halliday, resnick, and walker, fundamentals of physics 10e ... · chapter 27 circuits reading quiz...
TRANSCRIPT
Halliday, Resnick, and Walker, Fundamentals of Physics 10e Question Answers
Chapter 27 Answers
1 (a) equal; (b) more
2 (a) no;
(b) yes; (c) all tie
3 parallel, R2, R1, series
4 (a) b and d tie, then a tie of a, c, and e;
(b) b, d, then a tie of a, c, and e; (c) positive x direction
5 (a) series;
(b) parallel; (c) parallel
6 2.0 A
7 (a) less;
(b) less; (c) more
8 (a) 3R; (b) R/3; (c) same
9 (a) parallel; (b) series
10 60 C
11 (a) same;
(b) same;
(c) less; (d) more
12 1, c; 2, a; 3, d; 4, b
13 (a) all tie; (b) 1, 3, 2
10/25/2018
1
Halliday/Resnick/Walker
Fundamentals of Physics
Classroom Response System Questions
Chapter 27 Circuits
Reading Quiz Questions
27.2.1. Which one of the following statements concerning emf is true?
a) Emf is the work done in moving the current from one terminal to the
other of an emf device.
b) Emf is the work done in moving a single charge from one terminal to the
other of an emf device.
c) Emf is the force exerted on a single charge to move it from one terminal
to the other of an emf device.
d) Emf is the total charge moving from one terminal to the other of an emf
device.
e) Emf is the electromagnetic force that is exerted between the terminals of
an emf device.
27.2.1. Which one of the following statements concerning emf is true?
a) Emf is the work done in moving the current from one terminal to the
other of an emf device.
b) Emf is the work done in moving a single charge from one terminal to the
other of an emf device.
c) Emf is the force exerted on a single charge to move it from one terminal
to the other of an emf device.
d) Emf is the total charge moving from one terminal to the other of an emf
device.
e) Emf is the electromagnetic force that is exerted between the terminals of
an emf device.
27.3.1. What is the primary difference between an ideal emf device and a
real emf device?
a) The electric potential of a real emf device is limited.
b) The resistance of a real emf device is finite, but the resistance of an ideal
emf device is assumed to be infinite.
c) A real emf device can carry an electric current, but an ideal emf device
does not.
d) A real emf device has an internal resistance, but an ideal emf device does
not.
e) A real emf device has a potential difference across its terminals, but an
ideal emf device does not.
27.3.1. What is the primary difference between an ideal emf device and a
real emf device?
a) The electric potential of a real emf device is limited.
b) The resistance of a real emf device is finite, but the resistance of an ideal
emf device is assumed to be infinite.
c) A real emf device can carry an electric current, but an ideal emf device
does not.
d) A real emf device has an internal resistance, but an ideal emf device does
not.
e) A real emf device has a potential difference across its terminals, but an
ideal emf device does not.
10/25/2018
2
27.3.2. Which one of the following units is the correct SI unit for the
electromotive force (emf)?
a) newtons (N)
b) coulombs (C)
c) joules (J).
d) amperes (A)
e) volts (V)
27.3.2. Which one of the following units is the correct SI unit for the
electromotive force (emf)?
a) newtons (N)
b) coulombs (C)
c) joules (J).
d) amperes (A)
e) volts (V)
27.3.3. The positive terminal of a battery in a minivan has an electric
potential that is a maximum of 12 V higher than the negative
terminal. Complete the following sentence: When wires are
connected to the battery from the various electrical circuits within
the minivan, the potential difference between the two terminals is
a) equal to 12 V.
b) less than 12 V.
c) greater than 12 V.
d) equal to zero V.
27.3.3. The positive terminal of a battery in a minivan has an electric
potential that is a maximum of 12 V higher than the negative
terminal. Complete the following sentence: When wires are
connected to the battery from the various electrical circuits within
the minivan, the potential difference between the two terminals is
a) equal to 12 V.
b) less than 12 V.
c) greater than 12 V.
d) equal to zero V.
27.3.4. Which one of the following terms describes the resistance that
a battery (or other emf device) has in a circuit?
a) super resistance
b) critical resistance
c) internal resistance
d) terminal resistance
e) electroresistance
27.3.4. Which one of the following terms describes the resistance that
a battery (or other emf device) has in a circuit?
a) super resistance
b) critical resistance
c) internal resistance
d) terminal resistance
e) electroresistance
10/25/2018
3
27.4.1. In analyzing electric circuits containing a battery and at least
one resistor, what is the change in potential across a resistor as one
moves through it in the direction of the current?
a) +i2R
b) −i2R
c) +iR
d) −iR
e) zero
27.4.1. In analyzing electric circuits containing a battery and at least
one resistor, what is the change in potential across a resistor as one
moves through it in the direction of the current?
