Chapter 24

Question 1

In the figure, two points A and B are located within a region in which there is an electric field. How would you describe the potential difference V = VB - VA? (a is closer to the source of electric field)

Answer 1

b

Question 2

n the figure, two points A and B are located within a region in which there is an electric field. How would you describe the change in potential energy of the charge–field system for this process if you have a negative test charge?
(a) It is positive.
(b) It is negative.
(c) It is zero.

Answer 2

a

Question 3

The labeled points in the figure are on a series of equipotential surfaces associated with an electric field. Rank (from greatest to least) the work done by the electric field on a positively charged particle that moves from A to B, from B to C, from C to D, and from D to E.

Answer 3

B to C, C to D, A to B, D to E

Question 4

In the figure, take q2 to be a negative source charge andq1 to be a second charge whose sign can be changed. Ifq1 is initially positive and is changed to a charge of thesame magnitude but negative, what happens to the potential at the position of q1 due to q2?
(a) It increases.
(b) It decreases.
(c) It remains the same.

Answer 4

c (q refers to the reference charge)

Question 5

In the figure, take q2 to be a negative source charge and q1 to be a second charge whose sign can be changed. When q1 is changed from positive to negative, what happens to the potential energy of the two-charge system?
(a) It increases.
(b) It decreases.
(c) It remains the same

Answer 5

a

Question 6

In a certain region of space, the electric potential is zero everywhere along the x-axis. From this information, you can conclude that the x component of the electric field in this region is
(a) zero,
(b) in the positive x direction, or
(c) in the negative x direction.

Answer 6

a

Question 7

Suppose the electric potential is +2 V everywhere alongthe x axis. From this information, you can conclude thatthe x component of the electric field in this region is
(a) zero,
(b) in the positive x direction, or
(c) in the negative x direction.

Answer 7

a

Question 8

Consider the equipotential surfaces shown in thefigure. In this region of space, what is the approximatedirection of the electric field?
1. It is out of the page.
2. It is into the page.
3. It is toward the top of the page.
4. It is toward the bottom of the page.
5. The field is zero.

Answer 8

4

Question 9

The electric potential at x = 3.00 m is 120 V, and theelectric potential at x = 5.00 m is 190 V. What is the xcomponent of the electric field in this region,assuming the field is uniform?1. 140 N/C
2. 140 N/C
3. 35.0 N/C
4. 35.0 N/C
5. 75.0 N/C

Answer 9

4. (M)

Question 10

Rank the potential energies of the four systems ofparticles shown in the figure from largest to smallest.Include equalities if appropriate.
1. c > a > b = d
2. b > c = d > a
3. d > a > c > b
4. a > b = d > c

Answer 10

4

Question 11

In a certain region of space, a uniform electric field isin the x direction. A particle with negative charge iscarried from x = 20.0 cm to x = 60.0 cm. The electricpotential energy of the charge-field system:
1. increases.
2. remains constant.
3. decreases.
4. changes unpredictably.

Answer 11

1 (formula)

Question 12

In a certain region of space, a uniform electric field isin the x direction. A particle with negative charge iscarried from x = 20.0 cm to x = 60.0 cm. The particlehas moved to a position where the electric potential is
1. higher than before.
2. unchanged.
3. lower than before.
4. unpredictable.

Answer 12

3

Question 13

Rank the electric potentials at the four points shown inthe figure from largest to smallest.
1. C > A > D > B
2. B > C > D > A
3. A > C > B > D
4. D > C > B > A

Answer 13

4