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PART 1BASIC ELECTRICITY AND MAGNETISM

BASIC ELECTRICITY

I. Electricity

A phenomenon that is associated with the presence and motion

of electrons and other charged particles

1. Atomic Structure

Substances Matter

composed of atoms which are made up of nucleus around which

an infinitesimal charge revolves Atom a substance consisting of electrons, protons and neutrons

Element substances consisting of atoms of only one kind

Compound Combination of 2 or more different atoms or elements.

Molecule smallest part of a compound that retains the properties of the

compound

Particles of an Atom

Electron basic quantity for a negative charge

can be valence electron being the electrons of the outermost

shell can be bound electrons being the electrons of the inner bands

can be free or conduction electrons being electrons that are free

to moveProton basic quantity for positive charge

Neutron neutral particle in atom

Macro Integrate Training an Re!ie" Center El#c$r%ni&



1'2 BASIC ELECTRICITY ANG MAGNETISM

Particle Charge,Coulomb Mass, ilogram

electron -1.!2"1!

-1#

#.1!#"1!

-$1

proton %1.!2"1!-1# 1.&$"1!-2&

neutron none 1.&$"1!-2&

'able1. (lementary )articles

Bo(r Moel- planetary-like structure of representing an atom

)* +n+ ) * no. of electrons in each orbit n * +rbital number 1 for -shell, 2 for -shell,

$ for -shell and so on. +. Electrical Classifications of Material

Conuctors materials with less than / valence electrons

allows electrical current to flow easily

("ample0 Cu, Al, Au, Ag..

Insulators aterials with more than / valence electrons

prevents the flow of electrical current

Conductor insulation serves as physical shield of wire against

heat, or moisture, )lastics, glass, ceramics, rubbers etc

Semiconuctor with e"actly / valence electrons

have electrical characteristics in between conductor and

insulator

El#c$r%ni& Macro Integrate Training an Re!ie" Center



Basic Electricit! a"# Mag"etism 1'3

,. Energy bans

Energy -a energy difference between the valence and conduction band

1.1e for i 3 !.&e for 4e

/alence Ban region of the valence shell and valence electrons

Conuction Ban region where free electrons are said to be present

0orbien Ban region where no electron e"ist

II. Basic Electrical uantities

1. C(arge 56 or q7

static electricity at rest, without any motion

the result of work done in separating electrons to its atoms

coulomb5C7, unit for electrical charge named after CharlesCoulomb

1 coulomb * .28" 1!19 electrons 5e-7

Laws of Electric Chargesa. :nlike or dissimilar charges attract each other b. ike or similar charges repel each other

Coulomb$s La% ;The force between charges is proportional to the amount of charges and inversely proportional to the square of the distancebetween charges<

0 *2

21

r

121


here!61 and 62 * point charges

k * 9.#9 " 1!# =m2>C2 5?7r * distance or separation




+. Current 5I or i7

rate of charge in motion

a continuous flow of free electrons

? * 6 > t 0i.e., 1 ampere * 1 coulomb>second

Ampere5A7 is the base unit of current, named in honor to the

@rench physicist Andre Marie Ampere "C current flows only in 1 direction

AC current flows in alternate direction periodically

,. Electromoti!e 0orce 5emf or e7 force that is used to move the charged particles such as

electrons

Electric Potential the ability of a charged body to do work on charged particles

such as electrons

#oltage $#% A potential energy difference 5or simply, )..7 that e"ists across

two points which tend to cause a flow of electrons. olt 57 is the unit of potential difference and named after ?talian

physicist Alessandro #olta. 1 volt will push 1 ampere of currentthrough 1 ohm resistance

* B > 6

i.e., olt * 1 oule > Coulomb or1 =ewton D meter > Coulomb

3. Resistance 5E or r7 a property of electric circuit, material, and substance that0

1. tends to limit the amount of current that can be producedby the applied voltage

2. converts electrical energy into heat energy +hm5F7, the basic unit of resistance named after &eorge 'imon