a) +i2R
b) −i2R
c) +iR
d) −iR
e) zero
27.4.2. In analyzing electric circuits containing an ideal emf device
that has an emf and at least one resistor, what is the change in
potential across the emf device as one moves through it in the
direction of the emf arrow?
a) +
b) −
c) + / R
d) − / R
e) zero
27.4.2. In analyzing electric circuits containing an ideal emf device
that has an emf and at least one resistor, what is the change in
potential across the emf device as one moves through it in the
direction of the emf arrow?
a) +
b) −
c) + / R
d) − / R
e) zero
27.4.3. Complete the following statement: Around any closed-circuit
loop, the sum of the potential drops
a) dramatically with the addition of each resistor.
b) in each loop is the same.
c) equals the sum of the potential rises.
d) equals the emf of the battery.
e) increases with the addition of each resistor.
27.4.3. Complete the following statement: Around any closed-circuit
loop, the sum of the potential drops
a) dramatically with the addition of each resistor.
b) in each loop is the same.
c) equals the sum of the potential rises.
d) equals the emf of the battery.
e) increases with the addition of each resistor.
10/25/2018
4
27.5.1. Which one of the following statements is true concerning
resistors connected in series within an electric circuit?
a) The potential difference across each of the resistors is the same.
b) The current through each of the resistors is the same.
c) The energy dissipated by each of the resistors is the same.
d) The resistance of each of the resistors is the same.
e) The resistivity of each of the resistors is the same.
27.5.1. Which one of the following statements is true concerning
resistors connected in series within an electric circuit?
a) The potential difference across each of the resistors is the same.
b) The current through each of the resistors is the same.
c) The energy dissipated by each of the resistors is the same.
d) The resistance of each of the resistors is the same.
e) The resistivity of each of the resistors is the same.
27.5.2. Two identical resistors are connected in series across the
terminals of a battery with a voltage V and a current i flows
through the circuit. If one of the resistors is removed from the
circuit and the remaining one connected across the terminals of the
battery, how much current would flow through the circuit?
a) 4i
b) 2i
c) i
d) i/2
e) i/4
27.5.2. Two identical resistors are connected in series across the
terminals of a battery with a voltage V and a current i flows
through the circuit. If one of the resistors is removed from the
circuit and the remaining one connected across the terminals of the
battery, how much current would flow through the circuit?
a) 4i
b) 2i
c) i
d) i/2
e) i/4
27.5.3. One end of resistor A is connected to the positive terminal of a
battery and the other end is connected to resistor B. The opposite
end of resistor B is connected to the negative terminal of the
battery. If resistor A has resistance R and B has a resistance 2R,
what is the equivalent resistance of this circuit?
a) R
b) 3R/2
c) 2R
d) 2R/3
e) 3R
27.5.3. One end of resistor A is connected to the positive terminal of a
battery and the other end is connected to resistor B. The opposite
end of resistor B is connected to the negative terminal of the
battery. If resistor A has resistance R and B has a resistance 2R,
what is the equivalent resistance of this circuit?
a) R
b) 3R/2
c) 2R
d) 2R/3
e) 3R
10/25/2018
5
27.6.1. Which of the following occurs when part of an electric circuit
is connected to ground?
a) The ground acts like a battery, so the current in the circuit
increases.
b) Any current in the circuit flows to the ground.
c) The electric potential at the connection point is equal to zero volts.
d) The electric potential difference across the terminals of any
batteries in the circuit is equal to zero volts.
e) The ground provides a source for more electrons to flow into the
circuit.
27.6.1. Which of the following occurs when part of an electric circuit
is connected to ground?
a) The ground acts like a battery, so the current in the circuit
increases.
b) Any current in the circuit flows to the ground.
c) The electric potential at the connection point is equal to zero volts.
d) The electric potential difference across the terminals of any
batteries in the circuit is equal to zero volts.
e) The ground provides a source for more electrons to flow into the
circuit.
27.7.1. While analyzing the currents within a circuit containing multiple
components (such as batteries, resistors, etc.), which of the following
statements concerning currents flowing into a single junction must be true?
a) The sum of the currents entering the junction must equal the total current
through the battery.
b) The sum of the currents entering the junction must equal zero.
c) The sum of the currents entering the junction must equal the sum of the
currents exiting the junction.
d) The currents entering the junction must follow only one of the possible exit
paths.
e) The currents entering the junction may exit back along the path from which
they entered.
27.7.1. While analyzing the currents within a circuit containing multiple
components (such as batteries, resistors, etc.), which of the following
statements concerning currents flowing into a single junction must be true?
a) The sum of the currents entering the junction must equal the total current
through the battery.
b) The sum of the currents entering the junction must equal zero.
c) The sum of the currents entering the junction must equal the sum of the
currents exiting the junction.
d) The currents entering the junction must follow only one of the possible exit
paths.
e) The currents entering the junction may exit back along the path from which
they entered.
