Question 1

For the circuit shown in the figure,what is the current through resistor R1?

Accepted Answer

A)  0.071 A 
B)  0.13 A 
C)  0.029 A 
D)  0.016 A 
A)  0.071 A 
B)  0.13 A 
C)  0.029 A 
D)  0.016 A A

Question 2

Consider the circuit shown in the figure.Note that two currents are shown.Calculate the emfs ε1 and ε3.

Accepted Answer

ε₁= 28 V ,ε₃ = 44 V

Question 3

Two identical resistors of resistance R = 24 Ω and a variable resistor Rx are connected to an ideal battery of voltage V as shown in the figure. What should be the value of the variable resistance Rx to make the voltage across the two parallel resistors equal to   .

Accepted Answer

A)  4.0 Ω 
B)  24 Ω 
C)  8.0 Ω 
D)  16 Ω 
E)  40 Ω 
A)  4.0 Ω 
B)  24 Ω 
C)  8.0 Ω 
D)  16 Ω 
E)  40 Ω C

Question 4

In the circuit shown in the figure,four identical resistors labeled A to D are connected to a battery as shown.S1 and S2 are switches.Which of the following actions would result in the GREATEST amount of current through resistor A?

Accepted Answer

A)  closing both switches 
B)  closing S1 only 
C)  closing S2 only 
D)  leaving both switches open as shown. 
A)  closing both switches 
B)  closing S1 only 
C)  closing S2 only 
D)  leaving both switches open as shown.

Question 5

A multiloop circuit is shown in the figure.Some circuit quantities are not labeled.It is not necessary to solve the entire circuit.The current I2 is closest to

Accepted Answer

A)  +0.1 A. 
B)  +0.3 A. 
C)  +0.5 A. 
D)  -0.1 A. 
E)  -0.3 A. 
A)  +0.1 A. 
B)  +0.3 A. 
C)  +0.5 A. 
D)  -0.1 A. 
E)  -0.3 A.

Question 6

When four identical resistors are connected to an ideal battery of voltage V = 10 V as shown in the figure,the current I is equal to 0.20 A.What is the value of the resistance R of the resistors?

Accepted Answer

A)  20 Ω 
B)  40 Ω 
C)  30 Ω 
D)  50 Ω 
E)  10 Ω 
A)  20 Ω 
B)  40 Ω 
C)  30 Ω 
D)  50 Ω 
E)  10 Ω

Question 7

The voltage and power ratings of a particular light bulb,which are its normal operating values,are 110 V and 60 W.Assume the resistance of the filament of the bulb is constant and is independent of operating conditions.If the light bulb is operated at a reduced voltage and the power drawn by the bulb is 36 W,what is the operating voltage of the bulb?

Accepted Answer

A)  66 V 
B)  72 V 
C)  78 V 
D)  85 V 
E)  90 V 
A)  66 V 
B)  72 V 
C)  78 V 
D)  85 V 
E)  90 V

Question 8

A resistor is made out of a long wire having a length L.Each end of the wire is attached to a terminal of a battery providing a constant voltage V0.A current I flows through the wire.If the wire were cut in half,making two wires of length L/2,and both wires were attached to the battery (the end of both wires attached to one terminal,and the other ends attached to the other terminal),what would be the total current flowing through the two wires?

Accepted Answer

A)  4I 
B)  2I 
C)  I 
D)  I/2 
E)  I/4 
A)  4I 
B)  2I 
C)  I 
D)  I/2 
E)  I/4

Question 9

In the figure a current of 6.0 A is drawn from the battery.What is the terminal voltage Vab of the battery?

Accepted Answer

A)  0.00 V 
B)  +12 V 
C)  +24 V 
D)  -12 V 
E)  -24 V 
A)  0.00 V 
B)  +12 V 
C)  +24 V 
D)  -12 V 
E)  -24 V

Question 10

A multiloop circuit is shown in the figure.Some circuit quantities are not labeled.It is not necessary to solve the entire circuit.The current I1 is closest to

Accepted Answer

A)  zero. 
B)  +0.2 A. 
C)  +0.4 A. 
D)  -0.2 A. 
E)  -0.4 A. 
A)  zero. 
B)  +0.2 A. 
C)  +0.4 A. 
D)  -0.2 A. 
E)  -0.4 A.

Question 11

An electric device delivers a current of 5.0 A to a device.How many electrons flow through this device in 10 s? (e = 1.60 × 10-19C)

Accepted Answer

A)  0.20 
B)  20 
C)  2.0 
D)  3.1 × 1020 
A)  0.20 
B)  20 
C)  2.0 
D)  3.1 × 1020

Question 12

As current flows through a uniform wire,the wire gets hotter because the electrons stop moving and therefore transform their lost kinetic energy into thermal energy in the wire.