(hm 1F* 1>1A

Resistance La"





;'he resistance of a conducting material is directly proportional to its

length 5E α 7 and inversely proportional to its cross D sectional

area 5E α ?>A7.<

R *A

L

Resistance "it( Temerature

R+ * R1 41 5 1 6T

+ 7 T

189

R+*8T:T6:8T:T6:R

10

201

+ * 1 41 5 1 6T+ 7 T189

here!E2 * resistance at temperature '1E1 * resistance at temperature '2

α1 * temperature coefficient of resistance*1> 6 ?'o?%'18 'o * inferred absolute Gero temperature coefficient

* - 2$/.8°C Annealed copper

* - 2/2°C Hard drawn copper

* - 2$°C Aluminum

'emperature Coefficients

1. )ositive 'emperature Coefficient Eesistance increases as temperature increases

)ure metals 2. =egative 'emperature Coefficient Eesistance decreases as its temperature increases

emiconductors and etal o"ides

$. Iero 'emperature Coefficient Eesistance remains constant even there is change in

temperature.


here0 E * wire resistance in FJ * resistivity in F-cm51!- F-cm for copper7

*length of the wire A *cross-sectional area




Alloys

;. Conuctance 647

Conductivity 5σ7 is the reciprocal of resistivity.

iemen 57, unit of conductance formerly known as mho

<. Imeance= Amittance= Reactance an Suscetance

Imeance 6>8 Combination of resistance and reactance in AC circuit

Amittance 6Y8 Eeciprocal of impedance

Reactance 6&8 +pposition to current offered by capacitive and inductive

elements Suscetance 6B8

Eeciprocal of reactance

?. @or2= Po"er an Energy

@or2 6@8 'he accomplishment of motion against the action of a force

which tends to oppose the motion. oule, ? unit of work or energy

1 oule * 1 =ewton-meter * 1 Coulomb > olt

(lectronvolt 5e7, unit of energy for single electron

1e*1."1!-1#

Po"er 6P8 rate of producing work or consuming energy

P * @ t * /I * I+R * /+ R Batts D the .?. unit of electric power named after )ames att

Horsepower 5Hp7 D power rating of electric motor

1 Hp * &/ Batts or !.&/ B

Energy

Ability to do work

@or heat energy0 1 cal*/19! , 1K':*&&9.1 ft-lb





* mCT where! 6 * heat

* massC * specific heatL'* change in temperature

III. Basic Electrical Electronic Comonents

1. Resistor device having known specific values of resistance in ohms5F7

that limits the amount of current flowing through it can divide the voltage in a circuit

with power rating that show how much power can be safelydissipated

Tyes

0ine tungsten "ire the resistor in an incandescent lamp

)ic2el'C(romium Alloy used as heating elements in toasters, flat irons, and other

heating resistance heating elements

0iDe Resistors!*+ Nichrome ire offers few ohms of resistance

resistance wire

,+ Carbon Composition 1>9 B to 2B in rating, and its ohmic rating can be determined by

its color code.-+ ire . ound they are very accurate and its ohmic and wattage 5above 2B7 is

painted on its covering. Can be made from a nichrome wirewound around a ceramic core.- Battage ranges from 8B to 1!! B

/+ Metal 0ilm use a thin film of metal or a metal particle mi"ture to achieve

various resistances.

/ariable Resistors*+ 1heostat two terminal variable resistor

in series with the load to vary current

,+ Potentiometer $2pot3% three terminal variable resistor





Connected in a circuit to vary the voltage.

Taper of a potentiometer refers to the way in which the

resistance changes in relation to the position of its slider

-+ Trimmer4 Trimpots a potentiometer equipped with a plastic thumbwheel, or a slot for

a screwdriver, for occasional adMustment.

)on'Linear or )on'(mic Resistors*+ Thermistors 'emperature sensitive resistors.

:ses0 protective device, temperature measurement or control.

