# Quiz 26: Ac Electricity

Physics & Astronomy

Q 1Q 1

A transformer is a device used to
A)transform an alternating current into a direct current.
B)transform a direct current into an alternating current.
C)increase or decrease an ac voltage.
D)increase or decrease a dc voltage.

Free

Multiple Choice

C

Q 2Q 2

A transformer is a device that normally
A)operates on either dc or ac.
B)operates only on ac.
C)operates only on dc.

Free

Multiple Choice

B

Q 3Q 3

If the secondary coil of a transformer contains more loops than the primary coil, then it is a
A)step-up transformer.
B)step-down transformer.

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Multiple Choice

A

Q 4Q 4

If the primary coil of a transformer contains more loops than the secondary coil then it is a
A)step-up transformer.
B)step-down transformer.

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Multiple Choice

Q 5Q 5

An ideal solenoid has a self-inductance L. If you now double its radius and its length, but do not change the number of coils, what will its self-inductance be?
A)4L
B)2L
C)L
D)L/2
E)L/4

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Multiple Choice

Q 6Q 6

A resistor and an inductor are connected in series to an ideal battery of constant terminal voltage. At the moment contact is made with the battery, the voltage across the resistor is
A)greater than the battery's terminal voltage.
B)equal to the battery's terminal voltage.
C)less than the battery's terminal voltage, but not zero.
D)zero.
E)equal to the voltage across the inductor.

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Multiple Choice

Q 7Q 7

A resistor and an inductor are connected in series to an ideal battery of constant terminal voltage. At the moment contact is made with the battery, the voltage across the inductor is
A)greater than the battery's terminal voltage.
B)equal to the battery's terminal voltage.
C)less than the battery's terminal voltage, but not zero.
D)zero.
E)equal to the voltage across the resistor.

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Multiple Choice

Q 8Q 8

A resistor and an inductor are connected in series to a battery. The time constant for the circuit represents the time required for the current to reach
A)25% of the maximum current.
B)37% of the maximum current.
C)63% of the maximum current.
D)75% of the maximum current.
E)100% of the maximum current.

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Multiple Choice

Q 9Q 9

A resistor and an inductor are connected in series to a battery. The battery is suddenly removed from the circuit and replaced by a wire to complete the circuit. The time constant for of the new circuit represents the time required for the current to decrease to
A)25% of the original value.
B)37% of the original value.
C)63% of the original value.
D)75% of the original value.
E)zero.

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Multiple Choice

Q 10Q 10

A simple ac circuit is composed of a capacitor connected across the terminals of an ac power source. If the frequency of the source is doubled, what happens to the reactance of the capacitor?
A)It increases by a factor of 4.
B)It increases by a factor of 2.
C)It increases by a factor of
D)It decreases by a factor of 2.
E)It decreases by a factor of 4.

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Multiple Choice

Q 11Q 11

Consider a capacitor connected across the ac source. As the capacitance is increased, the current through the capacitor will
A)increase.
B)remain constant.
C)decrease.

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Multiple Choice

Q 12Q 12

A pure capacitor is connected to an ac power supply. In this circuit, the current
A)leads the voltage by 90°.
B)lags the voltage by 90°.
C)lags the voltage by 180°.
D)is in phase with the voltage.
E)None of the given answers are correct.

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Multiple Choice

Q 13Q 13

A pure inductor is connected to an ac power supply. In this circuit, the current
A)leads the voltage by 90°.
B)is in phase with the voltage.
C)lags the voltage by 45°.
D)lags the voltage by 90°.
E)leads the voltage by 45°.

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Multiple Choice

Q 14Q 14

A simple ac circuit consists of an inductor connected across the terminals of an ac power source. If the frequency of the ac source is decreased by a factor of four, what happens to the reactance of the inductor?
A)It decreases by a factor of four.
B)It decreases by a factor of eight.
C)It increases by a factor of two.
D)It increases by a factor of four.
E)It increases by a factor of eight.

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Multiple Choice

Q 15Q 15

As the frequency of the ac voltage across an inductor approaches zero, the inductive reactance of that coil
A)approaches zero.
B)approaches one.
C)approaches infinity.
D)becomes negative.