27.7.2. The fact that the sum of the currents entering any junction in an
electric circuit must be equal to the sum of the currents leaving the
junction is an expression of what principle?
a) conservation of energy
b) Heisenberg uncertainty principle
c) conservation of momentum
d) Archimedes' Principle
e) conservation of charge
27.7.2. The fact that the sum of the currents entering any junction in an
electric circuit must be equal to the sum of the currents leaving the
junction is an expression of what principle?
a) conservation of energy
b) Heisenberg uncertainty principle
c) conservation of momentum
d) Archimedes' Principle
e) conservation of charge
10/25/2018
6
27.7.3. Which one of the following statements is true concerning
resistors connected in parallel within an electric circuit?
a) The potential difference across each of the resistors is the same.
b) The current through each of the resistors is the same.
c) The energy dissipated by each of the resistors is the same.
d) The resistance of each of the resistors is the same.
e) The resistivity of each of the resistors is the same.
27.7.3. Which one of the following statements is true concerning
resistors connected in parallel within an electric circuit?
a) The potential difference across each of the resistors is the same.
b) The current through each of the resistors is the same.
c) The energy dissipated by each of the resistors is the same.
d) The resistance of each of the resistors is the same.
e) The resistivity of each of the resistors is the same.
27.7.4. Which of the following statements concerning resistors that are
wired in parallel is true?
a) The current through each resistor is necessarily the same.
b) The equivalent resistance for the resistors in the circuit is the sum
of the individual resistances.
c) The voltage across each resistor is necessarily the same.
d) The equivalent resistance for the resistors in the circuit is the
product of the individual resistances.
e) The equivalent resistance for the resistors in the circuit is the
average of the individual resistances.
27.7.4. Which of the following statements concerning resistors that are
wired in parallel is true?
a) The current through each resistor is necessarily the same.
b) The equivalent resistance for the resistors in the circuit is the sum
of the individual resistances.
c) The voltage across each resistor is necessarily the same.
d) The equivalent resistance for the resistors in the circuit is the
product of the individual resistances.
e) The equivalent resistance for the resistors in the circuit is the
average of the individual resistances.
27.7.5. Two resistors can be either connected to a battery in series or in
parallel. In which case, if either, is the equivalent resistance the
smallest?
a) When the two resistors are wired in parallel, the equivalent resistance
is less than if they are wired in series.
b) When the two resistors are wired in series, the equivalent resistance is
less than if they are wired in parallel.
c) Both series and parallel wiring will result in the same equivalent
resistance.
d) It is not possible to know which method of wiring will result in the
lowest equivalent resistance without knowing the values of the two
resistances.
27.7.5. Two resistors can be either connected to a battery in series or in
parallel. In which case, if either, is the equivalent resistance the
smallest?
a) When the two resistors are wired in parallel, the equivalent resistance
is less than if they are wired in series.
b) When the two resistors are wired in series, the equivalent resistance is
less than if they are wired in parallel.
c) Both series and parallel wiring will result in the same equivalent
resistance.
d) It is not possible to know which method of wiring will result in the
lowest equivalent resistance without knowing the values of the two
resistances.
10/25/2018
7
27.7.6. In analyzing circuits in which resistors are wired partially in series and
partially in parallel, which one of the following statements describes the
preferred approach to take to determine the equivalent resistance in the circuit?
a) Find the sum of all the resistors. This is the equivalent resistance for the circuit.
b) Break the circuit into smaller parts and find an equivalent resistance for each part.
Then continue this process until all of the parts are added together correctly
either in series or parallel until a single equivalent resistance is found.
c) All together all of the resistors in series, ignoring any wired in parallel as they do
not significantly add to the equivalent resistance of the circuit. The sum of the
resistors in series is the equivalent resistance.
d) All together all of the resistors in parallel, ignoring any wired in series as they do
not significantly add to the equivalent resistance of the circuit. The sum of the
resistors in parallel is the equivalent resistance.
27.7.6. In analyzing circuits in which resistors are wired partially in series and
partially in parallel, which one of the following statements describes the
preferred approach to take to determine the equivalent resistance in the circuit?
a) Find the sum of all the resistors. This is the equivalent resistance for the circuit.
b) Break the circuit into smaller parts and find an equivalent resistance for each part.
Then continue this process until all of the parts are added together correctly
either in series or parallel until a single equivalent resistance is found.
c) All together all of the resistors in series, ignoring any wired in parallel as they do
not significantly add to the equivalent resistance of the circuit. The sum of the
resistors in series is the equivalent resistance.
d) All together all of the resistors in parallel, ignoring any wired in series as they do
not significantly add to the equivalent resistance of the circuit. The sum of the
resistors in parallel is the equivalent resistance.