,+ #aristors5 or #oltage "ependent 1esistors $#"1% oltage sensitive resistors.

uses0 voltage limiter

-+ Photoresistors5 or Light "ependent 1esistors $L"1% ight sensitive resistors.

:se0 sensing light, sense people or items passing a point, adMust

television picture brightness to match room light.

Carbon Resistor Color Coing

@irst significant digit econd ignificant igit

'olerance ultiplier

CLR BA)F1 BA)F+ Multilier Tolerance

Klack ! ! 1!! --

Krown 1 1 1!1 1N

Eed 2 2 1!2

2N+range $ $ 1!$ $N

Oellow / / 1!/ /N

4reen 8 8 1!8 --

Klue 1! --

iolet & & 1!& --

4ray 9 9 1!9 --





Bhite # # 1!# --

4old -- -- !.1 8N

ilver -- -- !.!1 1!N

=o Color -- -- 2!N

Table + Resistor Color Coe

+. I)FGCTR opposes change in current

allows C but blocks AC

stores energy by concentrating the magnetic field of current also known as choke

termed as solenoid for coil with more than one turn

Inuctance 6L8 property of a circuit that opposes the change in current

e"pressed in Henries5H7 for a =-turn coil wound around a certain core, it is defined as the

amount of flu" linkage of the coil per unit current through the coil 1H*1Beber>A

L*L

A)r 2

0

here! Pr * relative permeability

Q! * material permeability

A * area= * no. of turns

* length

Time Constant 6H8 +ne time constant is the amount of time for an inductor to

energiGe and de-energiGe up to $.2 N

H*R

L where! - inductance

E- resistance

Instantaneous Current of an inuctor 'he amount of current flowing through the inductor at certain

time instant

I 6t8 *R

E 615e' 6tH88





,. CAPACITR tores electric energy

)reviously called as condenser 5deprecated7

(ssentially consists of two conducting plates called electrodes

separated by a layer called dielectric.

Caacitance 6C8 an Elastance 6S8 Caacitance6C8

'he electrical siGe of the capacitor

A measure of how much electric energy a capacitor can store

e"pressed in @arads 5@7 )reviously called capacity 5deprecated7 and permittance

5obsolete7 )ermittivity5T7 is a measure of how well a dielectric will permit

the establishment of flu" lines within the dielectric

---dU dielectric material

C *E

1where!

C * capacitance in farad, @6 * charge stored in Coulomb, C( * voltage across the capacitor in volt,

C *

Ar 0

where!

To * absolute permittivity * 9.98/ " 1!-12 @>mTr * dielectric constant A * area of parallel plates, m2

d * plate separation, m





Fielectric Fielectric Constant

Air or acuum 1

)olyvinyl $.$

Aluminum +"ide &

4lass 9

'antalum 28

)aper 2 to

ica $ to 9

Ceramic 9! to 12!!'able $0 ielectric constants of material

@or multi-plate construction of capacitor0

C * 6n'18

Ar 0 where! n * no. of plates

Elastance 6S8

'he reciprocal of capacitance Has a unit of daraf

S *C

1

Gses of Caacitor Klocks C

Couples AC

@ilter 'uning

ignal 4eneration

(nergy torage

Time Constant 6H8 +ne time constant is the amount of time for an inductor to

energiGe and de-energiGe up to $.2 N

H* RC where! C * capacitance

E * resistance

C(arging an Fisc(arging Euations





/ c(arging * E 61'e'tRC8 where! ( * source voltage

/ isc(arging * E 6e'tRC

8 t * time instant

Current t(roug( Caacitor

Ic * C 6t

!8 where! ?c * current in a capacitor

dv>dt * rate of change in voltage

Energy store in an inuctor

@* C/

+ where! B * stored energy

* voltage

Caaciti!e Reactance

&c * fC2

1

where! Sc * inductive reactance

f * frequency

Total Caacitance

C series* 61

1

C5

2

1

C5 K5

nC

18'1

C arallel * C1 5 C+ 5K 5Cn

Tyes of caacitor

0iDe Caacitorsa+ Mica Capacitance values range appro"imately 1p@ to !.1P@

:sed over a wide temperature range 5-88 to %18!VC7b+ Paper )ackaged as a ;rolled sandwich<