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Multiple Choice

Q 16Q 16

What is the phase angle between the voltages of the inductor and capacitor in a RLC series circuit?
A)0°
B)45°
C)90°
D)180°
E)270°

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Multiple Choice

Q 17Q 17

Which of the following statements is true for a series RLC ac circuit in resonance? (There could be more than one correct choice).
A)The inductive reactance and the capacitive reactance are both equal to zero.
B)The inductive reactance is equal to the capacitive reactance.
C)The current in the circuit is a minimum.
D)The current in the circuit is a maximum.
E)The rms current is equal to the peak current.

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Multiple Choice

Q 18Q 18

In the figure, which of the phasor diagrams represents a series RLC circuit driven at resonance?
A)1
B)2
C)3
D)4
E)5

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Multiple Choice

Q 19Q 19

In an RLC ac circuit, the values of the inductance and capacitance are both doubled. As a result of this change, the resonance frequency of the circuit is
A)the same as before.
B)reduced to one-half the original value.
C)reduced to one-fourth the original value.
D)twice the original value.
E)four times the original value.

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Multiple Choice

Q 20Q 20

In a RLC circuit, the values of the inductance and capacitance are both halved. As a result of this change, the resonance frequency of the circuit is
A)the same as before.
B)reduced to one-half the original value.
C)reduced to one-fourth the original value.
D)twice the original value.
E)four times the original value.

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Multiple Choice

Q 21Q 21

The primary coil of an ideal transformer has 100 turns and its secondary coil has 400 turns. If the ac voltage applied to the primary coil is 120 V, what voltage is present in its secondary coil?
A)100 V
B)30 V
C)70 V
D)480 V
E)400 V

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Multiple Choice

Q 22Q 22

An ideal transformer has 60 turns on its primary coil and 300 turns on its secondary coil. If 120 V at 2.0 A is applied to the primary,
(a)what voltage is present in the secondary?
(b)what current is present in the secondary?

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Essay

Q 23Q 23

An ideal step-up transformer doubles a primary voltage of 110 V. What is the ratio of the number of turns in its primary coil to the number of turns in the secondary coil?
A)1:4
B)4:1
C)2:1
D)1:2
E)1:8

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Multiple Choice

Q 24Q 24

When 5.0 A at 110 V flows in the primary of an ideal transformer, how many amps at 24 V can flow in the secondary?
A)1.1 A
B)4.6 A
C)5.0 A
D)23 A

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Multiple Choice

Q 25Q 25

The secondary coil of an ideal neon sign transformer provides 7500 V at 10.0 mA. The primary coil operates on 120 V. What current does the primary draw?
A)0.625 A
B)0.625 mA
C)0.160 A
D)1.66 A

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Multiple Choice

Q 26Q 26

The primary coil of an ideal transformer has 100 turns and its secondary coil has 400 turns. If the ac current in the secondary coil is 2 A, what is the current in its primary coil?
A)2 A
B)8 A
C)1/2 A
D)1/4 A
E)4 A

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Multiple Choice

Q 27Q 27

The primary coil of an ideal transformer has 600 turns and its secondary coil has 150 turns. If the current in the primary coil is 2 A, what is the current in its secondary coil?
A)8 A
B)1/2 A
C)1/4 A
D)2 A
E)4 A

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Multiple Choice

Q 28Q 28

A current of 2.0 A in the 100-turn primary of an ideal transformer causes 14 A to flow in the secondary. How many turns are in the secondary?
A)700
B)114
C)14
D)4

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Multiple Choice

Q 29Q 29

In an ideal transformer, how many turns are necessary in a 110-V primary if the 24-V secondary has 100 turns?
A)458
B)240
C)110
D)22

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Multiple Choice

Q 30Q 30

An ideal transformer consists of a 500-turn primary coil and a 2000-turn secondary coil. If the current in the secondary is 3.0 A, what is the current in the primary?
A)0.75 A
B)1.3 A
C)12 A
D)48 A

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Multiple Choice

Q 31Q 31

An ideal step-down transformer is needed to reduce a primary voltage of 120 V to 6.0 V. What must be the ratio of the number of turns in the secondary to the number of turns in the primary?

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Essay

Q 32Q 32

An ideal transformer steps down 120 V to 12. V and the 2630.-turn secondary supplies 12. A.
(a)Determine the current in the primary.
(b)Determine the turns ratio.
(c)What is the ratio of output power to input power?