27.7.7. Which one of the following choices is not one of Kirchoff’s
rules?
a) junction rule
b) emf rule
c) loop rule
d) slide rule
e) resistance rule
27.7.7. Which one of the following choices is not one of Kirchoff’s
rules?
a) junction rule
b) emf rule
c) loop rule
d) slide rule
e) resistance rule
27.7.8. Complete the following statement: The sum of the magnitudes
of the currents directed into a junction
a) equals the sum of the magnitudes of the currents directed out of the
junction.
b) is less than the total current directed out of the junction.
c) equals the current that is directed along one of the lines out of the
junction.
d) is divided equally among the number of lines directed out of the
junction.
e) is greater than the total current directed out of the junction.
27.7.8. Complete the following statement: The sum of the magnitudes
of the currents directed into a junction
a) equals the sum of the magnitudes of the currents directed out of the
junction.
b) is less than the total current directed out of the junction.
c) equals the current that is directed along one of the lines out of the
junction.
d) is divided equally among the number of lines directed out of the
junction.
e) is greater than the total current directed out of the junction.
10/25/2018
8
27.8.1. Which of the following devices is placed into a circuit to
measure the current that passes through it?
a) ammeter
b) gaussmeter
c) voltmeter
d) diffractometer
e) flowmeter
27.8.1. Which of the following devices is placed into a circuit to
measure the current that passes through it?
a) ammeter
b) gaussmeter
c) voltmeter
d) diffractometer
e) flowmeter
27.8.2. Which one of the following statements is not a characteristic of
a voltmeter?
a) The voltmeter measures the voltage between two points in a circuit.
b) The voltmeter is designed to measure nearly the same voltage that
is present when the meter is not connected.
c) The voltmeter is not placed directly into a circuit.
d) The voltmeter is designed to draw very little current from the
circuit being measured.
e) An ideal voltmeter has almost no resistance.
27.8.2. Which one of the following statements is not a characteristic of
a voltmeter?
a) The voltmeter measures the voltage between two points in a circuit.
b) The voltmeter is designed to measure nearly the same voltage that
is present when the meter is not connected.
c) The voltmeter is not placed directly into a circuit.
d) The voltmeter is designed to draw very little current from the
circuit being measured.
e) An ideal voltmeter has almost no resistance.
27.9.1. When does a charging capacitor stop charging?
a) when the amount of charge on the two plates is equal
b) when the potential difference across the plates of the capacitor is
equal to zero volts
c) when the amount of charge on the two plates is infinitely large
d) when the potential difference across the plates of the capacitor is
equal to the emf of the battery
e) when all of the charge available in the circuit has been forced to
collect on the plates of the capacitor
27.9.1. When does a charging capacitor stop charging?
a) when the amount of charge on the two plates is equal
b) when the potential difference across the plates of the capacitor is
equal to zero volts
c) when the amount of charge on the two plates is infinitely large
d) when the potential difference across the plates of the capacitor is
equal to the emf of the battery
e) when all of the charge available in the circuit has been forced to
collect on the plates of the capacitor
10/25/2018
9
27.9.2. What effect, if any, does increasing the resistance in an RC circuit have
on the charging of the capacitor?
a) The resistance has no effect on the charging of the capacitor, which is
determined by the emf of the battery and the capacitance of the capacitor.
b) Increasing the resistance causes the charging time to increase since the rate at
which charges are moving to the capacitor increases.
c) The charging time will decrease as the resistance is increased because the
rate at which charges are moving to the capacitor decreases.
d) Increasing the resistance increases the charging time since the emf of the
battery will be reduced.
e) Increasing the resistance decreases the charging time since the emf of the
battery will be reduced.
27.9.2. What effect, if any, does increasing the resistance in an RC circuit have
on the charging of the capacitor?
a) The resistance has no effect on the charging of the capacitor, which is
determined by the emf of the battery and the capacitance of the capacitor.
b) Increasing the resistance causes the charging time to increase since the rate at
which charges are moving to the capacitor increases.
c) The charging time will decrease as the resistance is increased because the
rate at which charges are moving to the capacitor decreases.
d) Increasing the resistance increases the charging time since the emf of the
battery will be reduced.
e) Increasing the resistance decreases the charging time since the emf of the
battery will be reduced.
27.9.3. What effect, if any, does increasing the capacitance in an RC circuit have
on the charging of the capacitor?
a) The capacitance has no effect on the charging of the capacitor, which is
determined by the emf of the battery and the circuit resistance.
b) Increasing the capacitance causes the charging time to increase since the rate
at which charges are moving to the capacitor increases.
c) The charging time will decrease as the capacitance is increased because the
rate at which charges are moving to the capacitor decreases.
d) Increasing the capacitance increases the charging time since the capacitor can
hold more charge.
e) Increasing the capacitance decreases the charging time since the emf of the
battery will be reduced.
