Q: A hockey puck slides across frictionless ice at a constant velocity. What is the net force acting on the puck?

$$F_{\text{net}} = 0\ \text{N}$$

Question 1

Which of the following best describes the condition for an object to be in mechanical equilibrium?

Accepted Answer

The net force acting on the object must be zero.

Question 2

A hockey puck slides across frictionless ice at a constant velocity. What is the net force acting on the puck?

Accepted Answer

$$F_{	ext{net}} = 0\ 	ext{N}$$

Question 3

Jerry pulls a crate with a force of 200 N to the right across a rough floor at constant speed. What is the magnitude and direction of the friction force?

Accepted Answer

200 N to the left

Question 4

Which of the following statements about friction is correct?

Accepted Answer

Friction always acts opposite to the direction of motion.

Question 5

A 1-kg brick weighs approximately how much on Earth?

Accepted Answer

9.8 N

Question 6

If the net force acting on an object doubles, what happens to its acceleration?

Accepted Answer

It doubles.

Question 7

Which equation correctly relates force, mass, and acceleration according to Newton’s Second Law?

Accepted Answer

$$F = m a$$

Question 8

A 50 kg student stands on the surface of the Earth. What is the gravitational force between the student and the Earth? (Use $$g = 9.8\ 	ext{m/s}^2)$$

Accepted Answer

$$F = 490\ 	ext{N}$$

Question 9

Which of the following is true about mass and inertia?

Accepted Answer

Mass and inertia are directly proportional.

Question 10

A car and a bicycle are both at rest. Which has more inertia and why?

Accepted Answer

The car, because it has more mass.

Question 11

A box is pushed across a floor and moves at constant velocity. Which statement is true?

Accepted Answer

The applied force equals the friction force.

Question 12

If the mass of an object is tripled while the net force remains the same, what happens to the acceleration?

Accepted Answer

It becomes one-third as large.

Question 13

Which of the following best describes terminal velocity?

Accepted Answer

The speed at which the net force on a falling object is zero.

Question 14

A 7 kg rock weighs 11.4 N on the Moon. What is the acceleration due to gravity on the Moon?

Accepted Answer

$$g = 1.63\ 	ext{m/s}^2$$

Question 15

Which of the following is NOT a property of friction between solid surfaces?

Accepted Answer

Friction depends on the area of contact.

Question 16

A satellite orbits Earth in a nearly circular path. What force provides the centripetal acceleration?

Accepted Answer

The gravitational force between the satellite and Earth.

Question 17

If the distance between two masses is tripled, what happens to the gravitational force between them?

Accepted Answer

It becomes one-ninth as large.

Question 18

Which of the following best explains why a truck is harder to start moving than a bicycle?

Accepted Answer

The truck has more inertia due to its greater mass.

Question 19

Which equation is used to calculate the weight of an object?

Accepted Answer

$$W = mg$$

Question 20

A box is at rest on a table. Which of the following statements is true?

Accepted Answer

The normal force equals the weight of the box.

Forces, Equilibrium, and Free-Body Diagrams – Step-by-Step Physics Guidance

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