ariety of values, 8!!p@ to 8!Q@

+perating ambient temperatures is as high as 128VC

c+ Plastic 0ilm





)lastics used include polystyrene, polycarbonate, and polyester

5ylar7 Available in typical ranges 8!!p@ to 1!P@

d+ Ceramic ow-k ceramic capacitor is widely used in temperature

compensation network High-k ceramic capacitor change their value appreciably with

temperature, dc voltage and frequencye+ Electrolytic Can be aluminum and tantalum and either polariGed or non-

polariGed :sed where large value of capacitance in a small volume is

required.

/ariable Caacitorsa+ Air variable Capacitance values ranges from a few picofarads up to 8!!p@

a"imum voltage rating is #k

b+ Trimmer :tiliGed for fine tuning an din hybrid microelectronics circuit

C(i Caacitors =o larger than a match head

olumetric efficient

Caacitor 0ailuresCatastropic A short circuit caused by dielectric breakdown or an open circuit

caused by connection failure"egradation Eesults in a gradual decrease in leakage resistance and hence

gradual increase in leakage current

t(er Parameters#oltage 1ating pecifies the ma"imum C voltage that can be applied without

the risk of damage

Temperature Coefficient ?ndicates the amount and direction of a change in capacitance

value with temperatureLea6age Current 'he current that result in the total discharge of a capacitor if the

capacitor is disconnected from the charging networkor6ing #oltage





4auss 547, cgs unit and name after )ohann 8arl 0reidrich

&auss51&&&-19887 'esla5'7, ? unit and named after Croatian engineer Ni6ola

Tesla5198-1#/$7

* % A

,. Magnemoti!e 0orce 6mmf8

Amount of magnetiGing force or magnetic potential Coercive force, needed to reduce flu" density to Gero

omain, arrangement of atoms under mmf

4ilbert54b7, cgs unit and named after illiam &ilbert 518/!-1!$7

Ampere-turn, i unit

mmf * I) where0 ? * current , = * no. of turns

3. Magnetic 0iel Intensity 6N8 Amount of magnemotive force per unit length

+ersted 5+e7, cgs unit and named after anish physicist 7ans

Christian (ersted 51&&&-19817 Ampere-turn per meter, ? unit

N *lengt(

mmf

Magnetic units Con!ersionuantity SI cgs Relation

@lu"5R7

Beber 5Bb7

a"well5"7

1 Bb *1!9 "

@lu" ensity5W7

'esla'5Bb>m27

4auss45">cm27

1'* 1!/ 4

agnetomotiveforce 5mmf7

Ampere-turn5A-t7

4ilbert54b7

1A-t*1.218& 4b

@ield trength5H7

Ampere-turn>meter

+ersted+e54b>cm7

1A-t>m*!.!128& 4bcm

'able $0 :nits Conversion

;. Permeability





Permeance 6P8 )roperty that concentrates the magnetic flu"

A measure of the ability of a magnetic circuit to permit the settingup of flu". Counterpart of Conductance in an electric circuit.

Eeluctance, reciprocal of permeance which is the limiter of the

magnetic circuit to the establishment of a magnetic flu".

Materials Accoring to Permeability

0erromagnetic Bith very high relative permeability from 8! to 8!!!