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Essay

Q 33Q 33

An ideal transformer with 120 turns in its secondary supplies 12 V at 220 mA to a toy train. The primary is connected across a 120-V wall outlet.
(a)How many turns are in the primary?
(b)What is the primary current?
(c)What power is delivered by the wall outlet?

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Essay

Q 34Q 34

An ideal transformer has 60 turns on its primary coil and 300 turns on its secondary coil. If 120 V at 2.0 A is applied to the primary, what voltage and current are present in the secondary?

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Essay

Q 35Q 35

You need an ideal transformer to reduce a voltage of 150 V in the primary circuit to 25 V in the secondary circuit. The primary circuit has 130 windings and the secondary circuit is completed through a 55-Ω resistor. How many windings should the secondary circuit contain?

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Essay

Q 36Q 36

The primary of an ideal transformer has 100 turns and its secondary has 200 turns. If the input current at the primary is 100 A, we can expect the output current at the secondary to be
A)50 A.
B)100 A.
C)200 A.
D)none of the given answers.

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Multiple Choice

Q 37Q 37

The primary of an ideal transformer has 100 turns and its secondary has 200 turns. If the input voltage to the primary is 100 V, we can expect the output voltage of the secondary to be
A)50 V.
B)100 V.
C)200 V.
D)none of the given answers.

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Multiple Choice

Q 38Q 38

The primary of an ideal transformer has 100 turns and its secondary has 200 turns. Neglecting frictional losses, if the power input to the primary is 100 W, we can expect the power output of the secondary to be
A)50 W.
B)100 W.
C)200 W.
D)none of the given answers.

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Multiple Choice

Q 39Q 39

A generator produces 60 A of current at 120 V. The voltage is usually stepped up to 4500 V by an ideal transformer and transmitted through a power line of total resistance 1.0 Ω. Find the number of turns in the secondary if the primary has 200 turns.
A)5
B)200
C)4500
D)7500

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Multiple Choice

Q 40Q 40

What is the self-inductance of an ideal solenoid that is 300 cm long with a cross-sectional area of 1.00 × 10

^{-4}m^{2}and has 1000 turns of wire? (μ_{0}= 4π × 10^{-7}T ∙ m/A) A)4.19 nH B)4.19 pH C)4.19 μH D)41.9 nH E)41.9 µHFree

Multiple Choice

Q 41Q 41

A coil with a self-inductance of 6.0 H has a constant current of 2.0 A flowing through it for 2.0 s. What is the emf induced in this coil?
A)6.0 V
B)12 V
C)0.0 V
D)4.0 V
E)8.0 V

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Multiple Choice

Q 42Q 42

A coil with a self-inductance of 6.0 H is connected to a dc battery through a switch. As soon as the switch is closed, the rate of change of current is 2.0 A/s. What is the emf induced in this coil at this instant?
A)6.0 V
B)3.0 V
C)12 V
D)0.33 V
E)0.0 V

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Multiple Choice

Q 43Q 43

The inductance of a solenoid that is 16.0 cm long and has a cross-sectional area of 1.00 × is How many turns of wire does this solenoid have? (μ

_{0}= 4π × 10^{-7}T ∙ m/A) A)318,000 B)159,000 C)1130 D)282 E)150Free

Multiple Choice

Q 44Q 44

The figure shows a solenoid having no appreciable resistance. When the current in this solenoid is decreasing at a rate of 5.5 A/s, the self-induced emf in the solenoid is measured to be 9.5 V.
((a)What is the self-inductance of this solenoid?
(b)If the current is in the direction from b to a in the figure, which point, a or b, is at higher potential?

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Essay

Q 45Q 45

The current flowing through a circuit is changing at a rate of 6.0 A/s. If the circuit contains a 190-H inductor, what is the emf across the inductor?
A)1100 V
B)11 mV
C)32 mV
D)32 V

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Multiple Choice

Q 46Q 46

An ideal solenoid with 3000 turns is 70.0 cm long. If its self-inductance is 25.0 mH, what is its radius? (μ

_{0}= 4π × 10^{-7}T ∙ m/A) A)0.0222 m B)0.00199 m C)327 m D)52.0 mFree

Multiple Choice

Q 47Q 47

A simple series circuit consists of just a 3.4-µF capacitor and an 80-mH inductor, with no appreciable resistance. At t = 0 the capacitor has charge 5.4 µC and the current in the inductor is zero.
(a)How long after t = 0 will the current in the circuit be maximum?
(b)What will be this maximum current?

