RLC circuit, what is the condition of the circuitif there is high impedance, low current, and low reactancevoltages?

e. Ideal circuit

f. Percent circuitg. Resonant

h.

Non-resonant

• The most accurate type of test equipment used for

measuring high power is the _____.a. Bolometer

b. Wavemeter

c.

Calorimeter

d. Wattmeter

• The effect on the human body of 21-20 mill-amperes, 60 Hz A.C. or 80-?? milli-amperes D.C is

______.a. Respiratory failure

b.

Mascular inhibitionc. Reflex action

d. Surprise

• A straight line plot of collector current Ic and Vcefor a transistor circuit is called the _____.

a. Threshold line

b.

DC loadline

c. Loading limitd. Linear level

• If a transformer has a turns ratio of 1:3, what is thecurrent ratio?

a. 1:3

b. 1:9

c.

3:1d. 9:1

• There is a _____ degrees of inversion between gateand drain voltages of an FET.

a. Zero b. 90

c. 180d. 270

• A differential circuit uses a _____.

a. Capacitor in its feedback circuit b. RLC in its feedback circuitc. Inductor in its feedback circuit

d.

Resistor in its feedback circuit.

•

Which of the following shells contain 2 electrons?a. L

b. Nc. M

d.

K

• What amplifier is used when power from a

convertion servoamplifier is too small to drive largeservomotors (either A.C or D.C.)?

a. Differential amplifier

b. RD amplifierc. Audio amplifierd. Operational amplifier

• An amplifier which is designed to be used withother circuit component to perform either

computing functions or some type of transferoperation?

a. Differential amplifier b. RD Amplifier

c. Audio amplifier

d. Operational amplifier

• What type of LC oscillator is sometimes called a“tickler” oscillator in reference to the transformersecondary or tickler coil that provides the feedback

to keep the oscillator going?a. Colpitts

b. Clapp

c.

Armstrong

d. Hartley

• The ratio of the DC collector current Ic to the

emitter current Ie is called the DC ______.a. Delta

b. Beta (Bdc)c. Echo

d.

Alpha (Adc)

• The effect of 60 Hz A.C. over 100 mA or DC over

300 mA on the human body.a. Mascular inhibition

b. Respiratory failurec. Surprise

d.

Usually fatal

• The bit storage capacity of a Read Only

Memory(ROM) with a 512 x 8 organization is _____ bits.

a. 1024

b. 8192

c. 4096d. 2048



• The device used to produce a gradual chance of

impedance at the end of a waveguide is called a _____.

a. Funnel b. Load

c. Dummy

d. Horn

• In a robots, he axis that allows rotation are oftenreferred to as _____ joints

a.

Revolving

b. Revolutec. Resoluted. Rotary

• The most widely used combination bias system in basic transistor amplifier

a. Limited type b. Current divider type

c.

Voltage-divider typed. Base current type

• The open-loop gain of an op-amp is given at

225,000. Find the gain in dB.a. 1070

b.

107

c. 214d. 10.7

• A _____ is a solid material formed by atoms

bonding together in a fixed pattern.a. Block

b. Crystal

c. Latticed. Pyramid

• Elements with 5 or more valence electrons arecalled _____.

a. Semi-conductors b. Conductorsc. Molecule

d.

Insulators

• When the resistance of the load is high with respectto the resistance of the source _____ in a circuit is

achieved.a. Maximum power

b. High efficiency

c. Maximum transferd.

High voltage

• As the input voltage varies within specified limits,

the zener diode maintains a nearly constant outputvoltage across its terminal. This is called _____.

a. Auto regulation b. Specific regulation

c.

Line regulationd. Load regulation

• The method of assigning more sectors to the outer

disk tracks is referred to as _____ recording.a. Random

b. Zone

c.

Sector

d. System

• _____ is the unit of electrical current flow.

a. Volt b. Ohm

c. Amepered. Watte.

• According to Ohm’s Law, what happens to thecircuit current if the circuit resistance increases?

a. Current double

b.

Current decreases

c. Current increases

d. Current remains constant

• Determine the open loop gain of an Op-am whosecur-off frequency is 100 Hz with a midrange

voltage gain of 100,000.a. 7,071

b. 707.1

c. 70,710

d. 70.71

• DC biasing is used to establish a steady level of

transistor current. This is called the _____.a. Operating coordinates

b. Threshold pointc. Range of operation

d.

DC operating point

• Arc blow can be avoided in electrical welding by

_____a. Increasing arc length

b. Welding away from the earth groundconnection

c. Using bare electrodes

d.

Using AC welding machines

• The distance covered or traveled by a waveformduring the time interval of one complete cycle.

a. Frequency

b.

Wavelengthc. Time slot

d. Wave time

• _____ is the non-linear distortion characterized by

the appearance (at the system output)_ offrequencies equal to the sums or difference of twoor more frequencies at the input.

a. Differential distortion

b.

Inter modulation distortionc. Mutual distortiond. Modulated distortion



• Find the phase angle between the voltage across and

the current through the circuit when Xc is 25 ohms,R 100 ohms and Xl is 50 ohms.

a. 76 degrees with the voltage leading thecurrent

b. 14 degrees with the voltage lagging thecurrent

c.

14 degrees with the voltage leadingthe current

d. 76 degrees with the voltage lagging thecurrent

• If the resistance of a circuit is doubled and the

applied voltage is kept constant, the current will _____.

a. Be quadrupled

b. Remain the same

c.

Be cut in halfd. Be doubled

• To produce tin film resistors, which of thefollowing materials is the most widely used?

a. Titanium b. Tantalum

c.

Nichromed. Chromium cermets

• List the two advantages of a voltage divider in DC biasing

a. Unstable, uses two supply voltages b. Unstable, uses one supply voltage

c.

Stable, uses one supply voltages

d. Stable, uses two supply voltages

• _____ is a kind of oscilloscope which consist ofnarrowband if filter and a local oscillator (receiver)

capable of showing transmitter carriers, spacing,harmonics and sidebands.

a. Polygraph b. Harmonics analyzer

c.

Spectrum analyzerd. Computerized tomography

• One cycle is equal to how many degrees of rotation

of a conductor in a magnetic field?a. 270

b. 360

c. 180d. 90

• A measuring device which will result to full scale

reading at shorted terminal conditiona. Voltmeter

b. Ammeterc. Electrostatic meter

d.

Ohmmeter

• If the voltage gain for each input of a summing

amplifier with a 4.8 kilo-ohm feedback resistor isunity, the input resistors must have a value of _____kilo-ohm.

a. 4.8 times the number of inputs

b. 48c. 4.8 divided by the number of inputs

d.

4.8

• To match the waveguide to the load, _____ devices

are placed in the waveguide.a. Standing wave

b. Resistivec. Metal plate

d.

Impedance changing

• What is the generic term for utilities and programs

needed to operate a computer system?a. Hardware

b.

Software

c. People water

d. Tupper ware

• The computer worm that infected computer systems

world-wide in 10 minutes, making it the fastestcomputer virus ever known is called _____.

a. Claw Hammer b. Sledge Hammer

c.

SQL Hammerd. SARS Virus

• The channel of JFET is between the _____.

a. Input and output

b. Drain and sourcec. Gate and draind. Gate and source

• What is the common use of a push-pull amplifier?

a. AN OPAM

b. A driverc. Wideband amplifier

d. A coupler

• For a bipolar junction transition(eto tlga yung

nakalagay) (BJT) to operate properly, the base-collector junction should be _____ biased.

a.

Positive b. Forwardc. Negative

d. Reverse



• Large centralized data-processing complexes like

multi-national companies, departments andcorporations use which type of general-purposecomputer that operates programs simultaneously?

a. Mini-computer

b. Micro0computer

c. Main-frame computer

d. Super-computer

• In parallel resonant LC circuit, what is the

impedance at resonant frequency?a. Zero

b.

The maximum impedance value

c. Infinityd. Determined solely by the dc resistance

• The area in which the axis motion of a robotmanipulator can operate without any obstruction is

called the e_____.a. Work area

b. Range of operationc. Range of motion

d.

Work envelope

• The BEST choice electronic device to turn a device

at a particular voltage is a/an _____.a. SCR

b. SCS

c.

DIAC

d. PUT

• What term is used to describe the ability a system to

distinguish between targets that are close together?a. Radar sensitivity

b. Target designationc. Radar agility

d. target resolution

• What do you call a concept which describes the

relationship of all functional components of acomputer such as CPU and input./output devices?

a. Engineering development

b. Architecture

c. Prototypingd. Pre-production modeling

• The use of feedback to achieve the desired responseof a dynamic system in the presence of

uncertainties, disturbance or constraints is called _____.

a. Synchronization b. Response

c. Controld. Servomechanism

• The primary purpose of a voltage regulator is to

provide an output voltage with little or no _____.a. Figure of merit

b. Valuec. Regulation

d. Variation

• In waveguide theory, what causes the current-

carrying area at the center conductor of the coaxialline to be restricted to a small layer at the surface?

a. Dielectric losses b. Standing wave

c. Skin effectd. Copper losses

• This peak current specified for a given number of

cycles or portion of a cycle.a. Surge current

b. Maximum current

c. Peak surge current

d. High current

• An electron moves into the electrostatic field

between a positive charge and a negative charge.Toward which charge will the electron move?

a. Outwards b. The negative chargec. The center

d. The positive charge

• _____ is the definite discrete amount of energy

required to move an electron from a lower shell to ahigher shell

a.

Quantum

b. Positive energyc. The centerd. The positive charge

• Monolithic integrated circuits are usually referred toas _____.

a. Selenium rectifiers b. ?? (ndi ko na mabasa)

c.

Silicon chipsd. Hybrids

• _____ is an intermodulation condition that occurswhen a carrier modulates by an undesired signal.

a. Short modulation

b.

Cross modulation

c. Under modulationd. Over modulation



• In microwave tubes, what is the basic principle of

operations of a klystron?a. Strong electrostatic field

b. Energy transfer and amplificationc. Oscillation

d.

Velocity modulation

• An English scientist who drew up plans for the first

programmable computer in 1830a. Vannevar bush

b. William oughtred

c.

Charles Babbage

d. Herman hollerith

• In an optical coupler, this parameter is the ratio of

the output current to the input current through theLED, expressed in percentage. What is this ratio?

a.

DC current coupling ratio

b. AC current transfer ratioc. AC current coupling ratio

d. DC current transfer ratio

• _____ refers to the difference between the carrierfrequencies of an FM signal and the instantaneous

frequency of its modulated wave.a. Differential frequency

b.

Frequency deviation

c. Modulated frequencyd. Frequency band

• The most widely used abrasive is _____.

a. Tungsten b. Graphitec. Silicon carbide

d. Alumina

• The most common bias circuit providing Q-point

stability with a single polarity supply voltage iswhat type bias circuit

a. Collector feedback

b.

Voltage divider

c. Emitter

d. Base

• What happens to the portion of the wave front thatdo not satisfy the boundary conditions, when awavefront is radiated into a waveguide?

a. It collapses

b.

It decreases to zero

c. It is reflected backd. It increases to maximum

• The schokeydiode(eto tlga yungnakalagay. Schokey

diode) is a thyristor that conducts when the voltageacross its terminal exceed the _____ potential.

a. Trigger

b. Breakover

c. Operatingd. Maximum

• The value of the drain-to-source voltage of a GFETat which the drain current becomes constant when

the gate-to-source voltage is zero is called _____voltage.

a. Breakdown b. Cut offc. Threshold

d. Pinch off

• Insulators are characterized by a _____ energy gap between its conduction bands an valence band.

a. Very narrow

b. Widec. Very wided. Narrow

• _____ is an electrical current that flows in one

direction only.a. Normal current

b. Alternating current

c. Direct current

d. Eddy current

• The input resistance at the gate of an FET is _____.a. Relatively low

b. Zero

c.

Extremely highd. Average

• It is the generated in a D.C. motor as armature coilsout the field flux opposes the applied voltage, andlimits the flow of armature current.

a. Electromotive force b. Field excitation

c.

Counter-electromotive forced. Armature excitation

• The person responsible for the researend(as is)design and development of a complete informationsystem.

a.

PROGRAMMER

b. PEOPLE WAREc. SYSTEM ANALYSTd. COMPUTER OPERATOR



• In a robotic system, how many degrees of freedom

can be given to a manipulator by adding a wrist?a. Four

b. Six

c.

Three

d. Two

• Term for energy that is stored in electromagnetic orelectrostatic field.

a. Amperes-joules b. Joules-coulombs

c.

Potential energy

d. Kinetic energy

• What do you call the “Filter” between a corporate

network and the internet that keeps the corporatenetwork secure from intruders while givingcorporate users unhibited access to the internet?

a. Bandstep (as is) b. Bandpass

c. Firewalld. Firestorm

• Two basic categories of voltage regulators area. Differential, integral

b. Capacitive, inductive

c.

Linear switchingd. Centrifugal, centripetal

• A measure of the energy absorbed from radiation bytissue or other biological material and is a equal tothe transfer of 1 x 10-2 Joules energy per kilogram

of material is called a _____.a. Radical

b.

