Question 1

Here is a loop equation: . What does this equation represent?

Accepted Answer

A)  a charging capacitor 
B)  a discharging capacitor 
C)  a capacitor that has been disconnected 
D)  a charging resistor 
E)  an oscillating circuit 
A)  a charging capacitor 
B)  a discharging capacitor 
C)  a capacitor that has been disconnected 
D)  a charging resistor 
E)  an oscillating circuit

Question 2

In the figure, voltmeter V1 reads 600 V, voltmeter V2 reads 580 V, and ammeter A reads 100 A. The power wasted in the transmission line connecting the power house to the consumer is:

Accepted Answer

A)  1 kW 
B)  2 kW 
C)  58 kW 
D)  59 kW 
E)  60 kW 
A)  1 kW 
B)  2 kW 
C)  58 kW 
D)  59 kW 
E)  60 kW

Question 3

Resistor 1 has twice the resistance of resistor 2. They are connected in parallel to a battery. The ratio of the thermal energy dissipation by 1 to that by 2 is:

Accepted Answer

A)  1:4 
B)  1:2 
C)  1:1 
D)  2:1 
E)  4:1 
A)  1:4 
B)  1:2 
C)  1:1 
D)  2:1 
E)  4:1

Question 4

When switch S is open, the ammeter in the circuit shown reads 2.0 A. When S is closed, the ammeter reading:

Accepted Answer

A)  increases slightly 
B)  remains the same 
C)  decreases slightly 
D)  doubles 
E)  halves 
A)  increases slightly 
B)  remains the same 
C)  decreases slightly 
D)  doubles 
E)  halves

Question 5

A battery of emf 24 V is connected to a 6.0- $\Omega$ resistor. As a result, current of 3.0 A exists in the resistor. The rate at which energy is being dissipated in the battery is:

Accepted Answer

A)  3.0 W 
B)  6.0 W 
C)  18 W 
D)  54 W 
E)  72 W 
A)  3.0 W 
B)  6.0 W 
C)  18 W 
D)  54 W 
E)  72 W

Question 6

An ideal battery has an emf of 12 V. If it is connected to a circuit and creates a current of 4.0 A, what is the power?

Accepted Answer

A)  0.3 W 
B)  3.0 W 
C)  36 W 
D)  48 W 
E)  cannot tell without knowing the resistance of the circuit 
A)  0.3 W 
B)  3.0 W 
C)  36 W 
D)  48 W 
E)  cannot tell without knowing the resistance of the circuit

Question 7

A galvanometer has an internal resistance of 12  $\Omega$  and requires 0.01 A for full scale deflection. To convert it to a voltmeter reading 3 V full scale, one must use a series resistance of:

Accepted Answer

A)  102  $\Omega$ 
B)  288  $\Omega$ 
C)  300  $\Omega$ 
D)  360  $\Omega$ 
E)  412  $\Omega$ 
A)  102  $\Omega$ 
B)  288  $\Omega$ 
C)  300  $\Omega$ 
D)  360  $\Omega$ 
E)  412  $\Omega$

Question 8

In the diagrams, all light bulbs are identical and all emf devices are identical. In which circuit (I, II, III, IV, V) will the bulbs be dimmest?

Accepted Answer

A)  I 
B)  II 
C)  III 
D)  IV 
E)  V 
A)  I 
B)  II 
C)  III 
D)  IV 
E)  V

Question 9

If a circuit has L closed loops, B branches, and J junctions the number of independent loop equations is:

Accepted Answer

A)  B - J + 1 
B)  B - J 
C)  B 
D)  L 
E)  L - J 
A)  B - J + 1 
B)  B - J 
C)  B 
D)  L 
E)  L - J

Question 10

Resistances of 2.0  $\Omega$, 4.0  $\Omega$, and 6.0  $\Omega$ and a 24-V battery are all in series. The current in the 2.0  $\Omega$ resistor is:

Accepted Answer

A)  12 A 
B)  4.0 A 
C)  2.4 A 
D)  2.0 A 
E)  0.50 A 
A)  12 A 
B)  4.0 A 
C)  2.4 A 
D)  2.0 A 
E)  0.50 A

Question 11

Each of the resistors in the diagram is 12  $\Omega$. The resistance of the entire circuit is:

Accepted Answer

A)  5.8  $\Omega$ 
B)  25  $\Omega$ 
C)  48  $\Omega$ 
D)  120  $\Omega$ 
E)  none of these 
A)  5.8  $\Omega$ 
B)  25  $\Omega$ 
C)  48  $\Omega$ 
D)  120  $\Omega$ 
E)  none of these

Question 12

In the circuit shown, the capacitor is initially uncharged, and V = 10 V. At time t = 0, switch S is closed. If  $ \tau $denotes the time constant, the approximate current through the 3  $\Omega$  resistor when t =  $ \tau $/10 is:

