Q: Which equation correctly defines the electric potential $$V at a $$point in space?

$$V = \frac{\text{EPE}}{q_0$}$$

Q: A $$2.0 \times 10$$^{-6}$$\ \text{C}$$ charge moves through a potential difference of $$120\ \text{V}. $$What is the change in electric potential energy?

$$2.4 \times 10$$^{-3}$$\ \text{J}$$

Q: A Van de Graaff generator accelerates an electron across a $$+100,000\ \text{V}$$ potential difference. What is the change in electric potential energy of the electron? ($$q = -1.6 \times 10$$^{-19}$$\ \text{C})$$

$$-1.6 \times 10$$^{-14}$$\ \text{J}$$

Q: What is the value of $$1\ \text{eV} ($$electron volt) in joules?

$$1.60 \times 10$$^{-19}$$\ \text{J}$$

Question 1

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

Accepted Answer

The number of electric field lines per cross-sectional area is proportional to the strength of the electric field in that region.

Question 2

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

Accepted Answer

Away from the positive charge

Question 3

At electrostatic equilibrium, what is the electric field inside a conductor?

Accepted Answer

It is zero.

Question 4

Which of the following best describes the electric field just outside the surface of a conductor at equilibrium?

Accepted Answer

It is perpendicular to the surface.

Question 5

A charge $$+q is $$suspended at the center of a hollow, electrically neutral, spherical conductor. What is the induced charge on the interior and exterior surfaces?

Accepted Answer

(a) $$-q on $$the interior, $$+q on $$the exterior

Question 6

Which equation correctly defines the electric potential $$V at a $$point in space?

Accepted Answer

$$V = \frac{	ext{EPE}}{q_0$}$$

Question 7

A $$2.0 	imes 10$$^{-6}$$\ 	ext{C}$$ charge moves through a potential difference of $$120\ 	ext{V}. $$What is the change in electric potential energy?

Accepted Answer

$$2.4 	imes 10$$^{-3}$$\ 	ext{J}$$

Question 8

Which of the following is a correct analogy between gravitational and electric potential energy?

Accepted Answer

Gravitational potential energy depends on mass, while electric potential energy depends on charge.

Question 9

A parallel-plate capacitor has a charge of $$4.0\ 	ext{nC} on $$each plate, an area of $$0.01\ 	ext{m}^2$$, and a plate separation of $$1.0\ 	ext{mm}. $$What is the potential difference between the plates? (Use $$\$$varepsilon_0$$ = 8.85 	imes 10$$^{-12}$$\ 	ext{C}^2/	ext{N} \cdot 	ext{m}^2)$$

Accepted Answer

$$-4.5\ 	ext{V}$$

Question 10

What is the electric potential at a distance $$r$$ from a point charge $$q$$?

Accepted Answer

$$V = \frac{kq}{r}$$

Question 11

Two point charges, $$+8.0 	imes 10$$^{-9}$$\ 	ext{C}$$ and $$-8.0 	imes 10$$^{-9}$$\ 	ext{C}$$, are separated by $$0.40\ 	ext{m}. $$What is the electric potential at the midpoint between them?

Accepted Answer

$$0\ 	ext{V}$$

Question 12

A Van de Graaff generator accelerates an electron across a $$+100,000\ 	ext{V}$$ potential difference. What is the change in electric potential energy of the electron? ($$q = -1.6 	imes 10$$^{-19}$$\ 	ext{C})$$

Accepted Answer

$$-1.6 	imes 10$$^{-14}$$\ 	ext{J}$$

Question 13

Which of the following is true about the motion of a positive test charge in an electric field?

Accepted Answer

It accelerates from a region of higher electric potential to a region of lower electric potential.

Question 14

What is the value of $$1\ 	ext{eV} ($$electron volt) in joules?

Accepted Answer

$$1.60 	imes 10$$^{-19}$$\ 	ext{J}$$

Question 15

If two point charges $$+2q$$ and $$-q$$ are fixed in place, how many points along the line passing through both charges have zero electric potential?

Accepted Answer

Two

Question 16

Which of the following is NOT a correct property of electric field lines?

Accepted Answer

They can form closed loops in free space.

Question 17

A negative charge is released from rest at a point of low electric potential. What will it do?

Accepted Answer

It will accelerate toward a region of higher potential.

Question 18

Which of the following best explains why a conductor shields its interior from external electric fields?

Accepted Answer

The charges inside the conductor move to cancel the external field, resulting in zero net field inside.

Electric Fields and Electric Potential: Study Notes

Study Guide - Practice Questions

Study Guide - Flashcards