Radc. Radian

d. Radius

• The type of feedback used to increase amplitude ofoutput signal.

a. Negative feedback b. Unwanted feedback

c.

Positive feedback

d. Fidelity feedback

• A transistor constructed with three-doped

semiconductor region separated by two pn junctionis called a _____.

a. Metal oxide semiconductor FET

b. Field effect transistorc. Junction field effect transistor

d.

Bipolar junction transistor

• A type of filter that passes a narrow band of

frequencies though a current and attenuates thedesired band of frequencies that are high or lowerthan the desired band of frequencies.

a. Low-pass filter b. Band-reject filter

c.

Band-pass filterd. High-pass filter

• Which of the following are circuit control devices?

a. Switches b. Solenoidc. Relays

i. B and C only

ii. A and B only

iii.

A, B, and C

iv. A and C only

• What is an electric measuring equipment used innavigation which uses time measurement conceptfor a wave to travel from a place receiving station

and back?a. Tacan

b. OODRc. ILS

d. DME

• In a stand alone supply of power the rationale of

cells making in series is to _____.a. Increase current capacity

b.

Increase voltage outputc. Decrease voltage outputd. Decrease internal resistance

• _____ is the total number of magnetic lines of forcein a magnetic field.

a. Magnetic potential

b. Magnetic fluxc. Magnet flux intensityd. Flux density

• An electronic device that can be turned on and

turned off by a gate pulse is called a _____.a. Bipolar junction transistor

b.

Silicon-controlled switchc. Silicon-controlledrectirifer

d. Shockley diode

• A hot-carrier diode is a diode that ____.

a. Emits light when forward biased

b.

Switches very fastc. Varies resistance with temperature

d. Changes its capacitance with voltage

• An amplifier exhibits three critical frequencies in its

low-frequency response

a. None of these b. 167hertzc. 130 hertz

d.

75 hertz

• In a transformer, the principle of electromagneticinduction is also known as _____.

a. Coupling action

b. Transformationc. Matching action

d. Transformer action



• The symbols 1, 2 and 3 through 9 are what type of

numerals?a. Boolean

b. Romanc. Binary

d.

Arabic

• Type of semiconductor diode varies its internalcapacitance as the voltage applied to its terminalsvaries.

a. A zener diode

b.

A varactor diode

c. A silicon-controlled rectifierd. A tunnel diode

• What is the charge magnitude, Q of a body if itlacks 5 electrons?

A. 5 x 10-19 CoulombB. 5 CoulombC. 8 x 10-19 CoulombD. 19 x 10-19 Coulomb

ANSWER: C

• The net movement of charged particles in one

direction or another.A. flowB. currentC. drift current

D. diffusion currentANSWER: B

• The rate at which electrons pass a given point in

the circuit gives the magnitude ofA. electron current

B. magnetic currentC. drift currentD. diffusion current

ANSWER: A

• The unit of current.A. Ampere

B. Ampere/sec.C. Ampere-sec.D. Ampere-hr.

ANSWER: A

• The unit Ampere is equivalent toA. one Coulomb/second

B. one Coulomb/minC. one Joule/sec

D. one Joule/minANSWER: A

• When one coulomb of electric charge

continuously passes a given point every second,the electric current is said to

A. 1 µAB. 1 mAC. 1 A

D. 10 AANSWER: C

• One ampere is equal to how many electrons per

second?A. 1 x 1018 electrons/sec.B. 1 x 1019 electrons/sec.C. 6.25 x 1018 electrons/sec.

D. 6.25 x 1019 electrons/sec.ANSWER: D

• The bigger the diameter of a wire,

A. more current can passB. less current can passC. more heat is generated when current

flowD. the higher is the electrical resistance

ANSWER: A

• If in a material, current can hardly pass, it meansA. the material is very hard

B. the material is very softC. the material has high resistanceD. the material has less resistance

ANSWER: C

• The greater the diameter of a wire, the _______ is

the resistance.A. greater

B. lesserC. harderD. bigger

ANSWER: B

• The longer the wire the ________ is the

resistanceA. higherB. lesserC. harder

D. smallerANSWER: A

• If a conductor’s cross-sectional area is doubled

and its length is halved, the value of its resistancewill

A. double

B. quadrupleC. decrease by a factor of twoD. decrease by a factor of four

ANSWER: D

• The amount of resistance that a wire has with

regards to the flow of electric currentA. is less for a conductor than for an

insulatorB. is less for an insulator than for a

semiconductorC. is less for a semiconductor than for a

conductorD. is high for a semiconductor than for an

insulatorANSWER: A



• The area of a conductor whose diameter is 0.001

inch is equal toA. one angstromB. one circular milC. one micron

D. one steradianANSWER: B

• A 100m long wire with a cross-sectional area

A=10-3 m2 has a resistance of 10Ω. Determine theresistivity of the wire.

A. 10-2 Ω-m

B. 10-3 Ω-mC. 10-4 Ω-mD. 10-5 Ω-m

ANSWER: C

• the reciprocal of resistance

A. permeanceB. elastanceC. inductanceD. conductance

ANSWER: D

• The science of physical phenomena at very low

temperature, approaching absolute zero is called ________.

A. crytanalysis

B. cyberneticsC. temperature inversion

D. cryogenicsANSWER: D

• What happens in the resistance of copper wirewhen its temperature is raised?

A. decreased

B. steadyC. increasedD. zero

ANSWER: C

• A wire has a resistance of 5Ω at roomtemperature and a temperature coefficient

α=4x10-3/°C, calculate the wire resistance at75°C.

A. 8.925 Ω B. 7.925 Ω

C. 6.925 Ω D. 6.050 Ω

ANSWER: D

• The temperature coefficient of resistance of acertain wire is known to be 0.004/°C at zero

degrees Celsius. What would be thetemperature coefficient at room temperature?

A. 0.00018/°CB. 0.00036/°C

C. 0.00180/°CD. 0.00360/°C

ANSWER: D

• Where does practically all of the RF current flow

in a conductor?A. along the surfaceB. in the center of the conductorC. in the electromagnetic field in the

conductor centerD. in the magnetic field around the

conductorANSWER: A

• ________ is one factor that does not affectresistance.

A. Cross sectional areaB. ResistivityC. MassD. Length

ANSWER: C

• Why is the resistance of a conductor different for

RF current than for DC?A. Because of skin effectB. Because conductors are non-linear

devicesC. Because the insulation conducts current

at radio frequencyD. Because of the Heisenberg effect

ANSWER: A

• The ability of a material to resist current flowis called “resistance”. What is (are) the

factor(s) that affect its value?A. temperatureB. length & cross-sectional area

C. atomic structureD. all of these

ANSWER: D

• Find the charge in coulombs of dielectric thathas a positive charge of 14.5 x 10 to the 18 th

power protons.A. 29 x 10 to the 16th CoulombsB. 14.5 x 10 to the 16th CoulombsC. 14.5 x 10 to the 18th Coulombs

D. 29 x 10 to the 18th CoulombsANSWER: C

• Electron volt (eV) is a unit of

A. powerB. energyC. magnetic field

D. magnetic forceANSWER: B

• One electron volt (eV) is equivalent to

A. 1.0 watt-secB. 1.6 x 10-19 watt-sec

C. 1.0 JouleD. 1.6 x 10-19 Joules

ANSWER: D



• What law that describes the force of attraction

or repulsion between two charges is directly proportional to their strengths and inversely proportional to the square of the distance between them?

A. Coulomb’s first lawB. Coulomb’s second law

C. Coulomb’s third lawD. Coulomb’s law or law of electrostatics

ANSWER: D

• What is the law whereby the force of attraction

and repulsion between poles is inversely proportional to the square of the distance between them?

A. Newton’s first lawB. Newton’s second law

C. Norton’s lawD. Coulomb’s second law

ANSWER: D

• Is usually used to detect the presence of electric

charge.A. experimental chargeB. unit chargeC. dipoleD. test charge

ANSWER: D

• Test charge has a charge of

A. 0 CoulombB. +1 CoulombC. -1 Coulomb

D. InfinityANSWER: B

• Three charges of +5 C, -6 C and +7 C are placed inside a sphere, what is the total charge

of the sphere?A. +5 Coulomb

B. -6 CoulombC. -7 CoulombD. +6 Coulomb

ANSWER: D

• A combination of two charges, with equal charge

magnitude but opposite signs.A. magnetic dipoleB. static dipoleC. dynamic dipole

D. electric dipoleASNWER: D

• The space outside or surrounding an electric

charge where it has a force of attraction orrepulsion.

A. Electric fieldB. Magnetic fieldC. Electromagnetic fieldD. Electric flux

ANSWER: A

• Refers to a force of field that exists between

ions where they either repel or attract eachother.

A. Resisting field

B. Potential field

C. DielectricD. Electromotive

ANSWER: D

• The imaginary lines representing the electricfield.

A. Electric field

B. Electric fluxC. Electric flux densityD. Electric lines of force

ANSWER: D

• What is true in visualizing electric field lines of

force from a charge body?A. Field lines are continuous curve and

they never intersect.B. The spacing between these lines

increases as they get far from thecharged body.

C. The number of field lines is directly proportional to the magnitude of theelectric field.

D. All of the above.ANSWER: D

• What do you call the total number of electriclines of force in an electric field?

A. Electric fieldB. Electric flux

C. Electric flux densityD. Electric lines of force

ANSWER: B

• The number of lines per unit area in a plane perpendicular to the electric lines of force.

A. Electric fieldB. Electric fluxC. Electric flux densityD. Electric lines of force

ANSWER: C

• Electric lines of force leave and enter the charge

surface at what angle?A. 15°B. 30°C. 45°

D. 90°ANSWER: D

• Find the dielectric constant of air.

A. approximately 1B. approximately 0

C. approximately 2D. approximately 4

ANSWER: A



• Electric field intensity is measured in terms of

A. Volts/meterB. Newtons/meterC. Watts/meterD. Amperes/meter

ANSWER: A

• Electric field intensity isA. a scalar quantityB. a vector quantityC. an absolute valueD. a relative value

ANSWER: B

• Electric flux is a/an ________ quantity.

A. scalarB. vectorC. absolute

D. relativeANSWER: A

• Electric flux density is a/an ________ quantity.

A. scalarB. vector

C. absoluteD. relative

ANSWER: B

• Three charges of +5 C, -6 C, and +7 C areinside a sphere, what is the total electric flux

passing through the surface of the sphere?

A. 5 CoulombsB. 6 CoulombsC. 7 CoulombsD. 8 Coulombs

ANSWER: B

• An electric charge produces a total electric

field of 6 Coulombs, calculate the electric fluxdensity in an area of one square meter (1m2).

A. 1 C/m2 B. 2 C/m2

C. 4 C/m2 D. 6 C/m2

ANSWER: D

• The measure of density of the electric chargeA. Electric gradient

B. Electric currentC. Electric charge

D. Electric potentialANSWER: D

• The ability of the material to store electrical potential energy under the influence of an

electric field.A. capacityB. permeabilityC. permittivity

D. conductivityANSWER: C

• The absolute permittivity of air or free space.

A. 1/36π x 10-9 F/mB. 36π x 10-9 F/mC. 1/36π x 10-19 F/mD. 36π x 10-19 F/m

ANSWER: A

• The relative permittivity of air.A. 0B. 1C. 1/36π x 10-9 F/mD. 8.854 x 10-12 F/m

ANSWER: B

• Calculate the permittivity of a material with

relative permittivity of 5.A. 8.854 x 10-11 F/mB. 4.42 x 10-11 F/m

C. 1/36π x 10-9 F/mD. 8.854 x 10-12 F/m

ANSWER: B

• What is the term used to express the amount of

electrical energy stored in an electrostaticfield?

A. Volts

B. WattsC. CoulombsD. Joules

ANSWER: D

• How does permittivity affect electric field

intensity?A. It causes the field intensity to increase.B. It causes the field intensity to decrease.C. It causes the field intensity to fluctuate

up and down.D. It has no effect on field intensity.

ANSWER: B

• Relative permittivity is also known asA. dielectric constantB. dielectric strength

C. isolation strengthD. permeability

ANSWER: A

• Most materials’ relative permittivity lies betweenA. 0.01 – 1B. 1 – 10

C. 10 – 50D. 50 – 100

ANSWER: B



• Charge body at rest is said to exhibit electric

field, which interacts with other bodies. Thestudy of this phenomena is known as

A. electricityB. electrostatics

C. electromagnetismD. field interactions

ANSWER: B

• The basic law for interaction of charged bodies atrest.

A. Charged law

B. Gauss’ lawC. Faraday’s law

D. Coulomb’s lawANSWER: D

• The force between the two electrically charged

body is calledA. electromotive forceB. electrostatic forceC. electromagnetic force

D. magnetic forceANSWER: B

• The force between two electrically charged body

isA. directly proportional to the chargeB. inversely proportional to the charge

C. not affected by the chargeD. universally constant

ANSWER: A

• In 1784, who demonstrated that the force between charges is inversely related to thesquare of the distance between them?