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Essay

Q 48Q 48

A simple circuit consists only of of a 1.0-μF capacitor and a 15-mH coil in series. At what frequency will this circuit oscillate?
A)15 kHz
B)1.3 kHz
C)0.77 kHz
D)67 Hz

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Multiple Choice

Q 49Q 49

What inductance is needed in series with a 4.7-μF capacitor so the circuit will oscillate at a frequency of 10 kHz?
A)21 μH
B)54 μH
C)4.7 mH
D)5.4 mH

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Multiple Choice

Q 50Q 50

What capacitance is needed in series with a 3.7-mH inductor so the circuit will oscillate at a frequency of 1000 Hz?
A)0.15 mF
B)15 μF
C)6.8 μF
D)0.015 μF

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Multiple Choice

Q 51Q 51

What size capacitor must be placed in series with a 40-mH coil so the circuit will oscillate with a frequency of 1000 Hz?
A)0.63 μF
B)0.50 μF
C)0.22 μF
D)0.17 μF

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Multiple Choice

Q 52Q 52

A series circuit contains an 80-μF capacitor, a 0.020-H inductor, and a switch. The resistance of the circuit is negligible. Initially, the switch is open, the capacitor voltage is 50 V, and the current in the inductor is zero. At time t = 0 s, the switch is closed. How long after closing the switch does the magnetic energy in the inductor first reach its maximum value?
A)2.0 ms
B)4.0 ms
C)6.0 ms
D)8.0 ms
E)10 ms

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Multiple Choice

Q 53Q 53

A series circuit contains an 80-μF capacitor, a 0.020-H inductor, and a switch. The resistance of the circuit is negligible. Initially, the switch is open, the capacitor voltage is 50 V, and the current in the inductor is zero. At time t = 0 s, the switch is closed. What is the maximum current in the circuit?
A)2.2 A
B)2.4 A
C)2.8 A
D)3.0 A
E)3.2 A

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Multiple Choice

Q 54Q 54

A series circuit contains an 80-μF capacitor, a 0.020-H inductor, and a switch. The resistance of the circuit is negligible. Initially, the switch is open, the capacitor voltage is 50 V, and the current in the inductor is zero. At time t = 0 s, the switch is closed. When the current in the circuit is 1.5 A, what is the charge on the capacitor?
A)2000 µC
B)2500 µC
C)3000 µC
D)3500 µC
E)4000 µC

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Multiple Choice

Q 55Q 55

A series circuit contains an 80-μF capacitor, a 0.020-H inductor, and a switch. The resistance of the circuit is negligible. Initially, the switch is open, the capacitor voltage is 50 V, and the current in the inductor is zero. At time t = 0 s, the switch is closed. When the potential across the capacitor is 30 V, what is the rate of change of the current?
A)1000 A/s
B)1500 A/s
C)2000 A/s
D)2500 A/s
E)3000 A/s

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Multiple Choice

Q 56Q 56

American power plants usually supply 120 V ac.
(a)At what frequency is this voltage supplied?
(b)What is the maximum voltage?

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Essay

Q 57Q 57

A 100-W light bulb is powered by 120 V ac 60.0-Hz household connection. Determine the rms current and the current amplitude.

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Essay

Q 58Q 58

The peak current and voltage outputs of a generator are 20 A and 240 V, respectively. What average power is provided by the generator?

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Essay

Q 59Q 59

The potential applied to a 20-Ω resistor is v = (60 V)cos(33t). What is the rms current through this resistor?

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Essay

Q 60Q 60

The current through a 50-Ω resistor is I = (0.80
A)sin(240t). What are (a)the current amplitude and (b)the rms current?

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Essay

Q 61Q 61

A 0.150-kW lamp is plugged into a 120-V ac wall outlet. What are (a)the peak current through the lamp, (b)the rms current through the lamp, and (c)the resistance of the lamp?

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Essay

Q 62Q 62

The potential applied to a 20-Ω resistor is (60 V)cos(33t). What is the average power consumed in the resistor?