27.9.3. What effect, if any, does increasing the capacitance in an RC circuit have
on the charging of the capacitor?
a) The capacitance has no effect on the charging of the capacitor, which is
determined by the emf of the battery and the circuit resistance.
b) Increasing the capacitance causes the charging time to increase since the rate
at which charges are moving to the capacitor increases.
c) The charging time will decrease as the capacitance is increased because the
rate at which charges are moving to the capacitor decreases.
d) Increasing the capacitance increases the charging time since the capacitor can
hold more charge.
e) Increasing the capacitance decreases the charging time since the emf of the
battery will be reduced.
27.9.4. Which of the following quantities is equal to the time constant
for a charging capacitor?
a) the time it takes a capacitor to reach 33 % of its maximum charge
b) the time it takes a capacitor to reach 50 % of its maximum charge
c) the time it takes a capacitor to reach 66 % of its maximum charge
d) the time it takes a capacitor to reach 75 % of its maximum charge
e) the time it takes a capacitor to reach its maximum charge
27.9.4. Which of the following quantities is equal to the time constant
for a charging capacitor?
a) the time it takes a capacitor to reach 33 % of its maximum charge
b) the time it takes a capacitor to reach 50 % of its maximum charge
c) the time it takes a capacitor to reach 66 % of its maximum charge
d) the time it takes a capacitor to reach 75 % of its maximum charge
e) the time it takes a capacitor to reach its maximum charge
10/25/2018
10
27.9.5. Consider each of the graphs shown. Which of these graphs
represents the charge on a capacitor as it is being charged in a
circuit containing a resistor and a capacitor in series shortly after
they are connected to a battery?
a) A
b) B
c) C
d) D
e) E
27.9.5. Consider each of the graphs shown. Which of these graphs
represents the charge on a capacitor as it is being charged in a
circuit containing a resistor and a capacitor in series shortly after
they are connected to a battery?
a) A
b) B
c) C
d) D
e) E
27.9.6. A circuit contains a capacitor with a capacitance C and a
resistor with a resistance R connected in series with a battery.
Which one of the following mathematical expressions correctly
represents the time constant for this circuit?
a)
b)
c)
d)
e)
2
21 RC=
C
R=
RC=
RC21=
R
C=
27.9.6. A circuit contains a capacitor with a capacitance C and a
resistor with a resistance R connected in series with a battery.
Which one of the following mathematical expressions correctly
represents the time constant for this circuit?
a)
b)
c)
d)
e)
2
21 RC=
C
R=
RC=
RC21=
R
C=
10/25/2018
1
Halliday/Resnick/Walker
Fundamentals of Physics
Classroom Response System Questions
Chapter 27 Circuits
Interactive Lecture Questions
27.3.1. In physics lab, two students measured the potential difference
between the terminals of a battery and the current in a circuit connected
to the battery. The students then made a graph of the two parameters as
shown. They then drew a best fit line through the data. From their
results, determine the approximate internal resistance of the battery.
a) 0.002
b) 0.08
c) 0.1
d) 0.3
e) 0.6
27.3.1. In physics lab, two students measured the potential difference
between the terminals of a battery and the current in a circuit connected
to the battery. The students then made a graph of the two parameters as
shown. They then drew a best fit line through the data. From their
results, determine the approximate internal resistance of the battery.
a) 0.002
b) 0.08
c) 0.1
d) 0.3
e) 0.6
27.3.2. A non-ideal battery has a 6.0-V emf and an internal resistance
of 0.6 . Determine the terminal voltage when the current drawn
from the battery is 1.0 A.
a) 5.0 V
b) 6.0 V
c) 5.4 V
d) 6.6 V
e) 5.8 V
27.3.2. A non-ideal battery has a 6.0-V emf and an internal resistance
of 0.6 . Determine the terminal voltage when the current drawn
from the battery is 1.0 A.
a) 5.0 V
b) 6.0 V
c) 5.4 V
d) 6.6 V
e) 5.8 V
10/25/2018
2
27.4.1. Consider a circuit that contains an ideal battery and a resistor to form
a complete circuit. Which one of the following statements concerning
the work done by the battery is true?
a) No work is done by the battery in such a circuit.
b) The work done is equal to the thermal energy dissipated by the resistor.
c) The work done is equal to the work needed to move a single charge from
one side of the battery to the other.
d) The work done is equal to the emf of the battery.
e) The work done is equal to the product of the current flowing through the
circuit and the resistor.
27.4.1. Consider a circuit that contains an ideal battery and a resistor to form
a complete circuit. Which one of the following statements concerning
the work done by the battery is true?
a) No work is done by the battery in such a circuit.
b) The work done is equal to the thermal energy dissipated by the resistor.
c) The work done is equal to the work needed to move a single charge from
one side of the battery to the other.
d) The work done is equal to the emf of the battery.
e) The work done is equal to the product of the current flowing through the
circuit and the resistor.
