Question 1

Which equation correctly represents the total electric potential energy $$U of $$three point charges $$q_1$$, $$q_2$$, and $$q_3$$ separated by distances $$r_{12}$$, $$r_{23}$$, and $$r_{13}$$?

Accepted Answer

$$U = \frac{1}{4\pi\$$varepsilon_0$$} \left( \frac{q_1q_2}{r_{12}} + \frac{q_2q_3}{r_{23}} + \frac{q_1q_3}{r_{13}} \right)$$

Question 2

A field is a physical quantity that has a value at every location in space. Which of the following is a vector field?

Accepted Answer

Electric field

Question 3

What is the direction of the electric field produced by a positive point charge?

Accepted Answer

Away from the charge

Question 4

Which principle allows us to calculate the net electric field at a location in space by summing the individual fields from all charges?

Accepted Answer

Superposition principle

Question 5

Given three charges at the corners of a triangle, which pairwise interaction does NOT depend on the presence of the third charge?

Accepted Answer

The interaction between $$q_1$$ and $$q_2$$

Question 6

If an electron is released from rest in a uniform electric field, what is the nature of its motion?

Accepted Answer

It moves in a straight line along the field lines

Question 7

Which equation gives the electric field $$E at a $$distance $$r$$ from a point charge $$Q$$?

Accepted Answer

$$E = \frac{1}{4\pi\$$varepsilon_0$$} \frac{Q}{r^2$}$$

Question 8

In an electric field diagram, what does the density of field lines represent?

Accepted Answer

The strength of the field

Question 9

A negative test charge is placed in an electric field created by a positive source charge. What is the direction of the force on the test charge?

Accepted Answer

Toward the positive source charge

Question 10

Which of the following statements about electric field lines is TRUE?

Accepted Answer

Field lines begin on positive charges and end on negative charges

Question 11

A proton is placed in a uniform electric field pointing to the right. What is the direction of the force on the proton?

Accepted Answer

To the right

Question 12

Which equation describes the force $$F on a $$charge $$q in an $$electric field $$E$$?

Accepted Answer

$$F = qE$$

Question 13

If the initial velocity of a charge is perpendicular to a uniform electric field, what is the resulting trajectory?

Accepted Answer

Parabolic

Question 14

Which equation gives the acceleration $$a of a $$particle with mass $$m$$ and charge $$q in an $$electric field $$E$$?

Accepted Answer

$$a = \frac{qE}{m}$$

Question 15

In a parallel plate capacitor, what is the direction of the electric field between the plates?

Accepted Answer

From the positive plate to the negative plate

Question 16

Which equation gives the electric field $$E$$ between two parallel plates with charge $$Q$$ and area $$A$$?

Accepted Answer

$$E = \frac{Q}{\$$varepsilon_0$$ A}$$

Question 17

A system of two positive point charges is shown. Where is the electric field strongest?

Accepted Answer

Near the charges

Question 18

If the number of electric field lines leaving a charge is doubled, what happens to the magnitude of the charge?

Accepted Answer

It is doubled

Question 19

Which of the following best describes the relationship between electric field lines and electric field vectors?

Accepted Answer

Field vectors are tangent to field lines at each point

Question 20

A charged particle moves in a region where the electric field is zero. What happens to the particle?

Accepted Answer

It moves at constant velocity

Electric Fields and Potential Energy: Study Notes for College Physics

Study Guide - Practice Questions

Study Guide - Flashcards