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Essay

Q 63Q 63

If the maximum voltage of an ac signal is 8.0 V, what is the rms value of this voltage?
A)2.8 V
B)5.7 V
C)6.2 V
D)4.0 V
E)16.0 V

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Multiple Choice

Q 64Q 64

A 120-V rms voltage at 60.0 Hz is applied across an inductor, capacitor and a 100-Ω resistor in series. If the maximum value of the current in this circuit is 1.60 A, what is the rms value of the current in this circuit?
A)1.13 A
B)2.26 A
C)1.82 A
D)1.60 A
E)2.66 A

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Multiple Choice

Q 65Q 65

An alternating current is supplied to an electronic component with a rating that the voltage across it can never, even for an instant, exceed What is the highest rms voltage that can be supplied to this component while staying below the voltage limit?
A)8 V
B)16 V
C)256 V
D)8 V

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Multiple Choice

Q 66Q 66

What is the peak voltage in an ac circuit where the rms voltage is 120 V?
A)84.8 V
B)120 V
C)170 V
D)240 V

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Multiple Choice

Q 67Q 67

A 150-W lamp is placed into a 120-V ac outlet. What is the peak current?
A)0.80 A
B)0.88 A
C)1.2 A
D)1.8 A

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Multiple Choice

Q 68Q 68

A 10-Ω resistor is connected to a 120-V ac power supply. What is the peak current through the resistor?
A)12 A
B)17 A
C)0.083 A
D)0.12 A

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Multiple Choice

Q 69Q 69

The current through a 50-Ω resistor is I = (0.80
A)0.57 A
A)sin(240t), where t is measured in seconds. What is the rms current?
B)0.80 A
C)1.1 A
D)1.6 A

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Multiple Choice

Q 70Q 70

The current through a 50-Ω resistor is I = (0.80
A)16 W
A)sin(240t), where t is measured in seconds. How much power on average is dissipated in the resistor?
B)32 W
C)45 W
D)64 W

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Multiple Choice

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Essay

Q 72Q 72

At what frequency will the inductive reactance of a 44-mH inductor be equal to the capacitive reactance of a 27-pF capacitor?

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Essay

Q 73Q 73

A 0.10-μF capacitor is connected to a 120-V rms 60-Hz source.
(a)What is its capacitive reactance?
(b)What is the rms current to the capacitor?
(c)If both the capacitance and the frequency were doubled, what would be the rms current?

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Essay

Q 74Q 74

A 0.200-H inductor is connected to a 60.0-Hz 120-V rms source.
(a)What is the inductive reactance?
(b)What is the rms current to the inductor?
(c)If both the inductance and the frequency were doubled, what would be the rms current?

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Essay

Q 75Q 75

What capacitance will have the same reactance as a 100-mH inductance of both of them are in a 120-V 60-Hz circuit?

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Essay

Q 76Q 76

In the circuit shown in the figure, the 60-Hz ac source has a voltage amplitude of 120 V, the capacitive reactance is the inductive reactance is and the resistance is What is the capacitance C of the capacitor?
A)3.2 µF
B)6.3 µF
C)9.4 µF
D)13 µF
E)20 µF

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Multiple Choice

Q 77Q 77

The reactance of a capacitor is at a frequency of What is the capacitance?
A)0.066 μF
B)0.42 μF
C)2.6 μF
D)0.093 μF

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Multiple Choice

Q 78Q 78

A 6.0-μF capacitor is connected to an ac signal with a frequency of 60 Hz. If the maximum voltage applied to the capacitor is 8.0 V, what is its capacitive reactance?
A)6.0 Ω
B)440 Ω
C)7.5 × Ω
D)740 Ω
E)160 Ω

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Multiple Choice

Q 79Q 79

The capacitive reactance of a 44-μF capacitor in an ac circuit is 6.0 × Ω. What is the frequency of the applied signal?
A)80 Hz
B)17 Hz
C)800 Hz
D)6.0 Hz
E)2.2 Hz

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Multiple Choice

Q 80Q 80

A 120-V rms voltage is applied across a 6.0-μF capacitor. If the frequency of the generator is 60 Hz, what is the rms value of the current in the circuit?
A)0.47 A
B)0.37 A
C)0.071 A
D)0.17 A
E)0.27 A