Accepted Answer

A)  0.50 A 
B)  0.75 A 
C)  1.0 A 
D)  1.5 A 
E)  3.0 A 
A)  0.50 A 
B)  0.75 A 
C)  1.0 A 
D)  1.5 A 
E)  3.0 A

Question 13

A battery with an emf of 12 V and an internal resistance of 1  $\Omega$ is used to charge a battery with an emf of 10 V and an internal resistance of 1  $\Omega$. The current in the circuit is:

Accepted Answer

A)  1 A 
B)  2 A 
C)  4 A 
D)  11 A 
E)  22 A 
A)  1 A 
B)  2 A 
C)  4 A 
D)  11 A 
E)  22 A

Question 14

In the diagram R1 > R2 > R3. Rank the three resistors according to the current in them, least to greatest.

Accepted Answer

A)  1, 2, 3 
B)  3, 2, 1 
C)  1, 3, 2 
D)  3, 1, 2 
E)  All are the same 
A)  1, 2, 3 
B)  3, 2, 1 
C)  1, 3, 2 
D)  3, 1, 2 
E)  All are the same

Question 15

Resistances of 2.0  $\Omega$, 4.0  $\Omega$ and 6.0  $\Omega$ and a 24-V emf device are all in series. The potential difference across the 2.0- $\Omega$resistor is:

Accepted Answer

A)  4 V 
B)  8 V 
C)  12 V 
D)  24 V 
E)  48 V 
A)  4 V 
B)  8 V 
C)  12 V 
D)  24 V 
E)  48 V

Question 16

Resistances of 2.0  $\Omega$, 4.0  $\Omega$, and 6.0  $\Omega$ and a 24-V emf device are all in series. The circuit is initially ungrounded. After grounding, the current in the circuit:

Accepted Answer

A)  increases 
B)  decreases 
C)  does not change 
D)  depends on where in the circuit the ground wire is attached 
E)  depends on what the circuit is grounded to 
A)  increases 
B)  decreases 
C)  does not change 
D)  depends on where in the circuit the ground wire is attached 
E)  depends on what the circuit is grounded to

Question 17

In the circuit shown, both resistors have the same value R. Suppose switch S is initially closed and capacitor C is charged. When switch S is then opened, the circuit has a time constant  $ \tau $a. Conversely, suppose S is initially open and capacitor C is uncharged. When switch S is then closed, the circuit has a time constant  $ \tau $b. The ratio  $ \tau $a/ $ \tau $b is:

Accepted Answer

A)  0.5 
B)  0.67 
C)  1 
D)  1.5 
E)  2 
A)  0.5 
B)  0.67 
C)  1 
D)  1.5 
E)  2

Question 18

In an antique automobile, a 6-V battery supplies a total of 48 W to two identical headlights in parallel. The resistance of each bulb is:

Accepted Answer

A)  0.75 Ω 
B)  1.5 Ω 
C)  3 Ω 
D)  4 Ω 
E)  8 Ω 
A)  0.75 Ω 
B)  1.5 Ω 
C)  3 Ω 
D)  4 Ω 
E)  8 Ω

Question 19

A certain capacitor, in series with a resistor, is being charged. At the end of 10 ms its charge is half the final value. The time constant for the process is about:

Accepted Answer

A)  5.0 ms 
B)  6.9 ms 
C)  10 ms 
D)  14 ms 
E)  20 ms 
A)  5.0 ms 
B)  6.9 ms 
C)  10 ms 
D)  14 ms 
E)  20 ms

Question 20

A total resistance of 3.0 $ \omega $is to be produced by combining an unknown resistor R with a 12$ \omega $resistor. What is the value of R and how is it to be connected to the 12  $\Omega$resistor?

Accepted Answer

A)  2.4  $\Omega$, parallel 
B)  2.4 $\Omega$), series 
C)  4.0  $\Omega$, parallel 
D)  4.0  $\Omega$, series 
E)  9.0 $\Omega$ , series 
A)  2.4  $\Omega$, parallel 
B)  2.4 $\Omega$), series 
C)  4.0  $\Omega$, parallel 
D)  4.0  $\Omega$, series 
E)  9.0 $\Omega$ , series

Exam 27: Circuits

Here is a loop equation: . What does this equation represent?

In the figure, voltmeter V1 reads 600 V, voltmeter V2 reads 580 V, and ammeter A reads 100 A. The power wasted in the transmission line connecting the power house to the consumer is:

Resistor 1 has twice the resistance of resistor 2. They are connected in parallel to a battery. The ratio of the thermal energy dissipation by 1 to that by 2 is:

When switch S is open, the ammeter in the circuit shown reads 2.0 A. When S is closed, the ammeter reading:

A battery of emf 24 V is connected to a 6.0- Ω\OmegaΩ resistor. As a result, current of 3.0 A exists in the resistor. The rate at which energy is being dissipated in the battery is:

An ideal battery has an emf of 12 V. If it is connected to a circuit and creates a current of 4.0 A, what is the power?

