Question 1

Which of the following best describes the analogy between energy and money, as presented in Table 7.1?

Accepted Answer

Energy, like money, can take multiple forms and be transformed between them without changing the total amount.

Question 2

A slingshot is pulled back and held in place, as shown in the image. What type of energy is primarily stored in the stretched slingshot before release?

Accepted Answer

Elastic potential energy

Question 3

A skateboarder starts at rest at the top of a half-pipe, as shown. As the skateboarder descends, which energy transformation primarily occurs?

Accepted Answer

Gravitational potential energy is converted to kinetic energy.

Question 4

When a block slides across a surface and comes to rest due to friction, as shown in the image, what happens to the block's kinetic energy?

Accepted Answer

It is converted into internal energy (thermal energy) due to friction.

Question 5

A slingshot is stretched and then released, launching a rock upward. At the highest point of the rock's trajectory, which statement is true?

Accepted Answer

The rock has zero kinetic energy and maximum gravitational potential energy.

Question 6

A tractor pulls a sled with a force $$\vec{F} at an $$angle $$\phi$$ above the horizontal for a distance $$s. $$What is the correct expression for the work done by the tractor on the sled?

Accepted Answer

$$W = F s \cos \phi$$

Question 7

If a force $$\vec{F}$$ acts perpendicular to the displacement $$\vec{s} of an $$object, what is the work done by the force?

Accepted Answer

The work is zero.

Question 8

A spring is stretched from $$x = 0 to$$ $$x = X. $$What is the work done by the external force in stretching the spring?

Accepted Answer

$$W = \frac{1}{2} k X^2$

Question 9

A woman weighing 600 N steps onto a bathroom scale, compressing the spring by 1.0 cm. What is the force constant $$k of $$the spring?

Accepted Answer

$$k = 6000 \ \mathrm{N/m}$$

Question 10

A block of mass $$m is $$released from rest at height $$h on a $$frictionless ramp. What is its speed at the bottom of the ramp?

Accepted Answer

$$v = \sqrt{2gh}$$

Question 11

A glider of mass $$m = 0.200 \ \mathrm{kg} is $$attached to a spring with $$k = 5.00 \ \mathrm{N/m}$$ and is pulled to $$x_i = 0.100 \ \mathrm{m}$$, then released from rest. What is its speed when it passes $$x_f = 0.0800 \ \mathrm{m}$$?

Accepted Answer

$$v = \sqrt{\frac{k}{m} (x_i^2$ - x_f^2$)}$$

Question 12

A 2000 kg elevator falls at 8.00 m/s and is stopped by a spring that compresses 3.00 m. What is the required force constant $$k of $$the spring?

Accepted Answer

$$k = \frac{m v^2$ + 2 m g x}{2 x^2$}$$

Question 13

Which of the following statements about conservative forces is correct?

Accepted Answer

The work done by a conservative force can be expressed as the difference in potential energy between two points.

Question 14

A crate is pushed up a ramp and comes to rest after sliding a certain distance due to friction. Which of the following best describes the energy transformation?

Accepted Answer

Kinetic energy is converted to thermal energy due to friction.

Work, Energy, and Momentum: Structured Study Notes for Physics with Calculus

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