trongly magnetiGed in the same direction as magnetiGing force

("amples0 alnico, cobalt, iron, nickel, steel, ferrites

Paramagnetic Bith relative permeability slightly greater than 1

Beakly magnetiGed in the same direction as the magnetiGing

force ("amples0 aluminum, chromium, manganese, platinum

)on' Magnetic Bith permeability equals to space or vacuum permeability which

is equals to /X " 1!-& H>m Bith relative permeability equals to 1

do allow magnetism to pass through them, but they never

become magnetiGed to any noticeable degreeFiamagnetic

with relative permeability slightly less than 1 weakly magnetiGed in opposite direction as magnetiGing force

e"amples0 antimony, bismuth, copper, gold, mercury, silver, Ginc

III. Magnetic Nysteresis

1. Nysteresis the delayed reaction of the magnetiGation of a ferromagnetic

material with the change of the magnetiGing force





Plot of magnetic field : as magneti;ing force 7 is applied

+. Magnetic Analysis

Bhen ferromagnetic material is completely demagnetiGed, there

is no magnetic field within its surroundings Bhen a magnetiGing force H is applied into a demagnetiGed

ferromagnetic material, magnetic field or flu" density rises. As H

is continuously increased, K also increases until the materialsaturates.

Bhen saturation is reached, further increase in H will have very

little increase in K. )ractically this is the point of ma"imum flu"density or magnetic field.

'he magnetic field of flu" density K left after the removal of the

magnetiGing force 5H*!7 is called remanence or residualmagnetism.

'o complete demagnetiGing the material, the residual magnetism

must be counteracted by the opposite magnetiGing force. 'heamount of force that can bring the residual magnetism to Gero iscalled the coersive force+

'he material with higher residual magnetism is said to have a

good retentivity or remanence, the ability to retain magnetismwhen magnetiGing force is removed.

)ermanent magnets are constructed from material with good

retentivity, while temporary magnets, with low retentivity.

,. La"sPrinciles on Electromagnetic Inuction

0araayOs La"





;The amount of induced voltage is directly dependent on thenumber of turns of a coil and on the rate a flu9 cuts the conductor3

Kroken into two aws00araayOs 0irst La" of Electromagnetic Inuction

;'tates that electromotive force is induced whenever aconductor cuts a magnetic flu9 <

0araayOs Secon La" of Electromagnetic Inuction;The magnitude of the induced emf is proportional to the

relative rate of change of flu9 <, mathematically e"pressed as0

/ inuce * )6t 8 where! = * number of turns

dR>dt * rate of change in flu"

LenO La";'tates that the direction of the induced current produces

magnetic field that opposes the action that produced the induced current <

Nall Effect the concept whereby a small voltage is generated whenever a

conductor with current in an e"ternal magnetic field is known

@iegan Effect the effect that describes the ability of a mechanically stressed

ferromagnetic wire to recogniGed rapid switching of magnetiGation when subMected to a C magnetic field





TEST YGRSEL0 1Re!ie" uestions

1. Bhat composes all matter whether a liquid, solid or gas 5November5 *<<= 7

a. Atomsb. (lectronsc. )rotonsd. =eutrons

2. )rotons are aboutYYYY heavier than electrons 5November5 *<<> 7a. 19!! timesb. ess than thricec. ess

d. 'wice

$. ?n the periodic table, all elements are arranged in the order according totheir 5 April5 ,??/7

a. Atomic number b. alencec. =ucleusd. Characteristics

/. Bhat do you call the subatomic particle that has a mass appro"imatelyequal to that of the proton, but it has no electrical chargeZ 5 April5 ,??/7

a. Atomb. )rotonc. (lectrond. =eutron





8. 'he nucleus of an atom is made up ofYYYYY 5 April5 ,??/7a. )rotons and electronsb. (lectrons onlyc. (lectrons and neutronsd. )rotons and neutrons

. Eefers to the atom that losses an electron $November5 ,??-7a. )ositive ionb. =egative ionc. (mf d. =eutron

&. Bhat is the symbol for carbon dio"ideZ 5November5 ,??=%

a. C+

b. C2+

c. C+2

d. Co2

9. 'he definite discrete amount of energy required to move an electron fromlower shell to another shell 5November5 *<<<%

a. =egative energyb. )ositive energyc. 6uantumd. 6uanta

#. 'he force between two magnetic poles in relation to their pole strengthisYYYYYYYY 5November5 *<<<%

a. =ot relatedb. ?nversely proportionalc. irectly proportionald. ?ndependent

1!. How are static charges createdZ 5November5 ,??-%a. Ky motionb. Ky frictionc. Ky immersiond. Ky conduction