A. MaxwellB. Gauss

C. TeslaD. Coulomb

ANSWER: D

• Determine the force in Newton between 4μCcharges separated by 0.1 meter in air.

A. 1.44 NB. 14.4 NC. 144 N

D. 1440 NANSWER: B

• What will happen when two opposite charges

get closer?A. repels less

B. attracts lessC. repels moreD. attracts more

ANSWER: D

• The value of k in Coulomb’s electrostatic force

equation ( F = kQ1Q2/r 2 ) is oftentimes

expressed as 1/4πεο. What is εο?A. absolute permeabilityB. absolute permittivity

C. relative permeabilityD. relative permittivity

ANSWER: B

• The measure of electric field strength per unitlength is known as electric field intensity orsimply electric intensity. What is its unit?

A. Volt/meter (V/m)B. Joules/Coulomb-meter (J/Cm)

C. Newton/Coulomb (N/C)D. All of the above

ANSWER: D

• Calculate the electric field intensity 10cm from

a charge Q=5nC.A. 450 N/CB. 900 N/C

C. 4.5 x 103 N/CD. 9.0 x 103 N/C

ANSWER: C

• Determine the magnitude of the electric fieldinside a sphere that encloses a net charge of

2μC.

A. 0 (zero)B. 9 x 107 N/CC. 1.8 x 108 N/C

D. infiniteANSWER: A

• Calculate the total electric field at the surface

of a sphere of radius r=1cm, and enclosing a

net charge of 2μC. A. 0 (zero)

B. 9 x 107 N/CC. 1.8 x 108 N/CD. infinite

ANSWER: C

• A 2nC point charge will produce what potential at 2m away?

A. 4.0 VoltsB. 6.0 VoltsC. 7.5 VoltsD. 9.0 Volts

ANSWER: D

• A charged body in free space produces 10-V

potential at a distance 25cn away. What will bethe potential at 50cm away?

A. 5.0 Volts

B. 7.5 VoltsC. 10.0 VoltsD. 15.0 Volts

ANSWER: A



• What do you call the phenomenon whereby

substance attracts pieces of iron?A. PermeabilityB. MagnetismC. Naturalism

D. ElectromagnetismANSWER: B

• The condition in which a substance attracts

pieces of iron is known asA. ElectromagnetismB. Electrolysis

C. MagnetismD. Magnetic Induction

ANSWER: C

• A substance that attracts pieces iron is knownas

A. magnetB. conductorC. ferriteD. superconductor

ANSWER: A

• A natural magnet

A. loadstoneB. carbonC. lodestoneD. magnesium

ANSWER: C

• Group of magnetically aligned atoms.

A. LatticeB. CrystalC. DomainD. Range

ANSWER: C

• In a magnet, what do you call the point in

which the magnetic lines of force ismaximum?

A. maximum poleB. intensified pole

C. unit poleD. magnetic pole

ANSWER: D

• Which of the following refers to acharacteristic of a magnetic line of force?

A. Travels from south to north through thesurrounding medium of a bar magnet

B. Travels back and forth between thenorth and south pole of a bar magnet

C. Travels from north to south through thesurrounding medium of a bar magnet

D. Stay stationary between the north andthe south of a bar magnet

ANSWER: C

• Is believed to be the pole where the magnetic

lines of force are originating.A. North PoleB. South Pole

C. Unit Pole

D. Universal PoleANSWER: A

• What do you call a pole that when place in air

with a similar and equal pole will cause a force

of repulsion of 1/4πμο Newtons?A. South Pole

B. Unit poleC. Convergence poleD. Universal Pole

ANSWER: B

• In a magnet, the straight line passing through

the two poles is calledA. real axisB. imaginary axisC. Cartesian axis

D. magnetic axisANSWER: D

• The phenomenon in which a substance

becomes a magnet when placed near a magnet.A. magnetic transfer

B. magnetic inductionC. electromagnetism

D. magnetismANSWER: B

• A force which causes a substance to become amagnet.

A. magnetizing forceB. magnetomotiveC. creative forceD. electromagnetic force

ANSWER: A

• What do you call the quantity of magnetism

retained by a magnetic material after thewithdrawal of a magnetizing force?

A. Left over magnetismB. Coercivity

C. HysteresisD. Residual magnetism

ANSWER: D

• Is the property of magnetic materials, whichretain magnetism after the withdrawal of

magnetizing force.A. retentivity

B. permeabilityC. reluctivity

D. susceptabilityANSWER: A



• A substance having high retentivity is best

suited in makingA. an electromagnetB. a temporary magnetC. a permanent magnet

D. two pole magnetANSWER: C

• Which of the materials below that can be easily

magnetized?A. soft magnetic materialsB. hard magnetic materials

C. low conductive materialsD. high conductive materials

ANSWER: A

• Materials that can be easily magnetized in bothdirections

A. soft magnetic materialsB. hard magnetic materialsC. diamagneticD. paramagnetic

ANSWER: A

• Ability of a material to conduct magnetic flux

through it refers toA. permittivityB. permeabilityC. reluctivity

D. conductivityANSWER: B

• The ability to concentrate magnetic lines of

force.A. retentivityB. permeability

C. susceptabilityD. reluctivity

ANSWER: B

• The permeability of free space.A. 4π x 10-7 H/mB. 12.56 x 10-7 F/m

C. 8.854 x 10-7 H/mD. 8.854 x 10-12 F/m

ANSWER: A

• The ratio of material permeability to the permeability of air or vacuum.

A. relative conductivityB. relative permeability

C. inverse permeabilityD. inverse permittivity

ANSWER: B

• What is the relative permeability of air?

A. 0B. 1C. 4π x 10-7 H/mD. 8.854 x 10-12 F/m

ANSWER: B

• Materials with permeability slightly less than

that of free space.A. diamagneticB. paramagneticC. ferromagnetic

D. antimagneticANSWER: A

• Materials with permeability slightly greater

than that of free space.A. diamagneticB. paramagnetic

C. ferromagneticD. antimagnetic

ANSWER: B

• What do you call materials, which possess veryhigh permeabilities?

A. diamagneticB. paramagneticC. ferromagneticD. antimagnetic

ANSWER: C

• What is the relative permeability of

paramagnetic substance?

A. slightly greater than 1B. very much greater than 1C. slightly less than 1

D. very much smaller than 1ANSWER: A

• Permeability of a material means:

A. The ability of the material to conductelectric field

B. The conductivity of the material for

electromagnetic fieldC. The ability of the material to hold

magnetic fluxD. The conductivity of the material for

magnetic lines of forceANSWER: D

• Nonmetallic materials that has ferromagnetic

properties.A. termitesB. ferrites

C. ferrousD. loadstone

ANSWER: B

• Cores of magnetic equipment use magneticmaterial which has

A. very low permeabilityB. moderate permeabilityC. low permeabilityD. high permeability

ANSWER: D



• Hydrogen is an example of a _________

material.A. diamagneticB. ferromagneticC. paramagnetic

D. magneticANSWER: A

• Cobalt is an example of a _________ material.

A. diamagneticB. ferromagneticC. paramagnetic

D. magneticANSWER: B

• The space outside a magnet where its poles has

a force of attraction or repulsion on anothermagnetic pole.

A. magnetic fieldB. magnetic fluxC. magnetic flux densityD. magnetic lines of force

ANSWER: A

• The imaginary lines representing the magneticfield.

A. magnetic fieldB. magnetic fluxC. magnetic flux density

D. magnetic lines of forceANSWER: D

• What do you call the total number of magnetic

lines of force in a magnetic field?A. magnetic fieldB. magnetic flux

C. magnetic flux densityD. magnetic lines of force

ANSWER: B

• The number of lines per unit area in a plane perpendicular to the magnetic lines of force.

A. magnetic field

B. magnetic fluxC. magnetic flux densityD. magnetic lines of force

ANSWER: C

• The direction of field lines outside a magnet isA. from north to south pole

B. from south to north pole

C. either from north to south or south tonorth pole

D. dependent on the magnet’s orientationwith respect to the earth’s magnetic

poleANSWER: C

• The entire group of magnetic field lines

flowing outward from the north pole of amagnet.

A. magnetic fieldB. magnetic flux density

C. magnetic flux

D. electromagnetic field

ANSWER: C

• Magnetic lines of force are calledA. magnetic fieldB. magnetic flux density

C. magnetic fluxD. electromagnetic field

ANSWER: C

• What is the unit of magnetic flux in SI system?

A. WeberB. Maxwell

C. TeslaD. Gauss

ANSWER: A

• The unit of magnetic flux density in SI:

A. GaussB. WeberC. Maxwell

D. TeslaANSWER: D

• A magnetic flux of 25,000 maxwell in an area

of 5 sqcm. results in flux density ofA. 5,000 Gauss (G)B. 125,000 G

C. 5,000 Tesla (T)D. 125,000 T

ANSWER: A

• Calculate the flux density in Gauss (G) havinga flux of 12,000 Mx through a perpendiculararea of 6cm.

A. 200 GB. 2,000 GC. 7,200 GD. 72,000 G

ANSWER: B

• What does a gaussmeter measure?

A. fluxB. magnetic fieldC. magnetic flux density

D. mmfANSWER: C

• The capacity of a substance to become

magnetized. This is expressed as a ratio between the magnetization produced in asubstance to the magnetizing force producing

it.A. magnetic conductivityB. magnetic susceptibilityC. magnetic resistivity

D. magnetic reluctivityANSWER: B



• The typical saturation flux density for most

magnetic materials.A. 0.1 Wb/m2 B. 2 Wb/m2 C. 10 Wb/m2

D. 20 Wb/m2 ANSWER: B

• The force between two magnetic poles is

_________ permeability of the medium.A. directly proportional to theB. inversely proportional to the

C. not dependent of theD. exponentially proportional to the

ANSWER: B

• If the distance between two magnetic poles ishalve, the force between them

A. decreases two timesB. decreases four timesC. increases two timesD. increases four times

ANSWER: D

• A force of 20 N is acting on a 10 Wb magnetic pole, calculate the intensity of the magnetic

field?A. 0.5 N/WbB. 2 N/Wb

C. 10 N/WbD. 20 N/Wb

ANSWER: B

• Unit of permeabilityA. Henry/meter (H/m)B. Farad/meter (F/m)

C. Henry-meter (H-m)D. Farad-meter (F-m)

ANSWER: A

• The unit of permittivityA. Henry/meter (H/m)B. Farad/meter (F/m)

C. Henry-meter (H-m)D. Farad-meter (F-m)

ANSWER: B

• Magnetic intensity isA. a vector quantity

B. a scalar quantityC. an imaginary quantity

D. either a vector or scalarANSWER: A

• The Gauss is a unit ofA. permeability

B. electromagnetic forceC. magnetic forceD. magnetic flux density

ANSWER: D

• What is the unit of flux in cgs?

A. Ampere-turn (At)B. Coulomb/sec. (C/s)

C. Maxwell (Mx)D. Gauss

ANSWER: C

• One Weber is equivalent toA. 108 MaxwellsB. 106 MaxwellsC. 104 MaxwellsD. 102 Maxwells

ANSWER: A

• The equivalent of 1 x 109 Maxwells is

A. 1 WeberB. 10 WeberC. 100 Weber

D. 1,000 WeberANSWER: B

• A magnetic flux of 500,000,000 lines is

equivalent toA. 5 x 108 MaxwellsB. 5 Weber

C. 500 x 106 MAxwellsD. all of the above

ANSWER: D

• The unit of flux density in mksA. GaussB. Weber/m2

C. MaxwellD. Tesla

ANSWER: B

• What do you call the force that sets up or tendsto set up magnetic flux in a magnetic circuit?

A. electromotive forceB. potential difference

C. magnetomotive forceD. dynamic force

ANSWER: C

• Voltage in electrical circuits is analogous to

_________ in magnetic circuits.A. Ampere-turnB. Magnetomotive forceC. Magnetizing force

D. FluxANSWER: B

• Electrical current is analogous to _________ in

magnetic circuits.A. Ampere-turnB. Magnetomotive force

C. Magnetizing forceD. Flux

ANSWER: D



• __________ capability is analogous to

permeance.A. AdmittanceB. ConductanceC. Reluctance

D. ResistanceANSWER: B

• Resistance in electrical circuits is analogous to

_________ in magnetic circuits.A. ConductanceB. Permeance

C. ElastanceD. reluctance

ANSWER: D

• The property of a material which opposes thecreation of magnetic flux.

A. elastanceB. permeanceC. susceptanceD. reluctance

ANSWER: D

• The reciprocal of reluctance

A. conductanceB. permeanceC. elastanceD. capacitance

ANSWER: B

• Permeance is analogous to

A. conductanceB. resistanceC. impedanceD. elastance

ANSWER: A

• Is the reciprocal of reluctance and implies the

readiness of a material to develop magneticflux.