27.5.1. Two 20- resistors are connected in series. A potential
difference of 9 V is then applied across the resistors. What is the
resulting current through the resistors?
a) 0.23 A
b) 0.45 A
c) 0.90 A
d) 2.2 A
e) 4.4 A
27.5.1. Two 20- resistors are connected in series. A potential
difference of 9 V is then applied across the resistors. What is the
resulting current through the resistors?
a) 0.23 A
b) 0.45 A
c) 0.90 A
d) 2.2 A
e) 4.4 A
27.5.2. Consider the circuit shown in the drawing. Two identical light bulbs, labeled
A and B, are connected in series with a battery and are illuminated equally.
There is a switch in the circuit that is initially open. Which one of the following
statements concerning the two bulbs is true after the switch is closed?
a) Bulbs A and B will be off.
b) Bulbs A and B will be equally
illuminated.
c) Bulb A will be brighter and bulb B
will be off.
d) Bulb A will be off and bulb B will be
brighter.
e) Both bulbs will be dimmer than before the switch was closed.
27.5.2. Consider the circuit shown in the drawing. Two identical light bulbs, labeled
A and B, are connected in series with a battery and are illuminated equally.
There is a switch in the circuit that is initially open. Which one of the following
statements concerning the two bulbs is true after the switch is closed?
a) Bulbs A and B will be off.
b) Bulbs A and B will be equally
illuminated.
c) Bulb A will be brighter and bulb B
will be off.
d) Bulb A will be off and bulb B will be
brighter.
e) Both bulbs will be dimmer than before the switch was closed.
10/25/2018
3
27.5.3. Consider the three resistors and the battery in the circuit
shown. Which resistors, if any, are connected in series?
a) R1 and R2
b) R1 and R3
c) R2 and R3
d) R1 and R2 and R3
e) No resistors are connected in series.
27.5.3. Consider the three resistors and the battery in the circuit
shown. Which resistors, if any, are connected in series?
a) R1 and R2
b) R1 and R3
c) R2 and R3
d) R1 and R2 and R3
e) No resistors are connected in series.
27.5.4. Consider the circuit shown. If the ideal emf in the circuit is 24
V and the three resistances are R1 = 2.5 , R2 = 4.0 , and R3 =
6.0 , determine the current in the 4.0 resistor.
a) 1.2 A
b) 1.9 A
c) 4.0 A
d) 6.0 A
e) 6.5 A
27.5.4. Consider the circuit shown. If the ideal emf in the circuit is 24
V and the three resistances are R1 = 2.5 , R2 = 4.0 , and R3 =
6.0 , determine the current in the 4.0 resistor.
a) 1.2 A
b) 1.9 A
c) 4.0 A
d) 6.0 A
e) 6.5 A
27.7.1 Two 20- resistors are connected in parallel. A potential
difference of 9 V is then applied across both resistors. What is the
resulting total current through the two resistors?
a) 0.23 A
b) 0.45 A
c) 0.90 A
d) 2.2 A
e) 4.4 A
27.7.1 Two 20- resistors are connected in parallel. A potential
difference of 9 V is then applied across both resistors. What is the
resulting total current through the two resistors?
a) 0.23 A
b) 0.45 A
c) 0.90 A
d) 2.2 A
e) 4.4 A
10/25/2018
4
27.7.2. Consider the three resistors and the battery in the circuit
shown. Which resistors, if any, are connected in parallel?
a) R1 and R2
b) R1 and R3
c) R2 and R3
d) R1 and R2 and R3
e) No resistors are connected in parallel.
27.7.2. Consider the three resistors and the battery in the circuit
shown. Which resistors, if any, are connected in parallel?
a) R1 and R2
b) R1 and R3
c) R2 and R3
d) R1 and R2 and R3
e) No resistors are connected in parallel.
27.7.3. Consider the circuits shown in parts A and B in the picture. In part A, a light
bulb is plugged into a wall outlet that has a voltage of 120 volts. A current i
passes through the circuit and the bulb turns on. In part B, a second, identical
light bulb is connected in parallel in the circuit. How does the total current in
circuit B compare with that in circuit A?
a) The current is the same, i, as in part A.
b) The current is twice as much, 2i,
as in part A.
c) The current in part B is zero amperes.
d) The current is one fourth as much,
0.25i, as in part A.
e) The current is one half as much, 0.5i, as in part A.
27.7.3. Consider the circuits shown in parts A and B in the picture. In part A, a light
bulb is plugged into a wall outlet that has a voltage of 120 volts. A current i
passes through the circuit and the bulb turns on. In part B, a second, identical
light bulb is connected in parallel in the circuit. How does the total current in
circuit B compare with that in circuit A?
a) The current is the same, i, as in part A.
b) The current is twice as much, 2i,
as in part A.
c) The current in part B is zero amperes.
d) The current is one fourth as much,
0.25i, as in part A.
e) The current is one half as much, 0.5i, as in part A.