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Multiple Choice

Q 81Q 81

At what frequency does a 10-μF capacitor have a reactance of 1200 Ω?
A)13 Hz
B)42 Hz
C)60 Hz
D)83 Hz

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Multiple Choice

Q 82Q 82

At what frequency will the capacitive reactance of a 0.010-μF capacitor be 100 Ω?
A)1.0 kHz
B)16 kHz
C)0.16 MHz
D)0.31 MHz

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Multiple Choice

Q 83Q 83

What is the rms current through a 0.0010-μF capacitor at 1000 Hz and 5.0 V?
A)5.4 μA
B)31 μA
C)3.1 mA
D)10 mA

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Multiple Choice

Q 84Q 84

What is the reactance of a 20-mH inductor at a frequency of 60 Hz?
A)7.5 Ω
B)0.13 Ω
C)1.2 Ω
D)1.2 mΩ
E)7.5 mΩ

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Multiple Choice

Q 85Q 85

At what frequency is the reactance of a 20.0-mH inductor equal to 120 Ω?
A)318 Hz
B)637 Hz
C)796 Hz
D)955 Hz
E)1110 Hz

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Multiple Choice

Q 86Q 86

In the circuit shown in the figure, the 60-Hz ac source has a voltage amplitude of 120 V, the capacitive reactance is the inductive reactance is and the resistance is What is the inductance L of the inductor?
A)770 mH
B)1700 mH
C)2900 mH
D)3700 mH
E)4800 mH

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Multiple Choice

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Multiple Choice

Q 88Q 88

What is the inductive reactance of a 2.50-mH coil at 1000 Hz?
A)2500 Ω
B)796 Ω
C)15.7 Ω
D)2.50 Ω

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Multiple Choice

Q 89Q 89

At what frequency will a 14.0-mH coil have 14.0 Ω of inductive reactance?
A)1000 Hz
B)505 Hz
C)257 Hz
D)159 Hz

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Multiple Choice

Q 90Q 90

The inductor in a radio receiver carries a current of amplitude 0.200 A when an ac voltage of amplitude 2.40 V is across it at a frequency of 1400 Hz. What is the value of the inductance?
A)1.43 mH
B)1.36 mH
C)9.20 mH
D)4.42 mH
E)1.97 mH

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Multiple Choice

Q 91Q 91

At what frequency will a 20.0-mH inductor have an inductive reactance of 100 Ω?
A)225 Hz
B)655 Hz
C)796 Hz
D)457 Hz
E)None of the other answers is correct.

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Multiple Choice

Q 92Q 92

What rms current flows in a 60-mH inductor when 120-V rms ac at a frequency of 20 kHz is applied to it?
A)8.0 mA
B)16 mA
C)24 mA
D)32 mA

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Multiple Choice

Q 93Q 93

What is the rms current through a 2.50-mH coil due to a 110-V rms, 60-Hz source?
A)0.94 A
B)2.5 A
C)104 A
D)117 A

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Multiple Choice

Q 94Q 94

A 120-V rms signal at 60.0 Hz is applied across a series combination of a 30.0-mH inductor and a resistor. If the rms value of the current in this circuit is 0.600 A, what is the resistance of the resistor?
A)80.0 Ω
B)268 Ω
C)143 Ω
D)200 Ω
E)30.0 Ω

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Multiple Choice

Q 95Q 95

A 120-V rms signal at 60 Hz is applied across a series combination of a 30-mH inductor and a 100-Ω resistor. What is the rms value of the current in this circuit?
A)0.80 A
B)1.2 A
C)1.4 A
D)1.6 A
E)1.8 A

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Multiple Choice

Q 96Q 96

A 120-V rms signal at 60 Hz is applied across a series combination of a 30-mH inductor and a 100-Ω resistor. What is the rms value of the voltage across the resistor?
A)120 V
B)60 V
C)100 V
D)150 V
E)0.70 V

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Multiple Choice

Q 97Q 97

A 120-V rms voltage is applied across a 6.0-μF capacitor and a series combination of a 100-Ω resistor. If the frequency of the power source is 60 Hz, what is the rms value of the current in the circuit?
A)0.26 A
B)0.36 A
C)0.46 A
D)0.56 A
E)0.76 A