A. elastanceB. permeance

C. susceptanceD. conductance

ANSWER: B

• Magnetic circuit property that permits flux.A. elastance

B. permeanceC. susceptance

D. conductanceANSWER: B

• It is easier to establish flux line in soft ironthan it is to establish them in air, this is

because iron has a lowerA. PermeanceB. InductanceC. elastance

D. reluctanceANSWER: D

• The Oersted (Oe) is the same as

A. 1 Gb/cmB. 1 Gb/mC. 10 Gb/cm

D. 10 Gb/cm

ANSWER: A

• The unit of reluctanceA. GilbertB. TeslaC. At/WbD. Gauss

ANSWER: C

• It is the specific reluctance of a material.A. resistivityB. retentivityC. reluctivity

D. permeabilityANSWER: C

• At/m is a unit of

A. magnetic field

B. reluctanceC. magnetizing forceD. magnetic power

ANSWER: C

• Magnetomotive force has a unit of

A. Volt (V)B. Watt (W)C. Joule (J)D. Ampere-turn (At)

ANSWER: D

• The cgs unit of magnetomotive force

A. Volt

B.

WeberC. GilbertD. Ampere-turn

ANSWER: C

• One Gilbert is equal to

A. 0.0796 AtB. 0.796 AtC. 7.96 At

D. 79.6 AtANSWER: B

• One Ampere-turn (At) is equivalent to

A. 0.126 GilbertB. 1.260 Gilberts

C. 12.60 GilbertsD. 126 Gilberts

ANSWER: B

• The current needed for a coil of 200 turns to

provide a 400 ampere turn magnetizing force isA. 2 A

B. 4 AC. 6 AD. 8 A

ANSWER: A



• Determine the ampere-turns when a 10 V

battery is connected across a solenoid having

100 turns and a resistance of 5 Ω. A. 50 At

B. 200 AtC. 100 At

D. 1,000 AtANSWER: B

• What is residual magnetism?A. The external magnetic field when the

current is flowing through the excitingcoil.

B. The flux density, which exist in the ironcore when the magnetic field intensity

is reduced to zero.

C. The flux density, which exist in the ironcore when the magnetic field intensityis at its maximum value.

D. The flux density when the magneticcore is saturated.

ANSWER: B

• When you demagnetize property by applyingan AC field and then gradually reduced it tozero, it is called

A. dampingB. decayingC. degaussingD. gaussing

ANSWER: C

• In a magnetic circuit, a flux that drifts away

from its intended path is calledA. lost fluxB. linked flux

C. drift fluxD. leakage flux

ANSWER: D

• Is the quantity of magnetizing force needed to

counter balance the residual magnetism of amagnetic material.

A. hysteresisB. degaussingC. retentivityD. coercivity

ANSWER: D

• What do you call the loss of electrical energy

in counter balancing the residual magnetism ineach cycle?

A. hysteresisB. magnetomotive

C. leakageD. coercivity

ANSWER: D

• The amount of magnetic field needed to

remove residual magnetism from a transformercore during each half cycle is called the

A. coercive force

B. residual fieldC. hysteresis field

D. demagnetizing force

ANSWER: A

• If a wire coil has 100 turns and carries 1.3 A ofcurrent, calculate the magnetomotive force inGilbert.

A. 163.3B. 16.33C. 1.633D. 0.1633

ANSWER: A

• An advantage of an electromagnet over a

permanent magnetA. An electromagnet can be demagnetizedB. An electromagnet is simpler

C. An electromagnet is cheaperD. An electromagnet can be switched ON

and OFFANSWER: D

• Electromagnet whose core is in the form of aclose magnetic ring

A. solenoidB. relayC. toroidD. circular

ANSWER: C

• Magnetic flux can always be attributed to

A. static charged particlesB. motion of charge particlesC. static electric fieldD. every applied potential

ANSWER: B

• What is a magnetic field?A. A force set up when current flows

through a conductor.B. A force set up when a charged body is

at static.

C. The space between two electricallycharged particles.

D. The space around a conductor.ANSWER: A

• Which of the following determines the strength

of a magnetic field around a conductor?A. amount of currentB. diameter of the conductorC. length of the conductor

D. amount of voltageANSWER: A



• The magnetic flux around a straight, current

carrying wire, is strongerA. near the edgeB. near the wireC. at the center

D. at both edgeANSWER: B

• In what direction is the magnetic field about a

conductor when current is flowing?A. In a direction determined by the left-

hand rule.

B. Always in a clock wise direction.C. Always in a counter clockwise

direction.

D. In a direction determined by the right-hand screw rule.

ANSWER: A

• If the electrical current carried by each of the

two long parallel wire is doubled, and theirseparation is also doubled, the force between

themA. also doublesB. increases by a factor of fourC. decreases by a factor of fourD. decreases by a factor of two

ANSWER: A

• Reversing the flow of current in a circuit

A. reverses the magnetic polarityB. increase the magnetic field intensityC. decreases the magnetic intensity

D. enhances hysteresisANSWER: A

• Is used to maintain strength of magnetic field.

A. storerB. energizerC. gausser

D. keeperANSWER: D

• What law that describes the force of attraction

or repulsion between two magnetic poles isdirectly proportional to their strengths?

A. Coulomb’s first law

B. Coulomb’s second lawC. Ampere’s lawD. Gauss’ law

ANSWER: A

• What is the law whereby the force of attraction

or repulsion between poles is inversely proportional to the square of the distance between them?

A. Coulomb’s first law

B. Coulomb’s second lawC. Coulomb’s third lawD. Coulomb’s law

ANSWER: B

• The physical motion resulting from the forces

of magnetic fields.A. motor actionB. linear motionC. rectilinear motion

D. generator action

ANSWER: A

• What law in electronics where an induced

current will be in such a direction that its ownmagnetic field will oppose the magnetic fieldthat produces the same?

A. Electromagnetic lawB. Nortons lawC. Lenz lawD. Maxwell law

ANSWER: C

• A changing magnetic field

A. produces an electric fieldB. induces potentialC. produces a fluctuating electric field

D. produces a steady electric fieldANSWER: B

• The emf induced in a coil due to the change of

its flux linked with it is calledA. mutual emfB. crossfire induced emf

C. self induced emfD. virtually induced emf

ANSWER: C

• If two coils are close enough together for theirmagnetic fields to interact, a change in currentin one will induce a corresponding voltage in

the other, This condition is known asA. self-inductanceB. mutual inductanceC. crossfire inductance

D. linked inductanceANSWER: B

• If the magnetic flux through a coil changes, the

induced EMF acts in such a direction as toA. oppose that changeB. magnify that change

C. augment that changeD. amplify that change

ANSWER: A

• When a conductor is moved through amagnetic field a voltage is always induced.

The amount of voltage is always proportionalto

A. the diameter of the conductor usedB. the length of the conductor

C. the distance of the conductor from thefield

D. the rate at which the conductor ismoved

ANSWER: D



• The term of energy that is stored in an

electromagnetic or electrostatic fieldA. kinetic energyB. static energy

C. dynamic energyD. potential energy

ANSWER: D• What is meant by back EMF?

A. A voltage that is applied in the reversedirection.

B. An EMF that is dude to the fly wheel

effect.C. An EMF that is generated from the

back of an electromagnet.D. A voltage that opposes the applied

EMF.

ANSWER: D

• When current in a conductor increases, Lenz’

law states that the self-induced potential willA. produce current opposite to the

increasing currentB. tend to produce more magnetic fieldC. tend to augment the increase in currentD. produce current with the same direction

to the increasing current

ANSWER: A

• If a magnetic flux occurs across 100 turns at a

rate of 2 Wb/sec. What is the induced voltageas per Faraday’s law?

A. 100 V

B. 400 VC. 200 VD. 800 V

ANSWER: C

• The circuit element that is used represent theenergy stored in a magnetic field.

A. resistanceB. capacitanceC. inductance

D. elastance

ANSWER: C

• Which of the given below can produce themost induced voltage?

A. 1 A dcB. 1 A, 60 HzC. 50 A dcD. 1 A, 400 Hz

ANSWER: D

• In all cases of electromagnetic induction, the

current set-up by an induced voltage tends tocreate flux whose direction opposes anychange in the existing flux. This law is called

A. Ampere’s lawB. Lenz’ lawC. Coulomb’s lawD. Faraday’s law

ANSWER: B

• In electromagnetism, what law that determines

the polarity of an induced voltage?A. Ampere’s lawB. Lenz’ law

C. Coulomb’s lawD. Faraday’s law

ANSWER: B• In electromagnetism, what law that determines

the amount of induced voltage?A. Ampere’s lawB. Lenz’ law

C. Coulomb’s lawD. Faraday’s law

ANSWER: D

• Electromotive force (emf) is induced whenevera conductor cuts magnetic flux

A. Faraday’s first lawB. Faraday’s second lawC. Coulomb’s first lawD. Coulomb’s second law

ANSWER: A

• The magnitude of electromotive force (emf)

that is induced when a conductor cuts magneticflux is directly proportional to its rate.

A. Faraday’s first lawB. Faraday’s second law

C. Coulomb’s first lawD. Coulomb’s second law

ANSWER: B

• The effect that describes the ability of amechanically stressed ferromagnetic wire torecognize rapid switching of magnetization

when subjected to a DC magnetic field.A. Wiegand effectB. Wertheim effectC. Wiedemann effect

D. Wall effectANSWER: A

• The concept whereby a small voltage is

generated by a conductor with current in anexternal magnetic field is known as

A. Wiegand effect

B. Hall effectC. Wiedemann effectD. Wall effect

ANSWER: B

• _________ is called the magnetic field.

A. The force that drives current through aresistor

B. Current flow through space around a

permanent magnet

C. The force between the plates of chargedcapacitor

D. A force set up when current flowthrough a conductor

ANSWER: D



• The natural magnet refers to

A. steelB. soft ironC. magnesiaD. loadstone (lodestone)

ANSWER: D

• The force between two magnetic poles inrelation to their pole strength is ________.

A. not relatedB. inversely proportionalC. directly proportional

D. independentANSWER: C

• What do you call an amplifier which has an

output current flowing during the whole inputcurrent cycle?

A. class AB amplifier

B. class B amplifier

C. class A amplifier

D. class C amplifier

ANSWER: C

• Class A amplifier can be built from whattransistor configuration?

A. common base

B. common emitter

C. common collector

D. all of the aboveANSWER: D

• If a transistor amplifier provides a 360° outputsignal, it is classified as

A. class A

B. class B

C. class C

D. class DANSWER: A

• An amplifier that delivers an output signal of

180° only.

A. class A

B. class B

C. class AB

D. class D

ANSWER: B

• A class of amplifiers wherein the output signal

swings more than 180° but less than 360°. A. class A

B. class B

C. class C

D. class ABANSWER: D

• What is the distinguishing feature of a class C

amplifier?

A. Output is present for less than 180degrees of the input signal cycle

B. Output is present for the entire signal

cycle

C. Output is present for exactly 180

degrees of the input signal cycle

D. Output is present for more than 180degrees but less than 60 degrees of the

input signal cycleANSWER: A

• A full 360° sine-wave signal is applied as an

input to an unknown class of amplifier, if theoutput delivers only a pulse of less than 180°, of

what class does this amplifier belongs?

A. class AB

B. class B

C. class C

D.class DANSWER: C

• Which class of amplifiers that is intended for

pulse operation?

A. class B

B. class C

C. class D

D. class SANSWER: C

• How do you classify an amplifier used to amplify

either amplitude modulated (AM) or frequencymodulated (FM) signals?

A. class CB. class BC

C. class D

D. class SANSWER: D

• Which class of amplifiers that has the highestefficiency?

A. class A

B. class B

C. class C

D. class DANSWER: D

• What is the efficiency of a series-fed class Aamplifier?

A. 25%

B. 50%

C. 78.5%

D. above 90%

ANSWER: A



• A class A amplifier has an efficiency of only

25%, but this can be increased if the output iscoupled with a transformer. Up to how much isits efficiency will reach due to coupling?

A. 36.5%

B. 50%

C. 68.5%

D. 78.5%ANSWER: B

• Class B amplifiers deliver an output signal of180° and have a maximum efficiency of

A. 50%

B. 68.5%

C. 78.55

D. above 90%ANSWER: C

• Transistorized class C power amplifiers willusually have an efficiency of

A. 25%B. 33%

C. 50%

D. 78.5%

ANSWER: B

• For pulse-amplification, class D amplifier is

mostly used. How efficient is a class D amplifier?

A. about 25% efficient

B. less efficient than class B

C. more efficient than class A but lessefficient than class B

D. its efficiency reaches over 90%ANSWER: D

• An amplifier of class AB means its output signal

is between the output of class B and A, such thatit varies from 180° (class B) to 360° (class A).

How about its efficiency?

A. Efficiency of class AB is in betweenthe efficiency of class A and B, that isfrom 25% - 78.5%.

B. It is always as efficient as class A

(25%).

C. It is always as efficient as class B(78.5%)

D. The efficiency of class AB is the

average of the efficiencies of both classA and class B (25% + 78.5%)/2 =51.75%

ANSWER: A

• Among the given amplifiers below, which is the

most efficient?

