Question 1

A person pushes against a wall as shown in the first image. According to Newton's third law, what is the reaction force to the person's hand pushing on the wall?

Accepted Answer

The wall pushes back on the person's hand with an equal and opposite force.

Question 2

A hammer strikes a nail, as shown in the second image. Which statement best describes the forces involved?

Accepted Answer

The force of the hammer on the nail is equal in magnitude and opposite in direction to the force of the nail on the hammer.

Question 3

A rocket launches by expelling gas backward, as shown in the third image. According to Newton's third law, what is the reaction force?

Accepted Answer

The gas pushes the rocket forward with an equal and opposite force.

Question 4

A man pulls on a spring attached to a wall, as shown in the fourth image. What is the reaction force to the man's pull?

Accepted Answer

The spring pulls back on the man with an equal and opposite force.

Question 5

When a cannon fires a cannonball, as shown in the fifth image, what happens according to Newton's third law?

Accepted Answer

The cannon recoils backward with a force equal in magnitude and opposite in direction to the force on the cannonball.

Question 6

Which equation correctly expresses Newton's third law, as shown in the sixth image?

Accepted Answer

$$F_1$$ = -$$F_2$$

Question 7

A soccer player kicks a ball with a force of 1500 N. What is the magnitude of the force the ball exerts on the player's foot?

Accepted Answer

1500 N

Question 8

When you step off a curb, Earth pulls you downward. What is the reaction force?

Accepted Answer

You pull Earth upward with an equal force.

Question 9

A high-speed bus collides head-on with a flying bug. Which experiences the greater force during the collision?

Accepted Answer

Both experience the same magnitude of force.

Question 10

Two people of equal mass push off from each other on slippery ice. What happens?

Accepted Answer

Both move at the same speed in opposite directions.

Question 11

Why don't action and reaction forces cancel each other out?

Accepted Answer

They act on different objects.

Question 12

A block of ice slides down a friction-free ramp. As the slope increases, what happens to the normal force?

Accepted Answer

The normal force decreases.

Question 13

A skier stands on a slope as shown in the ninth image. Which component of the skier's weight propels them down the hill?

Accepted Answer

The component of weight parallel to the slope.

Question 14

A tossed stone's velocity is shown in the seventh image. Which statement is correct about its velocity components?

Accepted Answer

The vertical and horizontal components are perpendicular to each other.

Question 15

Which of the following best describes the process of resolving a vector?

Accepted Answer

Breaking a vector into perpendicular components.

Question 16

According to Newton's second law, what is the acceleration $$a of an $$object with net force $$F_{net}$$ and mass $$m$$?

Accepted Answer

$$a = \frac{F_{net}}{m}$$

Question 17

When a block is on a ramp that is raised to 90 degrees (vertical), what is the net force on the block?

Accepted Answer

The net force is equal to the block's weight, $$mg.$$

Question 18

Which of Newton's laws explains why a passenger moves forward in a car when it suddenly stops?

Accepted Answer

Newton's first law (law of inertia)

Question 19

A sled is pulled at an angle as shown in the eighth image. Which component of the pulling force moves the sled forward?

Accepted Answer

The horizontal component, $$F_x$$

Question 20

Which of the following is NOT a correct statement of Newton's third law?

Accepted Answer

Action and reaction forces always act on the same object.

Chapter 5 newtons third law

스터디 가이드 - 연습 문제

학습 가이드 - 플래시카드