27.7.4. Two light bulbs, one “50 W” bulb and one “100 W” bulb, are
connected in parallel with a standard 120 volt ac electrical outlet.
The brightness of a light bulb is directly related to the power it
dissipates. Therefore, the 100 W bulb appears brighter. How does
the brightness of the two bulbs compare when these same bulbs are
connected in series with the same outlet?
a) Both bulbs will be equally bright.
b) The “100 W” bulb will be brighter.
c) The “50 W” bulb will be brighter.
27.7.4. Two light bulbs, one “50 W” bulb and one “100 W” bulb, are
connected in parallel with a standard 120 volt ac electrical outlet.
The brightness of a light bulb is directly related to the power it
dissipates. Therefore, the 100 W bulb appears brighter. How does
the brightness of the two bulbs compare when these same bulbs are
connected in series with the same outlet?
a) Both bulbs will be equally bright.
b) The “100 W” bulb will be brighter.
c) The “50 W” bulb will be brighter.
10/25/2018
5
27.7.5. Consider the three identical light bulbs shown in the circuit. Bulbs B
and C are wired in series with each other and are wired in parallel with
bulb A. When the bulbs are connected to the battery as shown, how does
the brightness of each bulb compare to the others?
a) Bulbs B and C are equally bright,
but bulb A is less bright.
b) Bulbs B and C are equally bright,
but less bright than bulb A.
c) All three bulbs are equally bright.
d) Bulbs A and B are equally bright, but bulb C is less bright.
e) Only bulb A is illuminated.
27.7.5. Consider the three identical light bulbs shown in the circuit. Bulbs B
and C are wired in series with each other and are wired in parallel with
bulb A. When the bulbs are connected to the battery as shown, how does
the brightness of each bulb compare to the others?
a) Bulbs B and C are equally bright,
but bulb A is less bright.
b) Bulbs B and C are equally bright,
but less bright than bulb A.
c) All three bulbs are equally bright.
d) Bulbs A and B are equally bright, but bulb C is less bright.
e) Only bulb A is illuminated.
27.7.6. A circuit is formed using a battery, three identical resistors, and
connecting wires as shown. How does the current passing through
R3 compare with that passing through R1?
a) I3 < I1
b) I3 = I1
c) I3 > I1
d) This cannot be determined without knowing the amount of current
passing through R2.
27.7.6. A circuit is formed using a battery, three identical resistors, and
connecting wires as shown. How does the current passing through
R3 compare with that passing through R1?
a) I3 < I1
b) I3 = I1
c) I3 > I1
d) This cannot be determined without knowing the amount of current
passing through R2.
27.7.7. What is the approximate equivalent resistance of the five
resistors shown in the circuit?
a) 21
b) 7
c) 11
d) 14
e) 19
27.7.7. What is the approximate equivalent resistance of the five
resistors shown in the circuit?
a) 21
b) 7
c) 11
d) 14
e) 19
10/25/2018
6
27.7.8. What is the current through the 4- resistor in this circuit?
a) 1.27 A
b) 1.75 A
c) 2.0 A
d) 3.3 A
e) 4.5 A
27.7.8. What is the current through the 4- resistor in this circuit?
a) 1.27 A
b) 1.75 A
c) 2.0 A
d) 3.3 A
e) 4.5 A
27.7.9. What is the current through the 1- resistor in this circuit?
a) 2.8 A
b) 3.0 A
c) 3.4 A
d) 4.3 A
e) 4.8 A
27.7.9. What is the current through the 1- resistor in this circuit?
a) 2.8 A
b) 3.0 A
c) 3.4 A
d) 4.3 A
e) 4.8 A
27.7.10. Which one of the following equations is not correct relative
to the other four equations determined by applying Kirchoff’s
Rules to the circuit shown?
a) I2 = I1 + I4
b) I2 = I3 + I5
c) 6 V − (8 ) I1 − (5 ) I2 − (4 ) I3 = 0
d) 6 V − (6 ) I4 − (5 ) I2 − (2 ) I5 = 0
e) 6 V − (8 ) I1 − (6 ) I4 − 6 V − (2 ) I5 − (4 ) I3 = 0
27.7.10. Which one of the following equations is not correct relative
to the other four equations determined by applying Kirchoff’s
Rules to the circuit shown?
a) I2 = I1 + I4
b) I2 = I3 + I5
c) 6 V − (8 ) I1 − (5 ) I2 − (4 ) I3 = 0
d) 6 V − (6 ) I4 − (5 ) I2 − (2 ) I5 = 0
e) 6 V − (8 ) I1 − (6 ) I4 − 6 V − (2 ) I5 − (4 ) I3 = 0
10/25/2018
7
27.7.11. Some light bulbs are connected in parallel to a 120 V source
as shown in the figure. Each bulb dissipates an average power of
60 W. The circuit has a fuse F that burns out when the current in
the circuit exceeds 9 A. Determine the largest number of bulbs,
which can be used in this circuit without burning out the fuse.