A. class A (series-fed)

B. class A (transformer-coupled)

C. class A (directly-coupled)

D. class A (capacitor-coupled)

ANSWER: B

• In order to have the best efficiency and stability,

where at the loadline should a solid state poweramplifier be operated?

A. Just below the saturation point

B. At 1.414 times the saturation point

C. Just above the saturation point

D. At the saturation point

ANSWER: A

• In most transistor class A amplifiers, thequiescent point is set at

A. near saturation

B. near cutoffC. below cutoff

D. at the centerANSWER: D

• For a class B amplifier, the operating point or Q- point is set at

A. the top of the load line

B. saturation

C. the center

D. cutoffANSWER: D

• The Q-point for class A amplifier is at the active

region, while for class B it is at cutoff region,how about for class AB?

A. it is slightly below saturation

B. it is slightly above cutoff

C. it is slightly above saturation

D. it is at the saturation regionANSWER: B

• Where does the Q-point of a class C amplifier

positioned?

A. at saturation region

B. at active region

C. at cutoff region

D. below cutoff regionANSWER: D

• The Q-point of a class D amplifier can be set or

positioned at what region in the load line?

A. below saturation

B. above cutoff

C. at cutoff

D. any of the aboveANSWER: D



• Which of the amplifiers given below that is

considered as non-linear?

A. class A

B. class B

C. class AB

D. class C

ANSWER: D

• Which amplifiers can be used for linear

amplification?

A. class A

B. class B

C. class C

D. class A or B

ANSWER: D

• What do you call an amplifier that is biased toclass C but modulates over the same portion of

the curve as if it were biased to class B?

A. class S

B. class D

C. class AB

D. class BCANSWER: D

• Two class B amplifiers connected such that one

amplifies the positive cycle and the otheramplifies the remaining negative cycle. Bothoutput signals are then coupled by a transformer

to the load.

A. transformer-coupled push –pullamplifier

B. complementary-symmetry amplifier

C. quasi-complementary push-pullamplifier

D. transformer-coupled class A amplifierANSWER: A

• A push-pull amplifier that uses npn and pnp

transistors to amplify the positive and negativecycles respectively.



C. quasi-complementary push-pull

amplifier

D. transformer-coupled class A amplifierANSWER: B

• A push-pull amplifier that uses either npn or pnp as its final stage. The circuit configuration lookslike the complementary-symmetry.



C. quasi-complementary push-pull

amplifier

D. feed-back pair amplifierANSWER: C

• Amplifiers conversion efficiency are calculated

using what formula?

A. ac-power/dc-power

B. ac-power/dissipated power

C. dc-power/ac-power

D. A or B are correctANSWER: D

• Basically, which class of amplifiers has the least

distortion?

A. class A

B. class B

C. class C

D. class D

ANSWER: A

• A type of distortion wherein the output signaldoes not have the desired linear relation to theinput.

A. linear distortionB. nonlinear distortion

C. cross-over distortion

D. all of the above

ANSWER: B

• Distortion that is due to the inability of an

amplifier to amplify equally well all thefrequencies present at the input signal.

A. nonlinear distortion

B. amplitude distortion

C. harmonic distortion

D. cross-over distortionANSWER: B

• A nonlinear distortion in which the output

consists of undesired harmonic frequencies of theinput signal.

A. amplitude distortion

B. frequency distortion

C. cross-over distortion

D. harmonic distortionANSWER: D

• Calculate the 2nd harmonic distortion for anoutput signal having a fundamental amplitude of

3V and a 2nd harmonic amplitude of 0.3V.

A.1.0%

B. 10%

C. 23.33%

D. 43.33%ANSWER: B



• An amplifier has the following percent harmonic

distortions; D2=10%, D3=5% and D4=1%. Whatis the amplifier % THD?

A. 5.33%

B. 11.22%

C. 16.0%

D. 22.11%ANSWER: B

• Which of the following refers to the gain of a

circuit?

A. Input quantity of an amplifier divided by the output quantity.

B. The difference between the inputvoltage and the output voltage of acircuit.

C. The ratio of the output quantity to input

quantity of an amplifier.

D. The total increase in output quality overthe input quantity of an amplifier.

ANSWER: C

• The overall gain of an amplifier in cascade is

A. the sum

B. the average of each

C. the product

D. 100% the sumANSWER: C

• If three amplifiers with a gain of 8 each are incascade, how much is the overall gain?

A. 72

B. 24

C. 512

D. 8ANSWER: C

• A multistage transistor amplifier arranged in a

conventional series manner, the output of onestage is forward-coupled to the next stage.

A. cascaded amplifier

B. cascoded amplifier

C. darlington configuration

D. feed-back pair configurationANSWER: A

• A direct-coupled two-stage transistor

configuration wherein the output of the firstransistor is directly coupled and amplified by thesecond transistor. This configuration gives a very

high current gain.

A. cascade configuration

B. cascode configuration

C. darlington configuration

D. feed-back pairANSWER: C

• A two-stage transistor amplifier in which the

output collector of the first stage provides inputto the emitter of the second stage. The finaloutput is then taken from the collector of thesecond stage.

A. cascade configuration

B. cascode configuration

C. quasi-complementary

D. complementary amplifierANSWER: B

• Famous transistor amplifier configuration

designed to eliminate the so called Miller effect.

A. cascode amplifier

B. darlington amplifier

C. differential amplifier

D. complementary-symmetry

ANSWER: A

• What are the transistor configurations used in a

cascade amplifier? A. common-base and common-emitter

B. common-base and common-collector

C. common-collector and common-emitter

D. common-emitter and common-baseANSWER: D

• Transistor configuration known to have a super-

beta (β2).

A. cascade

B. cascode

C. darlington

D. differentialANSWER: C

• What is the approximate threshold voltage

between the base-emitter junction of a silicondarlington transistor?

A. 0.3 V

B. 0.6 V

C. 1.6 V

D. 3.0 VANSWER: C

• Transistor arrangement that operates like adarlington but uses a combination of pnp and npn

transistors instead of both npn.

A.differential

B. common

C. cascode

D. feedback pairANSWER: D



• An amplifier basically constructed from two

transistors and whose output is proportional tothe difference between the voltages applied to itstwo inputs.

A. differential amplifier

B. cascode amplifier

C. complementary amplifier

D. quasi-complementary amplifierANSWER: A

• An amplifier having high direct-current stabilityand high immunity to oscillation, this is initially

used to perform analog-computer functions suchas summing and integrating.

A. operational amplifier (op-amp)

B. parametric amplifier (par-amp)

C. instrumentation amplifier

D. DC-amplifierANSWER: A

• One of the most versatile and widely usedelectronic device in linear applications.

A. SCR

B. FET

C. UJT

D. op-ampANSWER: D

• It is a very high-gain differential amplifier with

very high input impedance and very low outputimpedance.

A. par-amp

B. op-amp

C. differential amp

D. complementary ampANSWER: B

• What are the possible applications of operational

amplifiers (op-amps)?

A. ac and dc-amplifiers

B. oscillators and signal conditioning

C. voltage-level detectors and comparators

D. all of the above

ANSWER: D

• An operational amplifier must have at least how

many usable terminals?

A.3 terminals

B. 5 terminals

C. 8 terminals

D. 14 terminalsANSWER: B

• The circuit at the input stage of operational

amplifiers


B. cascaded amplifier

C. current mirror

D. complementary amplifier

ANSWER: A

• An amplifier whose output is proportional to the

difference between the voltages applied to its twoinputs.


B. differencing

C. delta amp

D. cascode-amp

ANSWER: A

• In op-amps functional block diagram, whatfollows the differential amplifier?

A. cascode-amplifier

B. complementary amplifierC. level shifter

D. high gain amplifierANSWER: D

• A good op-amp has a

A. very high input resistance

B. very low input resistance

C. very high output resistance

D. very low CMRRANSWER: A

• Ideally, op-amps have infinite input resistanceand ________ output resistance.

A. infinite

B. zero

C. variable

D. a highly stabilizedANSWER: B

• How does the input of an op-amp made high?

A. by using super beta transistor at theinput differential stage

B. by using FETs at the input differentialstage

C. by connecting a very high resistance in

series with the input differential stage

D. A and B aboveANSWER: D



• What type of amplifier commonly used at the

output stage of op-amps?


B. cascade-amplifier

C. complementary amplifier

D. darlington stage amplifier

ANSWER: C

• The transistor configuration used at the output

complementary stage of most op-amps

A. cascode configuration

B. common emitter

C. common collector

D. common base

ANSWER: C

• Why do most op-amps use a common collector at

the output stage?

A. to have a higher output power

B. to have a better frequency response

C. to have a low harmonic distortion

D. to have a very low output resistanceANSWER: D

• The stage followed by the output complementaryin op-amps functional block diagram.

A. level shifter

B. phase shifter

C. current mirror

D. polarizerANSWER: A

• What is the purpose of a level shifter in op-amps?

A.to set and/or adjust the output voltageto zero when the input signal is zero

B. to set and/or adjust the input offsetvoltage to zero

C. to shift the input offset current to zero

D. all of the above

ANSWER: A

• Primarily, op-amps are operated with bipolar power supply, however, we can also use single

polarity power supply by

A. generating a reference voltage aboveground.

B. “floating” the negative supply terminal

(V-) of the op-amp.C. simply connecting the negative supply

terminal (V-) of the op-amp to ground.

D. isolating the negative supply terminal(V-) by a capacitor.

ANSWER: A

• Op-amps have two input terminals namely, the

inverting (-) and non-inverting (+) inputs. Whatis the significance of its name?

A. If a sine-wave is applied to theinverting (-) input, the output will be

inverted or shifted by 180°, while ifapplied to the non-inverting (+) there

will be no phase shift at the output.B. If pulses are applied to the inverting (-)

input, the positive pulse becomes

negative at the output and vice versa,while if applied at the non-inverting(+) there will be no reversal of the

pulse at the output.

C. In dc amplifier applications, increasinginput at the inverting (-) terminalcauses the output to decrease and vice

versa, while at the non-inverting (+)input, the output magnitude goes with

the input.

D. all of these are correct

ANSWER: D

• When the same signal is applied to both invertingand non-inverting input terminals of an ideal op-

amp, the output voltage would be

A. zero (0) V

B. +VSAT

C. –VSAT

D. offset voltageANSWER: A

• The operating mode of an op-amp, when both

inputs are tied together or when the input signalis common to both inputs.

A. differential modeB. rejection mode

C. double-ended mode

D. common modeANSWER: D

• What do you call of the gain of an op-amp ifoperated in common mode input?

A. differential gain

B. common gain

C. double-ended gain

D. rejection gainANSWER: B

• When one input of the op-amp is connected toground and the other is to the signal source, its

operation is called

A. single-ended output

B. double-ended output

C. single-ended input

D. double-ended inputANSWER: C



• If op-amps are operated in differential mode, its

gain is technically termed as

A. common-mode differential gain

B. differential gain

C. open-loop gain

D. closed-loop gain

ANSWER: B

• In op-amps, which gain is the highest?

A. common-mode gain

B. differential gain

C. closed-loop gain

D. open-loop gain

ANSWER: D

• The ratio of the differential gain and common

gain of an op-amp

A. differential-common mode ratio

B. common-mode ratio

C. differential-mode rejection ratio

D. common-mode rejection ratioANSWER: D

• An operational amplifier has a common-mode

voltage gain of 10 and a differential-modevoltage gain of 20,000, calculate its common-mode rejection ratio (CMRR).

A. 200

B. 2,000

C. 20,000

D. 200,000ANSWER: B

• Calculate the CMRR of an op-amp having a

common-mode gain of 10 and a differential-modegain of 100,000.

A. 1000 dB

B. 100 dB

C. 80 dB

D. 40 dBANSWER: C

• The non-inverting and inverting inputs of an op-

amp have an input voltage of 1.5 mV and 1.0mV, respectively. If the op-amp has a common-mode voltage gain of 10 and a differential-mode

gain of 10,000, what is its output voltage?

A.5.0 V

B. 5.0125 mV

C. 5.0125 V

D. 25.0125 VANSWER: C

• What is the maximum output voltage swing of an

op-amp?

A. +V to -V (supply voltage)

B. +VSAT to -VSAT

C. +½V to -½V

D. depends on the input signal

ANSWER: B

• The µA741 op-amp has a CMRR of 90dB and a

differential-mode voltage amplification of200,000.What is the op-amp’s common-modevoltage gain?

A. 31,622.778

B. 632.40

C. 6.324

D. 0.158ANSWER: C

• The current needed at the input of an op-amp tooperate it normally

A. input bias currentB. input offset current

C. input threshold current

D. input holding current

ANSWER: A

• Ideal op-amp requires no input current, but real

op-amp needs a very small input current calledinput bias current. At both inputs, the biascurrents have a slight difference. What do youcall this difference?

A. differential input current

B. differential bias

C. input offset difference

D. input offset currentANSWER: D

• The change in input offset current due to

temperature change

A. delta input offset current

B. slew rate

C. input offset current drift

D. PSRR

ANSWER: C

• The reason why a slight difference between the

input bias current occurs in op-amps is due to theunsymmetrical circuit component parameters.This unsymmetrical condition also produces adifference in input voltage called what?

