Question 1

A 40 N force pushes a 20 kg object to the left. What is the object's acceleration?

Accepted Answer

$$a = 2\ \mathrm{m/s^2$}$$

Question 2

Which of the following best describes the relationship between force, mass, and acceleration according to Newton's Second Law?

Accepted Answer

$$F = m \cdot a$$

Question 3

A 5 kg object is pushed right by a 20 N force while also being pulled right by a 10 N force. What is the object's acceleration?

Accepted Answer

$$a = 6\ \mathrm{m/s^2$}$$

Question 4

If the mass of an object is halved, the weight of the object is

Accepted Answer

halved.

Question 5

Which of the following is NOT a property of friction?

Accepted Answer

It acts in the same direction as motion.

Question 6

A 50 kg girl stands on a scale. What is the normal force exerted by the scale?

Accepted Answer

$$F_N = 490\ \mathrm{N}$$

Question 7

When Sanjay pushes a refrigerator across a kitchen floor at a constant speed, the force of friction between the refrigerator and the floor is

Accepted Answer

equal to Sanjay's push.

Question 8

A 600 kg car accelerates to the right at $$0.5\ \mathrm{m/s^2$}. If $$the force of friction is $$1000\ \mathrm{N}$$, what force is the engine providing?

Accepted Answer

$$F = 1300\ \mathrm{N}$$

Question 9

Which of the following statements about mass and weight is correct?

Accepted Answer

Mass is independent of gravity, while weight depends on gravity.

Question 10

If the net force on a cart on a level track is doubled, but the acceleration does not change, what is a possible explanation?

Accepted Answer

The mass of the cart doubled when the force doubled.

Question 11

When the string is pulled down quickly in the classic 'two strings and a hanging mass' demonstration, the bottom string breaks. This best illustrates the

Accepted Answer

mass of the ball.

Question 12

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 13

A 20 kg object weighs how much on Earth?

Accepted Answer

$$196\ \mathrm{N}$$

Question 14

Which of the following is true about the force of friction?

Accepted Answer

It can occur with sliding objects, in water, and in air.

Question 15

A 3 kg object is accelerated at $$7\ \mathrm{m/s^2$}. $$What is the net force acting on it?

Accepted Answer

$$21\ \mathrm{N}$$

Question 16

If you double the mass of an object but keep the net force the same, what happens to the acceleration?

Accepted Answer

It is halved.

Question 17

A 40 N object is weighed on Earth. What is its mass?

Accepted Answer

$$4.08\ \mathrm{kg}$$

Question 18

Which of the following best describes inertia?

Accepted Answer

The tendency of an object to resist changes in its motion.

Question 19

A 20 kg sled is pulled to the right with a 50 N force. If the force of friction is 10 N to the left, what is the acceleration?

Accepted Answer

$$2\ \mathrm{m/s^2$}$$

Question 20

Which of the following is a real-world example of Newton's Third Law?

Accepted Answer

A swimmer pushes water backward, and the water pushes the swimmer forward.

Newton's Laws of Motion and Forces: Study Notes

Guida di studio - Domande di pratica

Study guide - Flashcard