11. ery few metals are now used in their pure state. A mi"ture of two or more metals or a mi"ture of metal and another material is calledZ5November5 ,??-%

a. Alloyb. Colloidc. Compoundd. Amalgam





12. Bhich of the following statement is trueZ 5November5 ,??-7a. An increase in the temperature does not affect the resistanceb. An increase in temperature lowers the resistancec. An increase in temperature increases the resistanced. An increase in temperature doubles the resistance

1$. ?t e"hibits positive temperature coefficient 5 April5 ,??/%a. Conductor b. 4lassc. emiconductor d. uperconductor

1/. Bhich material has more free electronsZ 5November5 *<<<7a. icab. ielectricc. ?nsulatorsd. conductor

18. Bhich of the following is not a good conductor of electricity $April5 ,??/%a. ilver b. Copper c. Aluminumd. ica

1. An insulator is a substance thata. +ffers a resistance to current flowb. +ffers a low resistance to current flowc. Absorbs electricityd. @orms a condenser

1&. 'he total resistance of two similar wire conductors connected in parallelis YYYYY. 5November5 *<<<7

a. ame resistance of 1 wireb. ouble the resistance of 1 wirec. +ne half the resistance of 1 wired. Eesistance of 1 wire multiplied by /

19. A rheostat is a device that regulates the strength of an electric current by$November5 ,??-7

a. ?ncreasing the magnetic field in the circuitb. arying the voltage in the circuitc. arying the resistance in the circuitd. arying the current in the circuit

1#. 'he reciprocal of capacitance is calledYYYYYYYY5November5*<<= 7a. (lastance





b. )ermitivittyc. )ermeabilityd. Conductance

2!. Bhich of the following describes the action of capacitor 5 April5 *<<@%a. Converts AC to Cb. Creates a C resistancec. tores electrical energyd. +pposes change in current flow

21. 'he following are the factors that affect the inductance of a coil 5 April5,??/7

1. 'he number of turns in a coil2. 'he diameter of a coil$. 'he coil length/. 'he number of layers of windings in the coil8. 'he type of core material

a. 1,2,$ and / onlyb. 1,2,$ and 8 onlyc. 1,2,$,/ and 8d. 1,2,/ and 8 only

22. ?nserting a soft iron core into a coil has what effect on the inductance of the coilZ 5November5 ,??-7

a. ?ncrease inductanceb. ecrease inductancec. oes not affect the inductanced. =one of these

2$. Bhich of the following characteriGes inductanceZ 5 April5 *<<@ 7a. 'ends to oppose Cb. 'ends to oppose change in currentc. 'ends to oppose change in voltaged. +pposes all frequencies equally

2/. Bhat law in electronics where an induced current will be in such adirection that its own magnetic field will oppose the magnetic field thatproduces the sameZ





a. (lectromagnetic lawb. =orton[s lawc. enG[s lawd. a"well[s law

28. Bhat is the unit of magnetic flu" in ? systemZa. Beber b. a"wellc. 'eslad. 4auss

2. aterials with permeabilities slightly less than that of free space arereferred to as

a. iamagneticb. @erromagneticc. =on-magneticd. )aramagnetic

2&. olve for flu" density 5in gauss7 from a magnetic flu" of 8,!!! " througha perpendicular area of 2 cm " 8 cm.

a. 8,!!! 4b. 8!! 4c. 1!,!!! 4d. 8! 4

29. Bhat is the law that determines polarity of an induced voltageZa. =orton[s lawb. 'hevenin[s lawc. enG[s lawd. @araday[s law

2#. 'he natural magnet refers to 5November5*<<<%a. teelb. oft ironc. agnesiad. odestone

$!. ?t is the air space between poles of magnet 5 April5 *<<@ 7a. Air gapb. acuumc. @ree Goned. @ree space