A. drift voltage

B. differential voltage

C. input offset voltage

D. input threshold voltage

ANSWER: C



• As electronic circuit operates, its operating

temperature changes which causes device parameters to change. In op-amps, what do youcall the change in input offset voltage due to thechange in temperature?

A. input differential drift

B. input offset voltage drift

C. slew rate

D. PSRRANSWER: B

• It is known through experiment that the input bias

currents at the non-inverting (IB+) and inverting(IB-) inputs of a certain op-amp is 100 nA and 80nA, respectively. Determine the op-amp’s inputoffset current.

A. -20 nA

B. 20 nA

C. 90 nA

D. 180 nA

ANSWER: B

• Ideally, the output voltage of an op-amp is zerowhen there is no input signal, however, in

practical circuits, a small output voltage appears,this voltage is known as

A. minimum output voltage

B. pinch-off voltage

C. output offset voltage

D. saturation voltageANSWER: C

• The output offset voltage of an op-amp is (are)

due to

A. input offset currentB. input offset voltage

C. voltage and current drift


• Calculate the output offset voltage of an invertingamplifier using op-amp with an input offset

current of 10 nA. The circuit is having an input

resistance of 10 kΩ and a feedback resistance of100 kΩ.

A. 0.1 mV

B. 1.0 mV

C. 10.0 mV

D. 100.0 mVANSWER: B

• An op-amp inverting amplifier uses a feedback

resistor of 100 kΩ and input resistor of 10 kΩ. Ifthe op-amps input offset voltage is 2.0 mV,approximate the amplifier output offset voltagedue to this input offset voltage.

A. 10 mV

B. 11 mV

C. 20 mV

D. 22 mVANSWER: D

• The output offset voltage of an op-amp is due to

the input offset current and voltage. If 1 mV isdue to the input offset current and 22 mV due tothe input offset voltage, what is the total outputoffset voltage of the op-amp?

A. 11.5 mV

B. 22 mV

C. 23 mV

D. 45 mV

ANSWER: C

• How will you minimize the output offset voltagedue to the input offset current of an op-amp?

A. by installing a bias-current-compensating resistor

B. by increasing the value of the feedback

resistor

C. by decreasing the value of the inputresistor

D. B and C aboveANSWER: A

• What is a bias-current compensating resistor in

op-amp circuits? A. A resistor used to reduce the undesired

output offset voltage due to the inputoffset current.

B. A resistor connected between the non-inverting terminal and ground.

C. A resistor used to balance both input bias currents and therefore eliminatesthe input offset current.

D. all of these

ANSWER: D

• The approximate value of the bias-current

compensating resistor in op-amp circuits is

A. equal to the feedback resistorB. equal to the input resistor

C. equal to the series combination of the

input and feedback resistors

D. equal to the parallel combination of theinput and feedback resistors

ANSWER: D



• In op-amp analysis, the input offset voltage is

represented by

A. a battery

B. a signal generator

C. Thevenin’s voltage source

D. Norton’s current source

ANSWER: A

• The battery representing the input offset voltage

in op-amp circuit analysis is connected where?

A. between the inverting and groundterminal

B. between the non-inverting and ground

terminal

C. between the inverting and non-inverting terminal

D. either B and C above

ANSWER: B

• What is the effect of the input offset voltage to

the output voltage if the op-amp has no feedbackelement?

A. causes the output to be always at cutoff

B. causes the output to saturate towards

positive

C. causes the output to saturate towardsnegative

D. causes the output to saturate eithertowards positive or negative

ANSWER: D

• How can we minimize the effect of the input

offset current and input offset voltage at theoutput offset voltage?

A. by making the feedback resistancesmall

B. by making the feedback resistancelarge

C. by making the input resistance small

D. by making the input resistance large

ANSWER: A

• An op-amp is wired as an inverting amplifier

with an input and feedback resistances of 1 kΩ

and 100 kΩ, respectively. When the input signalis set to zero, the output was found to have anoffset voltage of 101 mV. Calculate the input

offset voltage.

A. 0.01 mVB. 0.1 mV

C. 1.0 mV

D. 10.0 mVANSWER: C

• What is the most effective way of minimizing the

output offset voltage of an op-amp?

A. by reducing the value of the feedbackresistor

B. by increasing the value of the input

resistor

C. by a capacitor-compensation technique

D. by properly using and adjusting theoffset-null terminals

ANSWER: D

• What cause(s) the well-adjusted output offset

voltage of op-amps to change?

A. change in operating temperature

B. component aging

C. variations in supply voltage

D. all of the above

ANSWER: D

• Which op-amp parameter(s) that normally

affects its small signal dc-amplification performance?

A. input bias current

B. input offset voltage

C. input offset current


• Op-amp parameter(s) that is important in large

signal dc-amplification.

A. input offset voltage

B. input offset current

C. slew rate

D. all of the aboveANSWER: C

• In large signal dc-amplifiers using op-amp,

which parameter has the least effect on its performance?

A. drift

B. slew rate

C. input offset voltage

D. input offset current

ANSWER: A

• For ac-amplifiers using op-amps what

parameters can affect its performance.

A.input offset current and voltage

B. input bias current and voltage

C. drift and slew rate

D. slew rate and frequency responseANSWER: D



• If an op-amp is used to amplify small ac-

signals, what parameter you should greatlyconsider to ensure better performance?

A. input bias current

B. drift

C. frequency response

D. slew rateANSWER: C

• What do we mean by internally compensated

op-amps?

A. Op-amps with internal frequencycompensation capacitor to prevent

oscillation.

B. Op-amps with an internal compensatingresistor to make the output offsetvoltage zero.

C. Op-amps with internal couplingcapacitor to block dc-voltages and

allows ac-voltages to pass.

D.Op-amps with internal activecomponents to make its gain constant atthe entire operating frequency.

ANSWER: A

• The frequency at which the open-loop gain ofan op-amp is 0.707 times its value at very lowfrequency

A. threshold frequency

B. break frequency

C. minimum frequency

D. operating frequencyANSWER: B

• What will happen to the voltage gain of op-amp when its operating frequency is increased?

A. also increases

B. increases exponentially

C. will decrease

D. decreases exponentially

ANSWER: C

• The reduction of op-amps gain due toincreasing operating frequency.

A. Cutoff

B. roll-off

C. diminishing factor

D. reduction stepANSWER: B

• What do we mean by a 20 dB/decade roll-off?

A. a gain reduction by a factor of 10 perdecade

B. a gain reduction by a factor of 20 perdecade

C. a gain reduction by a factor of 10 per10 Hz increased in frequency

D. a gain reduction by a factor of 20 per10 Hz increased in frequency

ANSWER: A

• A reduction of op-amp’s voltage gain by a

factor of two each time the frequency doubles.

A. 2 dB/octave

B. 2 dB/decade

C. 6 dB/octave

D. 6 dB/decade

ANSWER: C

• Frequency at which the voltage gain of op-amp

reduces to unity. A. unity-gain frequency

B. cutoff frequency

C. bandwidth point

D. unity-gain bandwidth productANSWER: D

• The low and high cutoff frequencies of an

amplifier is also called

A. corner frequencies

B. 0.707 frequencies

C. 3-dB frequencies

D. all of these are correctANSWER: D

• Calculate the cutoff frequency (f c)of an op-

amp having a unity-gain bandwidth product B1 = 1 MHz and a open-loop voltage gain AOL =

100,000.

A. 10 Hz

B. 20 Hz

C. 100 Hz

D. 200 Hz

ANSWER: A

• An op-amp has a specified transient response

rise time of 0.3 µs, calculate its unity-gain bandwidth.

A. 0.857 MHz

B. 1.0 MHz

C. 1.167 MHz

D. 2.334 MHzANSWER: C



• Rise time is defined as the time required for

the output voltage to rise from _______ to ________ of its final value.

A. 0% - 100%

B. 1% - 99%

C. 5% - 95%

D. 10% - 90%ANSWER: D

• The maximum output voltage rate of change of

an op-amp.

A. rise time

B. maximum voltage swing

C. differential rate

D. slew rate

ANSWER: D

• Factor(s) or parameter(s) that determine(s) theop-amps maximum operating temperature

A. PSRR

B. slew rateC. unity-gain bandwidth product

D. B and C aboveANSWER: D

• What is the maximum signal frequency thatcan be used in an op-amp having a specified

slew rate of 0.5 V/µsec? The maximum outputvoltage desired is 5 V.

A. 16 kHz

B. 32 kHz

C. 100 kHz

D. 1 MHzANSWER: A

• What must be the slew rate of an op-amp to be

used in order to provide an undistorted outputvoltage of .10 V ac a frequency of 100,000

rad/sec?

A. 0.1 V/µsec

B. 0.5 V/µsec

C. 1.0 V/µsec

D. 6.28 V/µsec

ANSWER: C

• When an op-amp is used as a comparator, the

output voltage would be +VSAT if

A.V+ > V-

B. V- > V+

C. V- = V+

D. V- and V+ are both zeroANSWER: A

• Two comparators using op-amps, configured

such that it can detect voltage levels within acertain range of values rather than simplycomparing whether a voltage is above or belowa certain reference.

A. analog comparator

B. regenerative comparator

C. parallel comparator

D. window comparatorANSWER: D

• What gain is significant when an op-amp is

used as a voltage comparator?

A. open-loop gain

B. common gain

C. differential closed loop gain

D. closed loop gain

ANSWER: A

• An op-amp zero-crossing detector without

hysteresis, A. uses a resistor as its feedback element

B. uses a capacitor as its feedback element

C. uses an inductor as its feedback

element

D. has no feedbackANSWER: D

• The feedback element of a differentiator

constructed from op-amp is

A. a resistor

B. an inductor

C. a capacitor

D. an RC networkANSWER: A

• An active integrator uses an op-amp, what is

its feedback element?

A. Resistor

B. capacitor

C. inductor

D. RC networkANSWER: B

• The voltage gain of an op-amp voltagefollower.

A. unity

B. Rf/RiC. 1 + Rf/Ri

D. depends on the type of op-amp

ANSWER: A



• Calculate the closed-loop voltage gain of an

inverting amplifier having a feedback and aninput resistance of 100 kΩ and 10 kΩ,respectively.

A. 10

B. 11

C. 100

D. 110ANSWER: A

• The gain of an inverting amplifier isdetermined by the ratio of the feedback and

input resistors (Rf/Ri), meaning we can selectany value of resistors as long as its ratio is thesame. What op-amp parameter that helps usdetermine the appropriate values of these

resistors?

A. CMRR

B. PSRR

C. SR

D.input bias currentANSWER: D

• What is the noise gain of op-amps?

A. equal to the open loop gain

B. Rf/Ri

C. 1 + Rf/Ri

D. equal to the common gainANSWER: C

• A unity-gain summing amplifier has three

inputs, V1 = 1.0 mV, V2 = 1.5 mV, and V3 =2.5 mV, calculate the total output voltage.

A. 2.5 mV

B. 3.5 mVC. 4.0 mV

D. 5.0 mVANSWER: D

• The random voltage at the output of an op-ampwhich could occupy the entire bandwidth.

A. noise

B. hash

C. interference


• Which of the following of the resistor

combinations that provides lesser noise in op-amp circuits?

A. Make both the feedback and inputresistances as large as possible

B. Make the feedback as large as possible,while the input as low as possible.

C. Make the feedback as low as possible,while the input as large as possible.

D. Make the feedback and input

resistances as small as possible.ANSWER: D

• In most ac-amplifiers using op-amps, the

feedback resistor is shunted with a very smallcapacitance, what is its purpose?

A. to prevent oscillation

B. to improve stability

C. to minimize high frequency noise

D. to compensate for high frequency loss

ANSWER: C

• Approximate the noise gain of an invertingadder using op-amps if it has five inputs.

A. unity (1)

B. two (2)

C. four (4)

D. six (6)ANSWER: D

• Op-amps with internal frequency

compensation are very stable with respect tosignal frequencies. However, the trade-off forfrequency stability is (are)

A. limited small-signal bandwidthB. slow slew rate

C. limited open-loop frequency response

D. all of theseANSWER: D

• What do we mean by externally compensatedop-amps?

A. op-amps with frequency-compensationterminals

B. op-amps with provision to externallycompensate for frequency stability

C. op-amps whose gain is externally

compensated




• What is true about the external frequency-

compensation capacitor?

A. the higher its value, the wider is its bandwidth

B. the lower its value, the wider is its

bandwidth

C. the higher its value, the faster its slew

rate

D. A and C aboveANSWER: B

• Typical value of the external frequency-

compensating capacitor of op-amps.

A. 3 - 30 nF

B. 30 - 300 nF

C. 0.3 - 3.0 µF

D. 3.0 - 30 µF

ANSWER: D

• What do we mean by a general-purpose op-

amps? A. op-amps with limited unity-gain

bandwidth up to approximately 1 MHz

B. op-amps with slew rate about 0.5

V/µsec

C. op-amps that has unlimited application


• Op-amps designed to operate at high slew rate,about 2000 V/µsec and at high frequencies,

more than 50 MHz.

