Q: A cart is pulled to the right with a force of 15 N and to the left with a force of 20 N. What is the net force and its direction?

$$5\ \text{N}$$\ \text{to the left}

Q: If two forces act on a box in opposite directions, one with 10 N to the right and one with 5 N to the left, what is the net force?

$$5\ \text{N}$$\ \text{to the right}

Question 1

According to Galileo's experiment at the Leaning Tower of Pisa, what happens when two objects of different weights are dropped simultaneously from the same height, assuming air resistance is negligible?

Accepted Answer

Both objects land at the same time.

Question 2

Which of the following best describes Newton's First Law of Motion?

Accepted Answer

Objects remain at rest or in uniform motion unless acted upon by a nonzero net force.

Question 3

A ball rolls down an inclined plane, then up another. According to Galileo, what happens to its speed as it moves up the second incline?

Accepted Answer

Its speed decreases.

Question 4

If two forces of 5 N each are applied to a box in the same direction, what is the net force?

Accepted Answer

$$10\ 	ext{N}$$

Question 5

A cart is pulled to the right with a force of 15 N and to the left with a force of 20 N. What is the net force and its direction?

Accepted Answer

$$5\ 	ext{N}$$\ 	ext{to the left}

Question 6

Which of the following is a vector quantity?

Accepted Answer

Force

Question 7

If a box is acted upon by a 30 N force upward and a 40 N force to the right, what is the magnitude of the resultant force?

Accepted Answer

$$50\ 	ext{N}$$

Question 8

What is the equilibrium rule in terms of forces?

Accepted Answer

$$\sum F = 0$$

Question 9

When you stand with one foot on each of two bathroom scales and your weight is evenly distributed, what does each scale read?

Accepted Answer

Half your weight

Question 10

A crate is pushed at a steady speed in a straight line. If the friction force is 75 N, how much force is your pushing force?

Accepted Answer

Equal to 75 N

Question 11

A bowling ball is in equilibrium when it:

Accepted Answer

Both of the above

Question 12

Which force is always perpendicular to the surface of contact?

Accepted Answer

Normal force

Question 13

If you toss a coin straight upward while riding in a vehicle moving at constant speed, where will the coin land?

Accepted Answer

In your hand

Question 14

Which scenario best illustrates dynamic equilibrium?

Accepted Answer

A car moving at constant speed in a straight line

Question 15

Which of the following is NOT a scalar quantity?

Accepted Answer

Velocity

Question 16

If the net force on an object is zero, what can be said about its motion?

Accepted Answer

It is either at rest or moving at constant velocity.

Question 17

Which of the following best describes inertia?

Accepted Answer

The tendency of an object to resist changes in motion.

Question 18

If two forces act on a box in opposite directions, one with 10 N to the right and one with 5 N to the left, what is the net force?

Accepted Answer

$$5\ 	ext{N}$$\ 	ext{to the right}

Question 19

Which of the following is NOT required for an object to be in equilibrium?

Accepted Answer

The object must be accelerating.

Question 20

A person pushes a box with a force of 75 N, and the box moves at constant speed. What is the force of friction acting on the box?

Accepted Answer

$$75\ 	ext{N}$$

chapter 2 newtons first law

스터디 가이드 - 연습 문제

학습 가이드 - 플래시카드