$1. Bhere do you classify hydrogen as a materialZ 5November5 *<<<7a. iamagnetic





b. )aramagneticc. =on-magneticd. @erromagnetic

$2. Bhat is the law whereby the attraction or repulsion between twomagnetic poles is directly proportional to their strengthZ 5 April5 *<<@ 7

a. Coulomb[s lawb. =ewton[s lawc. Coulomb[s first lawd. =orton[s law

$$. YYYYYYYYY is the property of magnetic materials which retain magnetismafter magnetiGing force is withdrawn.

a. Eeluctivityb. Eesistivityc. Eetentivityd. Conductivity

$/. )ermeability is the YYYYYYYYY 5 April5 ,??/%a. )ower found in the electromagnetb. )ower found in the magnetic fieldc. (ase with which metals maybe magnetiGed or demagnetiGedd. )ower found in the transformer

$8. (lectric energy refers to YYYYYYYYYY.a. oules divided by timeb. olt-Coulombc. olt-Ampered. Batt

$. (lectric power refers toYYYYYYYY 5November5 *<<%a. ouleb. olt-amperec. Batt-secondd. olt-coulomb

$&. 'he current of electric circuits is analogous to YYYYYYYYYY parameter of a magnetic circuit.

a. @lu" densityb. Eeluctivityc. mf d. @lu"

$9. Bhich of the following refers to the point where the intensity of magneticlines of force is ma"imumZ

a. agnetic pole





b. Beak polec. =orth poled. 4reat circle

$#. Bhich one is the paramagnetic materialZ 5November5 *<< 7a. Copper b. +"ygenc. Carbond. Kismuth

/!. Bhat is the term used to e"press the amount of electrical energy storedin an electrostatic fieldZ

a. oltsb. Battsc. Coulombsd. oules

/1. Bhen you demagnetiGe properly by applying an AC field and thengradually reduced it to Gero, it is calledYYYYYY 5November5 *<< 7

a. ampingb. ecayingc. egaussingd. 4aussing

/2. Bhat is the flu" density in gauss 547 having a flu" of 12,!!! " througha perpendicular area of cm squaredZ

a. 2!!! 4b. &2!!! 4c. &2 4d. 2!! 4

/$. Bhat is another term for magnetic lines of forceZa. @lu"b. agnetic polec. Armatured. odestone

//. A magnet that is heated will YYYYY 5November5 ,??-%a. ?ncrease in magnetismb. ecrease in magnetismc. =ot change in magnetismd. Kecome demagnetiGed

/8. Bhat is the name of the effect of some of the magnetic field leaking off due to less than 1!! percent couplingZ





a. (ddy currentsb. (lectromagnetic effectc. eakage reactanced. elf inductance

/. 'he difference between the charges in the conductor is equal to thedifference in potential. 'his voltage caused in the moving magnetic field iscalled 5November5,??-%

a. (lectromagnetic forceb. ?nduced voltagec. (lectromotive forced. Counter-electromotive force

/&. 'he basic unit of measuring electrical power $November5 ,??-7a. Battb. Batt-hour c. oltd. Ampere

/9. Bhich of the following does not refer to electric energyZa. ouleb. Batt secondc. olt coulombd. olt ampere

/#. ?t is composed of a series of energy levels containing the valenceelectrons.5November5*<<<%

a. Conduction bandb. @orbidden bandc. ide bandd. alence band

8!. ?t has a unit of electronvolta. Chargeb. (nergyc. Currentd. )otential difference





\

A)S@ERS to TEST YGRSEL0 1

1. a+. a,. a3. ;. <. a?. cQ. c. c

1. b

11. a1+. c1,. a13. 1;. 1<. a1?. c

1Q. c1. a+. c

+1. c++. a

+3. c+;. a+<. a+?. b+Q. c+. ,. a

,1. c,+. c,,. c,3. c,;. b

,?. ,Q. a,. c3.

31. c3+. a3,. a33. b

3;. c3<. b3?. a3Q. 3. ;. b

part 1-elec buk

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