A. general purpose op-amps

B. high power op-amps

C. high-stability op-amps

D. high-frequency, high-slew rate op-amps

ANSWER: D

• Generally, where does hybrid op-amps found

its application?

A. for high-output voltage

B. for high-output current

C. for high-frequency


• The magnitude of the op-amps input offset

voltage before it can be classified as a low-input offset voltage op-amp

A. 0.2 mV

B. 2.0 mV

C. 2.5 mV

D. 5.0 mVANSWER: A

• Op-amps whose internal transistor biasing can

be controlled externally are categorize as

A. general purpose op-amps

B. programmable op-amps

C. variable op-amps

D. externally compensated op-amps

ANSWER: B

• What op-amp parameter(s) that can be

governed by the bias control in a programmable op-amp?

A. open-loop gain and slew rate

B. unity-gain bandwidth

C. input bias current

D. all of the above

ANSWER: D

• The most popular op-amp packages are themetal can, 8-pin DIP, and the SMT. Which ofthese corresponds to TO-99?

A. metal canB. 8-pin DIP

C. SMT

D. all of the above

ANSWER: A

• Dual-in-line or DIL package is designated as

A. TO-99

B. TO-91

C. TO-116

D. TO-220ANSWER: C

• For high density ICs involving many op-amps,

what packaging is suitable?

A. metal can

B. 14-pin DIL

C. SMT

D. flat-pack

ANSWER: C

• Example(s) of surface-mounted technology(SMT) devices.

A. PLCCs

B. SOICs

C. LCCCs

D. all of the above

ANSWER: D



• Which condition must exist for a circuit to

oscillate?

A. It must have a negative feedbacksufficient to cancel the input

B. It must have a gain of less than 1

C. It must have a positive feedbacksufficient to overcome losses

D. It must be neutralizedANSWER: C

• Which of the following is not an essential partof an oscillator?

A. Source of energy that supply the lossesin tank circuit.

B. A resistor IC combination circuit.

C. Resonant circuit consist of inductanceand capacitance.

D. Regenerative feedback circuit.ANSWER: B

• Circuits that produces alternating or pulsatingcurrent or voltage.

A. Damper

B. Generator

C. oscillator

D. mixerANSWER: C

• What do you call the oscillator circuit that uses

a tapped coli in the tuned circuit?

A. Pierce

B. Colpitts

C. Hartley

D. UltraudionANSWER: C

• What determines the resonant frequency of a

crystal?

A. external components

B. the temperature of the crystal

C. the size and thickness of the crystalmaterial

D. the hermitic seal

ANSWER: C

• Type of oscillator whose frequency is

dependent on the charge and discharge of RCnetworks.

A. Hartley oscillator

B. Copitts oscillator

C. Relaxation oscillator

D. Klystron oscillatorANSWER: C

• A microwave oscillator




D. Klystron oscillatorANSWER: D

• A self-excited oscillator in which the tank is

divided into input and feedback portions by acapacitive voltage divider.

A. Hartley capacitor



D. Klystron oscillator

ANSWER: B

• A self-excited oscillator in which the tank is

divided into input and feedback portions by aninductive voltage divider or a tapped coil.


B. Copitts oscillatorC. Relaxation oscillator

D. Klystron oscillatorANSWER: A

• A circuit usually containing two transistors ortubes in an RC-coupled amplifier, the two

active devices switch each other alternately onand off.

A. Multivibrator

B. Signal generator

C. Oscillator

D. ThyristorANSWER: A

• A multivibrator that generates one output pulse

for each input trigger pulse.

A. monostable

B. astable

C. bistable

D. tristateANSWER: A

• Monostable multivibrator is also known as

A. one shot

B. single shot

C. direct shot

D. one shot or single shotANSWER: D

• What determines the pulse time in amonostable multivibrator?

A. resistor combinations

B. capacitor combinations

C. inductor combinations

D. resistor and capacitor combinations



ANSWER: D

• A multivibrator having two stable state

A. monostable

B. bistable

C. astable

D. unstableANSWER: B

• Is also known as Eccles/Jordan circuit

A. Monostable multivibrator

B. bistable multivibrator

C. astable multivibrator

D. unstable multivibrator

ANSWER: B

• Flip-flop is actually a _______ multivibrator.

A. Monostable

B. bistable

C. astable

D. unstableANSWER: B

• Considered as a free-running multivibrator

A. monostable

B. bistable

C. astable

D. unstableANSWER: C

• One type of circuit control device which may be

manual, automatic or multi-contactA. fuse

B. breakerC. switchD. relay

ANSWER: B

• What are the primary methods of controllingelectrical power?

A. by using manual switches and rheostatsB. by using variable reactance and

transformersC. by using electronic switches, such as

diodes, transistors thyratrons, andthyristors

D. all of the above

ANSWER: D

• Common method(s) of controlling electrical power with reactance

A. switching a tapped inductorB. using a saturable reactorC. by a matching transformerD. A and B above

ANSWER: D

• A reactive device used in controlling electrical

power by using two windings on a common ironcore. The control winding is supplied with smalldc-current which causes the reactance of large ac-winding to change accordingly.

A. tapped inductorB. saturable reactor

C. auto transformerD. LVDT

ANSWER: B

• A saturable reactor with regenerative feedback.

A. tapped inductorB. auto transformerC. LVDTD. magnetic amplifier

ANSWER: D

• Thyratrons in industrial electronics refers to

____________.A. a gas-filled diodeB. a vacuum tube

C. gas-filled triodeD. an electron triode

ANSWER: C

• An electronic switch that has the highest single-

device current capacity and can withstandoverloads better.

A. ThyristorsB. ignitrons

C. SCRD. triac

ANSWER: B

• A semiconductor, electronic switch that has the

highest single-device current ratingA. thyristorB. triacC. SCR

D. QuadricANSWER: C

• The purpose of installing thyrectors across the

incoming power lines to the speed control systemis to ___________

A. cause the motor to caution

B. protect drive circuits from high voltagetransient surges

C. increase the counter emfD. allow the field winding current to

continue flowingANSWER: B

• Semiconductor devices equivalent to thyratronsare generally called

A. thyrectorB. thyristor

C. diacD. ignitron

ANSWER: B



• Using electronic devices as switches, what is(are)

the general methods of controlling electrical power?

A. phase controlB. zero-voltage switching

C. static switchingD. all of the above

ANSWER: D

• Which power control switching method thatgreatly generates RFI or EMI and is thereforelimited to low-frequency applications?

A. phase controlB. zero-voltage switching

C. inverter controlD. static switching

ANSWER: A

• One of the electronic semiconductor devices

known as diac, function asA. four terminal multi-directional switchB. two terminal bi-directional switch

C. two terminal unidirectional switchD. three terminal bi-directional switch

ANSWER: B

• Which of the trigger diodes has the highest

holding voltage?A. bidirectional-trigger diac

B. bidirectional-diode-thyristor diacC. Shockley diodeD. thyrector

ANSWER: A

• General term of electronic devices used to controlor trigger large-power switching devices.

A. thyristorB. thyrectorC. break-over devices

D. triggering devicesANSWER: C

• A break-over device that is basically a diode.

A. thyristorB. thyrectorC. thyratronD. triggering diode

ANSWER: D

• A four-element solid state device that combi9nes

the characteristics of both diodes and transistors

A. varactorB. zener diode

C. tunnel diodeD. SCR

ANSWER: D

• The most popular thyristor used in electrical

power controllersA. SCRB. triacC. SCS

D. PUT

ANSWER: A

• Find the two stable operating conditions of an

SCR.A. Conducting and non-conductingB. Oscillating and quiescent

C. NPN conduction and PNP conductionD. Forward conducting and reverse

conductingANSWER: A

• How do you stop conduction during which SCR

is also conducting?A. remove voltage gateB. increase cathode voltageC. interrupt anode current

D. reduce gate currentANSWER: C

• How do we turn “ON” or trigger an SCR?

A. by making the gate (G) positive withrespect to its cathode (K)

B. by making the gate (G) positive with

respect to its anode (A)

C. by making the cathode more positivewith respect to the anode

D. A and C above

ANSWER: A

• What is true about SCRs after they are being

switched “ON”?A. The anode (A) to cathode (K) continues

to conduct even if the gate triggeringvoltage is removed.

B. The gate (G) must be provided with therequired holding current to continue itsconduction.

C. A small holding voltage at the gate is

required for a continuous conduction.D. B and C above

ANSWER: A

• The voltage across the anode (A) and cathode (K)terminals of an SCR when conducting.

A. holding voltage

B. breakdown voltageC. breakback voltageD. trigger voltage

ANSWER: A

• The minimum amount of current needed for anSCR to conduct continuously.

A. holding currentB. triggering currentC. threshold currentD. average sustaining current

ANSWER: A



• What is(are) the condition(s) in triggering SCR?

A. The gate voltage must be equal to orgreater than the triggering voltage.

B. The gate current must be equal to or

greater than the triggering current.C. The anode (A) must be positive with

respect to the cathode.D. all of the above

ANSWER: D

• The voltage decreased across the anode (A) and

cathode (K) of an SCR from non-conducting stateto conducting state.

A. holding voltageB. forward breakdown voltage

C. triggering voltage

D. breakback voltageANSWER: D

• An SCR rated 10 A is used as the controllingswitch in a circuit powered by 50Vdc. When the

SCR fires ON, its anode (A) to cathode (K)voltage was observed to be 2 V. Calculate the

breakback voltage of the SCR.A. 25 VdcB. 32 Vdc

C. 41 VdcD. 48 Vdc

ANSWER: D

• The needed voltage at the gate of an SCR beforeit conducts.

A. minimum-gate trigger voltageB. maximum-gate trigger voltageC. minimum-gate peak-inverse voltageD. maximum-gate peak-inverse voltage

ANSWER: A

• What is(are) the gate limitation(s) of SCRs andtriacs?

A. maximum-gate power dissipationB. maximum-gate peak-inverse voltageC. maximum-gate trigger current and

voltageD. all of the above

ANSWER: D

• How can we extend the rating of SCRs?A. by external coolingB. by external circuitry

C. by connecting them in series/parallelD. all of the above

ANSWER: D

• Use of heat sinks, forced air, and water cooling

are examples of external cooling in SCRs and

other devices. Which of these is the onlyrecommended to be used for the largest powerdissipating device?

A. metal heat sinksB. forced air

C. water coolingD. A and B above

ANSWER: C

• How can we increase the forward-voltage

blocking capability of SCRs?A. by connecting them in seriesB. by connecting them in parallelC. by cascading them

D. by connecting back to back in parallelANSWER: A

• In connecting two SCRs in series, during “OFF”

state, the voltage source must be properly shared between them, but due to devices’ differences,

there might be unequal voltages across each SCR.How do we equalize these voltages?

A. by installing a snubber circuitB. by adding a gate-to-cathode resistorC. by shunting a capacitor across the

anode (A) and cathode (K) of eachSCR

D. by using a blocking-equalizing resistorANSWER: D

• What is true regarding blocking-equalizingresistors in SCRs connected in series?

A. Blocking-equalizing resistors areshunted across each SCR.

B. The value of these resistors is about

10% of the value of the blockingresistance of the SCR it is shunted with.

C. These resistors increases the leakagecurrent towards the load.

D. All of the above

ANSWER: D

• A circuit used for voltage equalization during

ON-OFF switching action of SCRs in series.A. snubber circuitB. crow-bar

C. clipperD. clamper

ANSWER: A



• When a high current is needed, SCRs are

connected in parallel. The problem with paralleled SCRs is, when they are not perfectlymatched, one will conduct first before the otherand carries the full-load current that is for sure

greater than its maximum rating. To avoid thissituation, both SCRs should be turned ON at the

same time. How can we do this?A. by using high triggering gate voltage

B. by using a gate-triggering transformerC. by using reactorsD. all of the above are possible

ANSWER: D

• In controlling electrical power using phase

control method with SCR/triac being the activedevice, what do we call the period of the cycle

before the device switches to conduction?A. trigger timeB. trigger delay time

C. firing frequencyD. firing delay angle

ANSWER: D

• How many times per second does an SCR isturned ON and OFF when it is operated in a full-wave phase control at a line frequency of 60 Hz?

A. 30 timesB. 60 times (HV)C. 90 times

D. 120 times (FW)ANSWER: D

• A three terminal device that behaves roughly like

SCR, except that it can conduct current in eitherdirection when at ON.

A. thyristor

B. SUSC. SBSD. GTO

ANSWER: C

• What is the difference between a triac and asilicon bilateral switch (SBS)?

A. An SBS is usually used as breakoverdevice, while a triac is a loadcontrolling device.

B. An SBS is for low voltage applications,

while a triac is generally for highvoltage applications.

C. An SBS has better and stable

symmetrical-firing voltage than a triac.D. all of the above

ANSWER: D

• A triac can be triggered ON by the application ofa

A. positive voltage at the gate with respectto MT1

B. negative voltage at the gate with

respect to MT1C. positive or negative gate voltage with

respect to MT2D. all of the above are correct

ANSWER: D

• Which are the three terminals of a TRIAC?