a) 9
b) 17
c) 25
d) 34
e) 36
27.7.11. Some light bulbs are connected in parallel to a 120 V source
as shown in the figure. Each bulb dissipates an average power of
60 W. The circuit has a fuse F that burns out when the current in
the circuit exceeds 9 A. Determine the largest number of bulbs,
which can be used in this circuit without burning out the fuse.
a) 9
b) 17
c) 25
d) 34
e) 36
27.9.1. What effect, if any, does increasing the battery emf in an RC circuit
have on the time to charge the capacitor?
a) The charging time will decrease because the rate of charge flowing to the
plates will increase.
b) The charging time will decrease because the rate of charge flowing to the
plates will decrease.
c) The charging time will not change because the charging time does not
depend on the battery emf.
d) The charging time will increase because the emf is increased.
e) The charging time will decrease because potential difference across the
plates will be larger.
27.9.1. What effect, if any, does increasing the battery emf in an RC circuit
have on the time to charge the capacitor?
a) The charging time will decrease because the rate of charge flowing to the
plates will increase.
b) The charging time will decrease because the rate of charge flowing to the
plates will decrease.
c) The charging time will not change because the charging time does not
depend on the battery emf.
d) The charging time will increase because the emf is increased.
e) The charging time will decrease because potential difference across the
plates will be larger.
27.9.2. The resistance in an RC circuit is comprised of a 1.5-M
resistor in parallel with a 2.0-M resistor. What is the time
constant for this circuit if the capacitance is 2.5 µF?
a) 2.0 s
b) 7.0 ms
c) 5.0 µs
d) 120 s
e) 4000 s
27.9.2. The resistance in an RC circuit is comprised of a 1.5-M
resistor in parallel with a 2.0-M resistor. What is the time
constant for this circuit if the capacitance is 2.5 µF?
a) 2.0 s
b) 7.0 ms
c) 5.0 µs
d) 120 s
e) 4000 s
10/25/2018
8
27.9.3. In physics lab, Rebecca measured the voltage across an unknown
capacitor in an RC circuit, every ten seconds after a switch in the circuit
that allows the capacitor to discharge is closed. The capacitor was
initially fully charged. Using the graph, estimate the time constant.
a) 7.5 s
b) 15 s
c) 30 s
d) 45 s
e) 60 s
27.9.3. In physics lab, Rebecca measured the voltage across an unknown
capacitor in an RC circuit, every ten seconds after a switch in the circuit
that allows the capacitor to discharge is closed. The capacitor was
initially fully charged. Using the graph, estimate the time constant.
a) 7.5 s
b) 15 s
c) 30 s
d) 45 s
e) 60 s
27.9.4. An RC circuit contains a battery, a switch, a resistor, and a capacitor
– all connected in series. Initially, the switch is open and the capacitor is
uncharged. Which one of the following statements correctly describes
the current in the circuit during the time the capacitor is charging?
a) The current is increasing with increasing time.
b) The current is constant with increasing time.
c) The current is decreasing with increasing time.
d) The current increases for the first half of the time until the capacitor is
fully discharged, and then decreases during the second half of the time.
e) The current can either increase or decrease with increasing time
depending on the value of the time constant.
27.9.4. An RC circuit contains a battery, a switch, a resistor, and a capacitor
– all connected in series. Initially, the switch is open and the capacitor is
uncharged. Which one of the following statements correctly describes
the current in the circuit during the time the capacitor is charging?
a) The current is increasing with increasing time.
b) The current is constant with increasing time.
c) The current is decreasing with increasing time.
d) The current increases for the first half of the time until the capacitor is
fully discharged, and then decreases during the second half of the time.
e) The current can either increase or decrease with increasing time
depending on the value of the time constant.
27.9.5. An uncharged 5.0-µF capacitor and a resistor are connected in
series to a 12-V battery and an open switch to form a simple RC
circuit. The switch is closed at t = 0 s. The time constant of the
circuit is 4.0 s. What is the charge on either plate of the capacitor
after one time constant has elapsed?
a) 7.4 × 10–5 C
b) 5.5 × 10–5 C
c) 1.2 × 10–5 C
d) 3.8 × 10–5 C
e) 2.2 × 10–5 C
27.9.5. An uncharged 5.0-µF capacitor and a resistor are connected in
series to a 12-V battery and an open switch to form a simple RC
circuit. The switch is closed at t = 0 s. The time constant of the
circuit is 4.0 s. What is the charge on either plate of the capacitor
after one time constant has elapsed?
a) 7.4 × 10–5 C
b) 5.5 × 10–5 C
c) 1.2 × 10–5 C
d) 3.8 × 10–5 C
e) 2.2 × 10–5 C