Accepted Answer

A) True 
 B)False

Question 13

When a potential difference of 10 V is placed across a certain solid cylindrical resistor,the current through it is 2 A.If the diameter of this resistor is now tripled,the current will be

Accepted Answer

A)  2/9 A. 
B)  2/3 A. 
C)  2 A. 
D)  3 A. 
E)  18 A. 
A)  2/9 A. 
B)  2/3 A. 
C)  2 A. 
D)  3 A. 
E)  18 A.

Question 14

If the current density in a wire or radius R is given by J = kr,0 < r < R,what is the current in the wire?

Accepted Answer

A)  2πkR3/3 
B)  3πkR3/2 
C)  kR3/3 
D)  kR2 
E)  kR2/2 
A)  2πkR3/3 
B)  3πkR3/2 
C)  kR3/3 
D)  kR2 
E)  kR2/2

Question 15

The diameter of a 12-gauge copper wire is 0.081 in. The maximum safe current it can carry (in order to prevent fire danger in building construction)is 20 A. At this current,what is the drift velocity of the electrons? The number of electron carriers in 1.0 cm3 of copper is 8.5 × 1022 and e = 1.60 × 10-19 C.

Accepted Answer

A)  0.044 mm/s 
B)  0.44 mm/s 
C)  0.44 cm/s 
D)  0.44 m/s 
E)  4.4 cm/s 
A)  0.044 mm/s 
B)  0.44 mm/s 
C)  0.44 cm/s 
D)  0.44 m/s 
E)  4.4 cm/s

Question 16

Thirteen resistors are connected across points A and B as shown in the figure.If all the resistors are accurate to 2 significant figures,what is the equivalent resistance between points A and B?

Accepted Answer

A)  4.0 Ω 
B)  6.0 Ω 
C)  8.0 Ω 
D)  10 Ω 
E)  12 Ω 
A)  4.0 Ω 
B)  6.0 Ω 
C)  8.0 Ω 
D)  10 Ω 
E)  12 Ω

Question 17

The figure shows three identical lightbulbs connected to a battery having a constant voltage across its terminals.What happens to the brightness of lightbulb 1 when the switch S is closed?

Accepted Answer

A)  The brightness will increase momentarily then return to its previous level. 
B)  The brightness increases permanently. 
C)  The brightness will decrease momentarily then return to its previous level. 
D)  The brightness remains the same as before the switch is closed. 
E)  The brightness decreases permanently. 
A)  The brightness will increase momentarily then return to its previous level. 
B)  The brightness increases permanently. 
C)  The brightness will decrease momentarily then return to its previous level. 
D)  The brightness remains the same as before the switch is closed. 
E)  The brightness decreases permanently.

Question 18

A multiloop circuit is shown in the figure.Some circuit quantities are not labeled.It is not necessary to solve the entire circuit.The emf ε is closest to

Accepted Answer

A)  +3 V. 
B)  +19 V. 
C)  -3 V. 
D)  -10 V. 
E)  -1 V. 
A)  +3 V. 
B)  +19 V. 
C)  -3 V. 
D)  -10 V. 
E)  -1 V.

Question 19

A wire has a cross-sectional area of 0.10 mm2.If there are 4.0 × 1028 atoms per cubic meter in this wire,and if each atom contributes 2 free electrons,what is the drift velocity of the electrons when the current in the wire is 6.0 A? (e = 1.60 × 10-19C)

Accepted Answer

A)  0.0047 m/s 
B)  0.0092 m/s 
C)  0.94 m/s 
D)  0.019 m/s 
A)  0.0047 m/s 
B)  0.0092 m/s 
C)  0.94 m/s 
D)  0.019 m/s

Question 20

You are given a copper bar of dimensions 3 cm × 5 cm × 8 cm and asked to attach leads to it in order to make a resistor.
(a)If you want to achieve the SMALLEST possible resistance,you should attach the leads to the opposite faces that measure
 A)3 cm × 5 cm.
 B)3 cm × 8 cm.
 C)5 cm × 8 cm.
 D)Any pair of faces produces the same resistance.
(b) If you want to achieve the LARGEST possible resistance,you should attach the leads to the opposite faces that measure
 A)3 cm × 5 cm.
 B)3 cm × 8 cm.
 C)5 cm × 8 cm.
 D)Any pair of faces produces the same resistance

Accepted Answer

The answer of You are given a copper bar of...

