Question 1

A block of mass $$m$$ slides across a horizontal surface with an initial speed $$v_0. $$The coefficient of kinetic friction between the block and the surface is $$\mu_k. $$What is the distance $$d$$ the block travels before coming to rest?

Accepted Answer

$$d = \frac{v_0$^2}{2\mu_k g}$$

Question 2

Which of the following best describes the direction of the frictional force acting on an object sliding to the right on a rough surface?

Accepted Answer

It acts to the left, opposing the motion.

Question 3

A ball is dropped from rest and falls under gravity through air. At terminal speed, which statement is true?

Accepted Answer

The net force on the ball is zero.

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_{sp} = \frac{1}{2}kx^2$

Question 5

A 2 kg object is attached to a rope and hangs vertically. What is the tension in the rope if the object is at rest?

Accepted Answer

$$T = 2g$$

Question 6

Which of the following is a correct statement of Newton's Third Law?

Accepted Answer

For every action, there is an equal and opposite reaction.

Question 7

A car of mass $$m$$ moves in a circle of radius $$r at $$constant speed $$v. $$What is the magnitude of the centripetal force acting on the car?

Accepted Answer

$$F_c = \frac{mv^2$}{r}$$

Question 8

A block is pulled across a rough surface at constant velocity. Which statement is true about the forces acting on the block?

Accepted Answer

The applied force equals the frictional force.

Question 9

Which equation correctly relates work done by a constant force $$\vec{F}$$ over a displacement $$\vec{d}$$?

Accepted Answer

$$W = \vec{F} \cdot \vec{d}$$

Question 10

A ball of mass $$m is $$thrown vertically upward with initial speed $$v_0. $$Ignoring air resistance, what is the maximum height $$h$$ reached by the ball?

Accepted Answer

$$h = \frac{v_0$^2}{2g}$$

Question 11

Which of the following best describes the energy transformation when a car brakes to a stop?

Accepted Answer

Kinetic energy is transformed into thermal energy due to friction.

Question 12

A block of mass $$m is $$attached to a spring and oscillates horizontally with no friction. What is the total mechanical energy of the system?

Accepted Answer

$$E = \frac{1}{2}kA^2$

Question 13

Which of the following is true about the conservation of energy in an isolated system?

Accepted Answer

The total energy remains constant.

Question 14

A ball of mass $$m is $$dropped from height $$h$$ above the ground. What is its speed just before hitting the ground, neglecting air resistance?

Accepted Answer

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

Question 15

A block of mass $$m is $$pulled up a ramp at constant speed. The ramp makes an angle $$	heta$$ with the horizontal. What is the minimum force required to pull the block up the ramp, neglecting friction?

Accepted Answer

$$F = mg \sin 	heta$$

Question 16

Which of the following is a correct expression for gravitational potential energy near Earth's surface?

Accepted Answer

$$U_g = mgh$$

Question 17

A ball moves in a circle of radius $$r at $$constant speed $$v. $$What is the direction of its acceleration?

Accepted Answer

Toward the center of the circle.

Question 18

A block of mass $$m is $$connected to another block of mass $$M by a $$light string over a frictionless pulley. If $$M \u003e m$$, what is the acceleration of the system?

Accepted Answer

$$a = \frac{(M - m)g}{M + m}$$

Question 19

Which of the following is true about dissipative forces such as friction?

Accepted Answer

They transform mechanical energy into thermal energy.

Forces, Newton's Laws, Circular Motion, and Energy: Physics Study Notes

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