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Multiple Choice

Q 98Q 98

A 120-V rms voltage at 60 Hz is applied across a series combination of a 20-μF capacitor and an unknown resistor. If the rms value of the current in the circuit is 0.60 A, what is the resistance of the resistor?
A)60 Ω
B)120 Ω
C)180 Ω
D)150 Ω
E)200 Ω

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Multiple Choice

Q 99Q 99

A 120-V rms signal at 60.0 Hz is applied across a series combination of a 30.0-mH inductor and a 100-Ω resistor. What is the rms value of the voltage across the inductor?
A)0.700 V
B)119 V
C)100 V
D)13.5 V
E)120 V

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Multiple Choice

Q 100Q 100

As shown in the figure, an ac source whose rms voltage is 80 V is in series with a 100-Ω resistor and a capacitor whose reactance is 200 Ω at the frequency of the source. What is the rms voltage across the capacitor?
A)66 V
B)68 V
C)70 V
D)72 V
E)74 V

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Multiple Choice

Q 101Q 101

A 120-V rms voltage at 2000 Hz is applied to a 6.0-mH inductor, a 2.0-μF capacitor, and a 200-Ω resistor. What is the rms value of the current in this circuit?
A)1.5 A
B)0.48 A
C)2.5 A
D)3.5 A
E)0.59 A

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Multiple Choice

Q 102Q 102

A 120-V rms voltage at 1000 Hz is applied to an inductor, a 2.00-μF capacitor and a 100-Ω resistor. If the rms value of the current in this circuit is 0.680 A, what is the inductance of the inductor?
A)34.2 mH
B)35.8 mH
C)11.4 mH
D)17.9 mH
E)22.8 mH

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Multiple Choice

Q 103Q 103

A 120-V rms voltage at 1.0 kHz is applied to a 2.0-mH inductor, a 4.0-μF capacitor and a resistor. If the rms value of the current in this circuit is 0.40 A, what is the value of the resistor?
A)300 Ω
B)95 Ω
C)420 Ω
D)120 Ω
E)240 Ω

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Multiple Choice

Q 104Q 104

A series circuit has a sinusoidal voltage supplied to it at with a peak voltage of It also contains a resistance, a capacitance, and a inductance. What is the peak current for this circuit?
A)6.3 μA
B)11 μA
C)26 μA
D)30 μA

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Multiple Choice

Q 105Q 105

In the circuit shown in the figure, the 60-Hz ac source has a voltage amplitude of 120 V, the capacitive reactance is the inductive reactance is and the resistance is What is the rms current in the circuit?
A)0.11 A
B)0.13 A
C)0.14 A
D)0.17 A
E)0.20 A

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Multiple Choice

Q 106Q 106

The figure shows a series ac circuit. The inductor has a reactance of 60 Ω and an inductance of 150 mH. A 50-Ω R and a capacitor C whose reactance is 90 Ω are also in the circuit, and the rms current in the circuit is 1.5 A. What is the rms voltage of the source?
A)87 V
B)84 V
C)81 V
D)78 V
E)75 V

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Multiple Choice

Q 107Q 107

The figure shows a series ac circuit. The inductor has a reactance of 80 Ω and an inductance of 220 mH. A 30-Ω resistor and a capacitor whose reactance is 80 Ω are also in the circuit, and the rms current in the circuit is 2.0 A. What is the capacitance of the capacitor?
A)34 μF
B)37 μF
C)32 μF
D)30 μF
E)27 μF

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Multiple Choice

Q 108Q 108

The figure shows a series ac circuit. The inductor has a reactance of 50 Ω and an inductance of 220 mH. An 80-Ω resistor and a capacitor whose reactance is 160 Ω are also in the circuit, and the rms current in the circuit is 2.2 A. What is the voltage amplitude across the capacitor?
A)500 V
B)350 V
C)630 V
D)770 V
E)210 V

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Multiple Choice

Q 109Q 109

A series circuit has a 50-Hz ac source, a 40-Ω resistor, a 0.70-H inductor, and a 60-μF capacitor, as shown in the figure. The rms current in the circuit is 1.6 A. What is the voltage amplitude of the source?
A)390 V
B)330 V
C)270 V
D)220 V
E)190 V