A galvanometer has an internal resistance of 12 Ω\OmegaΩ and requires 0.01 A for full scale deflection. To convert it to a voltmeter reading 3 V full scale, one must use a series resistance of:

In the diagrams, all light bulbs are identical and all emf devices are identical. In which circuit (I, II, III, IV, V) will the bulbs be dimmest?

If a circuit has L closed loops, B branches, and J junctions the number of independent loop equations is:

Resistances of 2.0 Ω\OmegaΩ , 4.0 Ω\OmegaΩ , and 6.0 Ω\OmegaΩ and a 24-V battery are all in series. The current in the 2.0 Ω\OmegaΩ resistor is:

Each of the resistors in the diagram is 12 Ω\OmegaΩ . The resistance of the entire circuit is:

In the circuit shown, the capacitor is initially uncharged, and V = 10 V. At time t = 0, switch S is closed. If τ \tau τ denotes the time constant, the approximate current through the 3 Ω\OmegaΩ resistor when t = τ \tau τ /10 is:

A battery with an emf of 12 V and an internal resistance of 1 Ω\OmegaΩ is used to charge a battery with an emf of 10 V and an internal resistance of 1 Ω\OmegaΩ . The current in the circuit is:

In the diagram R1 > R2 > R3. Rank the three resistors according to the current in them, least to greatest.

Resistances of 2.0 Ω\OmegaΩ , 4.0 Ω\OmegaΩ and 6.0 Ω\OmegaΩ and a 24-V emf device are all in series. The potential difference across the 2.0- Ω\OmegaΩ resistor is:

Resistances of 2.0 Ω\OmegaΩ , 4.0 Ω\OmegaΩ , and 6.0 Ω\OmegaΩ and a 24-V emf device are all in series. The circuit is initially ungrounded. After grounding, the current in the circuit:

In an antique automobile, a 6-V battery supplies a total of 48 W to two identical headlights in parallel. The resistance of each bulb is:

A certain capacitor, in series with a resistor, is being charged. At the end of 10 ms its charge is half the final value. The time constant for the process is about:

A total resistance of 3.0 ω \omega ω is to be produced by combining an unknown resistor R with a 12 ω \omega ω resistor. What is the value of R and how is it to be connected to the 12 Ω\OmegaΩ resistor?

Measurement

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Vector

Motion in Two and Three Dimensions

Force and Motion I

Force and Motion II

Kinetic Energy and Work

Potential Energy and Conservation of Energy

Center of Mass and Linear Momentum

Rotation

Rolling, Torque, and Angular Momentum

Equilibrium and Elasticity

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The Kinetic Theory of Gases

Entropy and the Second Law of Thermodynamics

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Induction and Inductance

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Maxwells Equations; Magnetism of Matter

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Relativity

Photons and Matter Waves

More About Matter Waves

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Nuclear Physics

Energy From the Nucleus

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Filters

In the figure, voltmeter V₁ reads 600 V, voltmeter V₂ reads 580 V, and ammeter A reads 100 A. The power wasted in the transmission line connecting the power house to the consumer is:

A battery of emf 24 V is connected to a 6.0- $\Omega$ resistor. As a result, current of 3.0 A exists in the resistor. The rate at which energy is being dissipated in the battery is:

A galvanometer has an internal resistance of 12 $\Omega$ and requires 0.01 A for full scale deflection. To convert it to a voltmeter reading 3 V full scale, one must use a series resistance of:

Resistances of 2.0 $\Omega$ , 4.0 $\Omega$ , and 6.0 $\Omega$ and a 24-V battery are all in series. The current in the 2.0 $\Omega$ resistor is:

Each of the resistors in the diagram is 12 $\Omega$ . The resistance of the entire circuit is: $Each of the resistors in the diagram is 12 \Omega . The resistance of the entire circuit is:$

A battery with an emf of 12 V and an internal resistance of 1 $\Omega$ is used to charge a battery with an emf of 10 V and an internal resistance of 1 $\Omega$ . The current in the circuit is:

In the diagram R₁ > R₂ > R₃. Rank the three resistors according to the current in them, least to greatest.

Resistances of 2.0 $\Omega$ , 4.0 $\Omega$ and 6.0 $\Omega$ and a 24-V emf device are all in series. The potential difference across the 2.0- $\Omega$ resistor is:

Resistances of 2.0 $\Omega$ , 4.0 $\Omega$ , and 6.0 $\Omega$ and a 24-V emf device are all in series. The circuit is initially ungrounded. After grounding, the current in the circuit:

A total resistance of 3.0 $\omega$ is to be produced by combining an unknown resistor R with a 12 $\omega$ resistor. What is the value of R and how is it to be connected to the 12 $\Omega$ resistor?