Q: A block is lifted vertically from $$y_1 to$$ $$y_2$$ ($$y_2$$ \u003e $$y_1). $$What is the change in gravitational potential energy?

$$\Delta U_{\text{grav}} = mg(y_2$ - y_1$)$$

Q: A spring with spring constant $$k is $$compressed by a distance $$x. $$What is the elastic potential energy stored in the spring?

$$U_{\text{el}} = \frac{1}{2}kx^2$

Q: Which equation represents the law of conservation of energy for a system with nonconservative forces?

$$\Delta K + \Delta U + \Delta U_{\text{int}} = 0$$

Q: A block slides down a curved path from height $$y_1 to$$ $$y_2. $$What is the work done by gravity?

$$W_{\text{grav}} = mg(y_1$ - y_2$)$$

Question 1

A basketball is dropped from a height of 2 m. Ignoring air resistance, what happens to its gravitational potential energy and kinetic energy as it falls?

Accepted Answer

Gravitational potential energy decreases, kinetic energy increases.

Question 2

Which equation correctly expresses the gravitational potential energy of a particle near Earth's surface?

Accepted Answer

$$U_{	ext{grav}} = mgy$$

Question 3

A block is lifted vertically from $$y_1 to$$ $$y_2$$ ($$y_2$$ \u003e $$y_1). $$What is the change in gravitational potential energy?

Accepted Answer

$$\Delta U_{	ext{grav}} = mg(y_2$ - y_1$)$$

Question 4

A spring with spring constant $$k is $$compressed by a distance $$x. $$What is the elastic potential energy stored in the spring?

Accepted Answer

$$U_{	ext{el}} = \frac{1}{2}kx^2$

Question 5

A glider attached to a spring oscillates on an air track. At the maximum displacement $$x = A$$, what is true about its kinetic and potential energies?

Accepted Answer

Kinetic energy is zero, potential energy is maximum.

Question 6

Which of the following statements about conservative forces is correct?

Accepted Answer

The work done by a conservative force is zero if the starting and ending points are the same.

Question 7

A runner moves from the base to the top of a hill by three different paths. Which statement is true about the work done by gravity?

Accepted Answer

The work done by gravity is the same for all three paths.

Question 8

A car tire heats up as it rolls due to internal friction. What type of force is responsible for this energy transformation?

Accepted Answer

Nonconservative force

Question 9

Which equation represents the law of conservation of energy for a system with nonconservative forces?

Accepted Answer

$$\Delta K + \Delta U + \Delta U_{	ext{int}} = 0$$

Question 10

For a spring, the force as a function of displacement $$x is $$given by:

Accepted Answer

$$F_x = -kx$$

Question 11

A hiker climbs to a higher elevation in Banff National Park. What happens to their gravitational potential energy?

Accepted Answer

It increases.

Question 12

Which equation gives the force from a potential energy function $$U(x) in $$one dimension?

Accepted Answer

$$F_x = -\frac{dU}{dx}$$

Question 13

A block slides down a curved path from height $$y_1 to$$ $$y_2. $$What is the work done by gravity?

Accepted Answer

$$W_{	ext{grav}} = mg(y_1$ - y_2$)$$

Question 14

Which of the following is true about elastic potential energy for an ideal spring?

Accepted Answer

It is never negative.

Question 15

A trampoline jumper ascends. What happens to their kinetic and elastic potential energies?

Accepted Answer

Kinetic energy decreases, elastic potential energy decreases.

Question 16

For a potential energy function $$U(x)$$, at which point is the equilibrium stable?

Accepted Answer

Where $$U(x) is at a $$minimum.

Question 17

In three dimensions, the force from a potential energy function $$U(x, y, z) is $$given by:

Accepted Answer

$$\vec{F} = -
abla U$$

Question 18

A parachutist descends at constant speed. What happens to their mechanical energy?

Accepted Answer

It decreases.

Question 19

Which of the following is NOT a property of a conservative force?

Accepted Answer

It dissipates energy as heat.

Question 20

A block attached to a spring is released from $$x = A. At$$ $$x = 0$$, what is true about its energy?

Accepted Answer

All energy is kinetic.

Potential Energy and Energy Conservation: Structured Study Notes

스터디 가이드 - 연습 문제

학습 가이드 - 플래시카드