Q: Which of the following is a correct statement about the work-energy theorem?

$$W_{a \to b} = \Delta K = \frac{1}{2}mv_f^2$ - \frac{1}{2}mv_o^2$

Question 1

Which of the following best describes the direction of electric field lines around a single positive point charge, as shown in the first image?

Accepted Answer

They radiate outward from the charge in all directions.

Question 2

According to Coulomb's Law, what happens to the electric force between two point charges if the distance between them is doubled?

Accepted Answer

The force decreases by a factor of 4.

Question 3

Which equation correctly expresses the electric field $$\vec{E}$$ due to a point charge $$Q at a $$distance $$r$$?

Accepted Answer

$$\vec{E} = \frac{kQ}{r^2$} \hat{r}$$

Question 4

In the second image, what is the direction of the electric field at the midpoint between a positive and a negative charge?

Accepted Answer

From the positive charge toward the negative charge.

Question 5

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

Accepted Answer

Electric field lines can cross each other.

Question 6

A positive test charge is moved in the direction of the electric field. What happens to its electric potential energy?

Accepted Answer

It decreases.

Question 7

What is the SI unit of electric potential?

Accepted Answer

Volt ($$V)$$

Question 8

A charge $$q_0$$ moves from point $$a to $$point $$b in a $$uniform electric field $$\vec{E}$$, as shown in the seventh image. If $$y_b \u003e y_a$$, what is the work done by the electric field?

Accepted Answer

$$W = -q_0$ E (y_b - y_a)$$

Question 9

Which of the following is a property of a conservative force?

Accepted Answer

The work done is path-independent.

Question 10

A negative charge is released from rest in a uniform electric field, as shown in the ninth image. What happens to its electric potential energy as it moves?

Accepted Answer

It increases.

Question 11

Which equation gives the electric potential $$V at a $$distance $$r$$ from a point charge $$Q$$?

Accepted Answer

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

Question 12

A point charge $$q_2 = -e$ is brought from infinity to a distance r$ from another point charge q_1$ = -e. $$What is the change in electric potential energy?

Accepted Answer

$$\Delta U = \frac{k e^2$}{r}$$

Question 13

If the electric field between two parallel plates is $$E = \frac{\sigma}{\$$epsilon_0$$}$$, what does $$\sigma$$ represent?

Accepted Answer

Surface charge density

Question 14

Which of the following best describes the relationship between electric potential energy $$U$$ and electric potential $$V$$ for a charge $$q_0$$?

Accepted Answer

$$U = q_0$ V$$

Question 15

A positive charge is moved from a lower potential to a higher potential. What can be said about the work done by the electric field?

Accepted Answer

The electric field does negative work.

Question 16

Which of the following is true about the electric field inside a conductor in electrostatic equilibrium?

Accepted Answer

The electric field is zero.

Question 17

A charge $$q is $$placed in a uniform electric field $$E$$ and moves a distance $$d$$ parallel to the field. What is the change in electric potential energy?

Accepted Answer

$$\Delta U = -qEd$$

Question 18

Which of the following is a correct statement about the work-energy theorem?

Accepted Answer

$$W_{a 	o b} = \Delta K = \frac{1}{2}mv_f^2$ - \frac{1}{2}mv_o^2$

Question 19

If the net electric field at a point is zero, what can be said about the electric field lines at that point?

Accepted Answer

No field lines pass through that point.

Question 20

Which of the following best describes the energy transformation when a charged particle accelerates in an electric field?

Accepted Answer

Electric potential energy is converted to kinetic energy.

Electric Potential and Electric Potential Energy

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