Question 1

A 1500-W heater is connected to a 120-V line. How much heat energy does it produce in 2.0 hours?

Accepted Answer

A)  1.5 kJ 
B)  3.0 kJ 
C)  0.18 MJ 
D)  11 MJ 
E)  18 MJ 
A)  1.5 kJ 
B)  3.0 kJ 
C)  0.18 MJ 
D)  11 MJ 
E)  18 MJ

Question 2

For the circuit shown in the figure,determine the current in
(a)the 7.0-Ω resistor.
(b)the 8.0-Ω resistor.
(c)the 4.0-Ω resistor.

Accepted Answer

(a)1.6 A

Question 3

Three resistors are connected across an ideal 2.0-V DC battery as shown in the figure.
(a)At what rate does the battery supply energy to the resistors?
(b)At what rate is heat produced in the 6.0-Ω resistor?

Accepted Answer

The answer of Three resistors are connected across an ideal...

Question 4

In the circuit shown in the figure,an ideal ohmmeter is connected across ab with the switch S open.All the connecting leads have negligible resistance.The reading of the ohmmeter will be closest to

Accepted Answer

A)  7.5 Ω. 
B)  10 Ω. 
C)  30 Ω. 
D)  40 Ω. 
E)  60 Ω. 
A)  7.5 Ω. 
B)  10 Ω. 
C)  30 Ω. 
D)  40 Ω. 
E)  60 Ω.

Question 5

For the circuit shown in the figure,the current in the 8-Ω resistor is 0.50 A,and all quantities are accurate to 2 significant figures.What is the current in the 2-Ω resistor?

Accepted Answer

A)  2.25 A 
B)  0.75 A 
C)  4.5 A 
D)  9.5 A 
E)  6.4 A 
A)  2.25 A 
B)  0.75 A 
C)  4.5 A 
D)  9.5 A 
E)  6.4 A

Question 6

Two cables of the same length are made of the same material,except that one cable has twice the diameter of the other cable.When the same potential difference is maintained across both cables,which of the following statements are true? (There may be more than one correct choice.)

Accepted Answer

A)  The same current flows through both cables. 
B)  Both cables carry the same current density. 
C)  The electrons have the same drift velocity in both cables. 
D)  The current in the thin cable is twice as great as the current in the thick cable. 
E)  The current in the thin cable is four times as great as the current in the thick cable. 
A)  The same current flows through both cables. 
B)  Both cables carry the same current density. 
C)  The electrons have the same drift velocity in both cables. 
D)  The current in the thin cable is twice as great as the current in the thick cable. 
E)  The current in the thin cable is four times as great as the current in the thick cable.

Question 7

When a 100-Ω resistor is connected across the terminals of a battery of emf ε and internal resistance r,the battery delivers 0.794 W of power to the 100-Ω resistor. When the 100-Ω resistor is replaced by a 200-Ω resistor,the battery delivers 0.401 W of power to the 200-Ω resistor.What are the emf and internal resistance of the battery?

Accepted Answer

A)  ε = 10.0 V, r = 5.02 Ω 
B)  ε = 4.50 V, r = 4.00 Ω 
C)  ε = 9.00 V, r = 2.04 Ω 
D)  ε = 9.00 V, r = 1.01 Ω 
E)  ε = 12.0 V, r = 6.00 Ω 
A)  ε = 10.0 V, r = 5.02 Ω 
B)  ε = 4.50 V, r = 4.00 Ω 
C)  ε = 9.00 V, r = 2.04 Ω 
D)  ε = 9.00 V, r = 1.01 Ω 
E)  ε = 12.0 V, r = 6.00 Ω

Question 8

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 with a current that is 50% of the current rating of the bulb,what is the actual power drawn by the bulb?

Accepted Answer

A)  10 W 
B)  15 W 
C)  20 W 
D)  25 W 
E)  30 W 
A)  10 W 
B)  15 W 
C)  20 W 
D)  25 W 
E)  30 W

Exam 31: Electric Circuits

A 1500-W heater is connected to a 120-V line. How much heat energy does it produce in 2.0 hours?

For the circuit shown in the figure,determine the current in (a)the 7.0-Ω resistor. (b)the 8.0-Ω resistor. (c)the 4.0-Ω resistor.

Three resistors are connected across an ideal 2.0-V DC battery as shown in the figure. (a)At what rate does the battery supply energy to the resistors? (b)At what rate is heat produced in the 6.0-Ω resistor?

In the circuit shown in the figure,an ideal ohmmeter is connected across ab with the switch S open.All the connecting leads have negligible resistance.The reading of the ohmmeter will be closest to

For the circuit shown in the figure,the current in the 8-Ω resistor is 0.50 A,and all quantities are accurate to 2 significant figures.What is the current in the 2-Ω resistor?

Two cables of the same length are made of the same material,except that one cable has twice the diameter of the other cable.When the same potential difference is maintained across both cables,which of the following statements are true? (There may be more than one correct choice.)

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