A. Gate, anode 1 and anode 2B. Gate, source and sinkC. Base, emitter and collectorD. Emitter, base 1 and base 2

ANSWER: A

• What are the three terminals of a triac?

A. anode 1 (A1), anode 2 (A2) and gate(G)

B. mainterminal 1 (MT1), mainterminal 2

(MT2), and gate (G)C. anode (A), cathode (K) and gate (G)D. both A and B are acceptable

ANSWER: D

• A silicon bilateral switch may be considered as ssmall power triac, and has three terminals

namely,A. anode 1 (A1), anode 2 (A2) and gate

(G)B. mainterminal 1 (MT1), mainterminal 2

(MT2), and gate (G)C. anode (A), cathode (K) and gate (G)D. both A and B are acceptable

ANSWER: D

• A thyristor that is very similar to an SCR exceptthat it has low voltage and current ratings. It is

very temperature stable, and is therefore suitableto be used as triggering device.

A. UJTB. GTO

C. SBSD. SUS

ANSWER: D

• Silicon unilateral switches (SUSs) generally havea breakover voltage of 8 V, however, this valuecan be altered by normally connecting a zener

diode. How is the diode installed?A. across the gate (G) and cathode (K)

terminals, with the diode’s anode atthe gate

B. anode to anode, cathode to cathodeC. diode’s cathode to SUS’s anode and

diode’s anode to SUS’s cathodeD. diode’s cathode to SUS’s gate and

diode’s anode to SUS’s cathodeANSWER: D



• A silicon unilateral switch (SUS) has a forward

breakover voltage of 8 V. a zener diode isconnected between its gate and cathode terminalswith the diode’s cathode at SUS’s gate. If thezener voltage is 3.9 V, what is the new forward

breakover voltage of the device?A. 0.49 V

B. 2.05 VC. 4.50 V

D. 11.9 VANSWER: C

• Thyristor whose characteristic curve closely

resembles that of SCR’s and SUS’s, except thatits forward breakover voltage (+VBO) is not

alterable, for the device has no gate terminal.A. diac

B. thyrectorC. UJTD. Shockley diode

ANSWER: D

• What will happen to the forward breakdown or breakover voltage of SCRs and triacs if the gatecurrent is increased?

A. will decreaseB. will also increase

C. will not changeD. will either increase or decrease, it

depends on their current coefficientANSWER: A

• A UJT or unijunction transistor is a three terminal

breakover-type switching device. Its threeterminals are called base 1, base 2, and emitter.Though this is a transistor and has base andemitter terminals, this operates very different

from a BJT and is not used as a linear amplifier.Its applications are for

A. timers and oscillatorsB. signal generatorsC. triggering control for SCRs and triacs


• A UJT has an internal resistances of R B1 = 6 KΩand R B2 = 3 KΩ, what is its interbase resistance?

A. 2 KΩ

B. 3 KΩ C. 6 KΩ D. 9 KΩ

ANSWER: D

• For a unijunction transistor (UJT) to witch ON

A. the base 1 voltage should be greaterthan the peak voltage

B. the base 2 voltage should be greater

than the peak voltageC. the emitter voltage should be greater

than the peak voltageD. the voltage between the emitter and

base 1 should be greater than the peakvoltage when emitter being more

positiveANSWER: D

• Semiconductor devices with inherent ON-OFF behavior and has no linear operating regions are

called thryistors. Examples are SCRs, triacs,SUSs, SBSs, Shockley diodes, diacs, PUTs, andSCSs. In selecting thyristors for a particularapplication, which of the statement below is

generally desirable?A. thyristors with high current and

voltage ratingsB. thyristors with high holding

current/voltageC. faster thyristorsD. thyristors with high breakback-voltage

ANSWER: D

• Why does thyristors with high breakback voltagedesirable?

A. it dissipates less powerB. it generates less heatC. it is more efficientD. all of the above

ANSWER: D

• Portion in the welding process interval during

which the welding current is flowing is called ____________.

A. cool sub-intervalB. released interval

C. squeeze intervalD. heat sub-interval

ANSWER: D

• In automatic welding system, basically there arehow many intervals?

A. 2B. 5C. 10

D. 15ANSWER: B

• In automatic welding what do you call the first

interval wherein the material to be welded areheld together?

A. squeeze intervalB. weld interval

C. hold intervalD. standby interval

ANSWER: A



• After the squeeze interval, what comes next in an

automatic welding system?A. squeeze intervalB. weld interval


ANSWER: B

• During the welding or weld interval, when awelding current is flowing the system is said to

be at

A. weld intervalB. cool subintervalC. heat subinterval

D. hold intervalANSWER: C

• The portion of the weld interval during which the

current is absentA. cool subintervalB. heat subinterval


ANSWER: A

• After the welding interval, it goes to _________

interval wherein the electrode pressure ismaintained on the metal surfaces.

A. cool subintervalB. heat subintervalC. hold intervalD. standby interval

ANSWER: C

• Next to hold interval is __________ interval in

automatic welding system.A. squeezeB. coolC. standby

D. releaseANSWER: D

• After the release interval in automatic welding,

the system will go toA. cool intervalB. squeeze interval

C. standby intervalD. hold interval

ANSWER: C

• Refers to the system that has no feedback and isnot self correcting

A. Close-loop systemB. Coal slurry systemC. Feed forward control systemD. Open-loop system

ANSWER: D

• The system is ____________ if a position servo

system does not respond to small changes in theinput.

A. under stabilized

B. underdampedC. stabilized

D. overdamped

ANSWER: D

• What is the purpose of using a differentialsynchro instead of a regular synchro?

A. Handles more signals only

B. Performs addition and subtractionfunction only

C. Differential synchros can handle moresignals and also performs addition and

subtraction functionD. Handles two signals only

ANSWER: C

• Industrial circuit or system that is not self-correcting

A. open-loopB. closed-loopC. system with feed backD. non-servo

ANSWER: A

• What do you call a circuit or system that is self-

correcting?A. open-loop

B. closed-loopC. system without feed back

D. servoANSWER: B

• Open-loop in control system means:

A. it has no feedbackB. it is not self-correctingC. it is not self-regulating

D. all are correctANSWER: D

• In control system, closed-loop means:

A. it has feedbackB. it is self-correctingC. it is self-regulating

D. all are correctANSWER: D

• When a closed-loop system is used to maintain

physical position it is referred asA. gyro system

B. feedback systemC. servo systemD. differential system

ANSWER: C



• In closed-loop system, what do you call the

difference in the measured value and the set valueor desired value?

A. errorB. differential voltage

C. potential differenceD. threshold

ANSWER: A

• Error signal in closed-system is also known asA. difference signalB. deviation

C. system deviationD. all are correct

ANSWER: D

• In a closed-loop control system, when the errorsignal is zero the system is at

A. nullB. saturationC. cut-offD. halt

ANSWER: A

• The small error signal or system deviation where

the system cannot correct anymoreA. thresholdB. holdingC. offset

D. biasANSWER; C

• A good closed-loop control system has the

following characteristicsA. with very small offset signal or voltageB. quick response

C. highly stableD. all are correct

ANSWER: D

• In control system, the manner in which thecontroller reacts to an error is termed as

A. mode of operation

B. type of operationC. mode of controlD. reaction style

ANSWER: C

• What are the general basic modes of control in

control system?A. On-Off

B. ProportionalC. Proportional plus integral

D. Proportional plus derivativeANSWER: D

• Mode of control wherein the controller has only

two operating states. This mode is also known as bang-bang control.

A. On-OffB. Proportional

C. Proportional plus integralD. Proportional plus derivative

ANSWER: A

• ____________ is a mode of control wherein thecontroller has a continuous range of possible

position, not just two as in bang-bang control.

A. On-OffB. ProportionalC. Proportional plus integralD. Proportional plus derivative

ANSWER: B

• Proportional mode of control wherein the

controller is not only considering the magnitudeof the error signal but as well as the time that ishas persisted.

A. On-OffB. ProportionalC. Proportional plus integral *D. Proportional plus derivative

ANSWER: C

• Proportional mode of control wherein the

controller is not only considering the magnitudeof the error signal but as well as its rate of

change.A. Proportional

B. Proportional plus integralC. Proportional plus derivative *D. Proportional plus integral plus

derivative

ANSWER: C

• What is (are) being considered in Proportional

plus Integral plus Derivative (PID) mode ofcontrol?

A. error signal magnitudeB. error signal period of occurrence

C. error signal rate of changeD. all are considered *

ANSWER: D

• If On-Off mode of control is the simplest, what isits opposite or the most complex?

A. Proportional

B. Proportional plus integralC. Proportional plus derivativeD. Proportional plus integral plus

derivative *

ANSWER: D

• The __________ are two of the most common

mechanical configuration of industrial robots.A. Spherical and pneumaticB. Articulated arm and cylindrical *C. Spherical and hydraulic



D. Jointed-arm and electricANSWER: B

• One advantage of hydraulic actuator in industrialrobots include _____________.

A. great force capability handling heavyloads *

B. lower operating cost than the other typeC. low initial cost than the other type

D. clean-no oil leaksANSWER: A

• ____________ includes tow of the actuator type

used in industrial robots.A. Pneumatic and Jointed-arm

B. Hydraulic and PneumaticC. Electric and Spherical

D. Hydraulic and CylindricalANSWER: B

• A system in which the precise movement of alarge load is controlled by a relatively weak

signal.A. hydraulicB. electroC. synchroD. servo

ANSWER: D

• A programmable, multifunction manipulator

designed to move materials, parts, tools orspecific devices.

A. Industrial robot

B. AndroidC. ActuatorD. End effector

ANSWER: A

• The technology for automations

A. avionicsB. cryogenics

C. cryotronicsD. robotics

ANSWER: D

• What is(are) the common mechanicalconfigurations for industrial robots?

A. articulated-arm or jointed-armB. spherical configurationC. cylindrical configurationD. all of these

ANSWER: D

• The number of axis a robot is free to move is

calledA. freedom axisB. degrees of freedom

C. movement degreesD. mechanical axis

ANSWER: B

• Actuators used in industrial robots

A. electric motorsB. fluid motors

C. fluid cylindersD. all of these are correct

ANSWER: D

• Which of the actuators that has the greatest forcecapability?

A. electricB. hydraulic fluidC. pneumatic

D. magneticANSWER: B

• Actuator that requires the highest initial cost:

A. electricB. hydraulic

C. pneumaticD. magnetic

ANSWER: B

• Robot actuator that has the highest operatingcost:

A. electric

B. hydraulicC. pneumaticD. magnetic

ANSWER: B

• The most messy robot actuator:A. electric

B. hydraulicC. pneumaticD. magnetic

ANSWER: B

• Advantages of electric actuators:A. Lower initial cost than either hydraulic

or pneumaticB. Much lower operating cost than

hydraulicC. Accurate positioning and good velocity

controlD. All of these are correct

ANSWER: D

• Advantages of pneumatic actuators:A. lower initial and operating cost than

hydraulic actuatorsB. Clean, no oil leaks

C. Quick responseD. All are correct

ANSWER: D



• Advantages of hydraulic actuators

A. Great holding strength when stoppedB. Accurate positioning and good velocity

controlC. Intrinsically safe in flammable

environment such as paintingD. All of these are correct

ANSWER: D

• Disadvantages of pneumatic actuators:A. Weak force capabilityB. Not so much holding strength when

stopped as compared to hydraulicsystem

C. Accurate positioning and velocitycontrol is impossible

D. All of these are correctANSWER: D

• Disadvantages of electric actuators in industrial

robots:A. Less force capability as compared to

hydraulic systemB. Very little holding strength when

stopped which causes a heavy load tosag

C. Usually requires mechanical brakes

D. All are correctANSWER: D

• A robot software or program that produces only

two-position motion for a given robot axis.A. positive-stop

B. point-to-pointC. continuous-pathD. hard interrupt

ANSWER: A

• A robot program that has the ability to move a

robot to any position within the range but withoutspecific path.

A. positive-stop programB. point-to-point programC. continuous path program

D. compound programANSWER: B

• A robot program that has the ability to move a

robot to any position within the range withspecific path.

A. positive-stop program

B. point-to-point programC. continuous path programD. compound program

ANSWER: C

• When a robot moves on several axis at the sametime, it is to have

A. intrinsic motionB. extrinsic motion

• In robotics, SCARA means:

A. Selective Compliant Articulated RobotArm

B. Selective Compliant Assembly Robot

ArmC. Selective Computer-Actuated Robot

ArmD. A and B are correct

ANSWER: D

• SCARA Robots has how many axis of motion?

A. 2B. 4C. 6D. 8

ANSWER: B

• SCARA Robots are designed for what

applications?A. MachiningB. Welding

C. AssemblingD. Handling heavy loads

ANSWER: C

• Why is SCARA Robot attractive in industry?

A. because it is relatively cheaperB. because it can carry very heavy loads

C. because it has unlimited movementD. all of the above

ANSWER: A

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