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Multiple Choice

Q 110Q 110

A series circuit has a 100-Ω resistor, a 0.100-μF capacitor, and a 2.00-mH inductor connected across a 120 V rms ac source operating at resonant frequency. What is the rms value of the voltage across the inductor?
A)170 V
B)150 V
C)120 V
D)54.0 V
E)533 V

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Multiple Choice

Q 111Q 111

A series circuit has a 100-Ω resistor, a 0.100-μF capacitor, and a 2.00-mH inductor connected across a 120-V rms ac source operating at resonant frequency. What is the rms value of the voltage across the capacitor?
A)54.0 V
B)120 V
C)150 V
D)533 V
E)170 V

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Multiple Choice

Q 112Q 112

A series circuit has a 100-Ω resistor, a 0.100-μF capacitor, and a 2.00-mH inductor connected across a 120-V rms ac source operating at 1000/π Hz. What is the rms voltage across the inductor?
A)120 mV
B)87.1 mV
C)302 mV
D)96.1 mV
E)200 mV

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Multiple Choice

Q 113Q 113

A series circuit consists of a 100-Ω resistor, a 10.0-μF capacitor, and a 0.350-H inductor. The circuit is connected to a 120-V rms, 60-Hz power supply. What is the rms current in the circuit?
A)0.42 A
B)0.52 A
C)0.62 A
D)0.72 A

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Multiple Choice

Q 114Q 114

A resistance of 55 Ω, a capacitor of capacitive reactance 30 Ω, and an inductor of inductive reactance 30 Ω are connected in series to a 110-V rms, 60-Hz power source. What rms current flows in this circuit?
A)2.0 A
B)less than 2.0 A
C)more than 2.0 A
D)none of the given answers

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Multiple Choice

Q 115Q 115

A resistance of 55 Ω, a capacitor of capacitive reactance 30 Ω, and an inductor of inductive reactance 30 Ω are connected in series to a 110-V rms 60-Hz power source. What rms current flows in this circuit?
A)more than 4.0 A
B)2.0 A
C)more than 2.0 A but less than 4.0 A
D)4.0 A
E)less than 2.0 A

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Multiple Choice

Q 116Q 116

A series circuit consists of a 0.440-H inductor, a 380.0-Ω resistor, a 5.70-μF capacitor, and an ac voltage source of amplitude Find the rms voltage across the capacitor when the circuit operates at resonance.

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Essay

Q 117Q 117

A 120-mH inductor is in series with a 20-Ω resistor and a variable capacitor that can range from 0.110 μF to 0.400 μF.
(a)What is the range of possible resonance frequencies?
(b)If the power supply is a 24-V rms source, what rms current flows at resonance?

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Essay

Q 118Q 118

What is the resonance frequency of a series ac circuit consisting of a 40.0 μF capacitor, a 55-Ω resistor, and a 0.030 H inductor?
A)0.15 kHz
B)0.9 kHz
C)6.9 kHz
D)6 kHz

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Multiple Choice

Q 119Q 119

A series ac circuit has a resonance frequency of 9.0 kHz. If the inductor in the circuit has a value of 2.0 H, and the resistance is 75 Ω, what is the capacitance of the circuit?
A)0.16 pF
B)156 pF
C)6.2 pF
D)17.7 pF

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Multiple Choice

Q 120Q 120

An ac circuit has a 100-Ω resistor in series with a 4.9-μF capacitor and a 700-mH inductor. At what frequency does the circuit act like a pure resistance?
A)0.29 MHz
B)1.9 MHz
C)12 MHz
D)0.54 kHz
E)86 Hz

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Multiple Choice

Q 121Q 121

A series RLC circuit has a 100-Ω resistor, a 0.100-μF capacitor and a 2.00-mH inductor connected across a 120-V rms ac voltage source operating at 1000/π Hz. What is the resonant frequency of this circuit?
A)70.7 kHz
B)17.9 kHz
C)22.5 kHz
D)35.3 kHz
E)11.3 kHz

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Multiple Choice

Q 122Q 122

What size capacitor should be placed in series with a 30-Ω resistor and a 40-mH inductive coil if the resonant frequency of the circuit is to be 1.0 kHz?
A)2.0 µF
B)0.63 µF
C)3.3 µF
D)6.0 µF
E)4.5 µF

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Multiple Choice