Exam 31: Electric Circuits

For the circuit shown in the figure,what is the current through resistor R1?

Consider the circuit shown in the figure.Note that two currents are shown.Calculate the emfs ε1 and ε3.

Two identical resistors of resistance R = 24 Ω and a variable resistor Rx are connected to an ideal battery of voltage V as shown in the figure. What should be the value of the variable resistance Rx to make the voltage across the two parallel resistors equal to .

In the circuit shown in the figure,four identical resistors labeled A to D are connected to a battery as shown.S1 and S2 are switches.Which of the following actions would result in the GREATEST amount of current through resistor A?

A multiloop circuit is shown in the figure.Some circuit quantities are not labeled.It is not necessary to solve the entire circuit.The current I2 is closest to

When four identical resistors are connected to an ideal battery of voltage V = 10 V as shown in the figure,the current I is equal to 0.20 A.What is the value of the resistance R of the resistors?

In the figure a current of 6.0 A is drawn from the battery.What is the terminal voltage Vab of the battery?

A multiloop circuit is shown in the figure.Some circuit quantities are not labeled.It is not necessary to solve the entire circuit.The current I1 is closest to

An electric device delivers a current of 5.0 A to a device.How many electrons flow through this device in 10 s? (e = 1.60 × 10-19C)

As current flows through a uniform wire,the wire gets hotter because the electrons stop moving and therefore transform their lost kinetic energy into thermal energy in the wire.

When a potential difference of 10 V is placed across a certain solid cylindrical resistor,the current through it is 2 A.If the diameter of this resistor is now tripled,the current will be

If the current density in a wire or radius R is given by J = kr,0 < r < R,what is the current in the wire?

Thirteen resistors are connected across points A and B as shown in the figure.If all the resistors are accurate to 2 significant figures,what is the equivalent resistance between points A and B?

The figure shows three identical lightbulbs connected to a battery having a constant voltage across its terminals.What happens to the brightness of lightbulb 1 when the switch S is closed?

A multiloop circuit is shown in the figure.Some circuit quantities are not labeled.It is not necessary to solve the entire circuit.The emf ε is closest to

A wire has a cross-sectional area of 0.10 mm2.If there are 4.0 × 1028 atoms per cubic meter in this wire,and if each atom contributes 2 free electrons,what is the drift velocity of the electrons when the current in the wire is 6.0 A? (e = 1.60 × 10-19C)

Foundations

A: Foundations

Motion in One Dimension

Acceleration

Momentum

Energy

Principle of Relativity

Interactions

Force

Work

Motion in a Plane

Motion in a Circle

Torque

Gravity

Special Relativity

Periodic Motion

Waves in One Dimension

Waves in Two and Three Dimensions

Fluids

Entropy

Energy Transferred Thermally

Degradation of Energy

Electric Interactions

The Electric Field

Gausss Law

Work and Energy in Electrostatics

Charge Separation and Storage

Magnetic Interactions

Magnetic Fields of Charged Particles in Motion

Changing Magnetic Fields

Changing Electric Fields

Electronics

Ray Optics

Wave and Particle Optics

Filters

For the circuit shown in the figure,what is the current through resistor R₁?

Consider the circuit shown in the figure.Note that two currents are shown.Calculate the emfs ε₁ and ε₃.

Two identical resistors of resistance R = 24 Ω and a variable resistor R_x are connected to an ideal battery of voltage V as shown in the figure. What should be the value of the variable resistance R_x to make the voltage across the two parallel resistors equal to .

In the circuit shown in the figure,four identical resistors labeled A to D are connected to a battery as shown.S₁ and S₂ are switches.Which of the following actions would result in the GREATEST amount of current through resistor A?

A multiloop circuit is shown in the figure.Some circuit quantities are not labeled.It is not necessary to solve the entire circuit.The current I₂ is closest to

In the figure a current of 6.0 A is drawn from the battery.What is the terminal voltage V_ab of the battery?

A multiloop circuit is shown in the figure.Some circuit quantities are not labeled.It is not necessary to solve the entire circuit.The current I₁ is closest to

An electric device delivers a current of 5.0 A to a device.How many electrons flow through this device in 10 s? (e = 1.60 × 10^-19C)

A wire has a cross-sectional area of 0.10 mm².If there are 4.0 × 10²⁸ atoms per cubic meter in this wire,and if each atom contributes 2 free electrons,what is the drift velocity of the electrons when the current in the wire is 6.0 A? (e = 1.60 × 10^-19C)