Physics

Question 1

What is Newton’s 1st Law?

Answer 1

An object at rest will stay at rest unless acted upon by an unbalanced force. An object in motion will stay in motion unless acted upon by an unbalanced force.

Question 2

What is Newton’s 2nd Law?

Answer 2

The acceleration of an object is directly related to the net force and mass of the object. F=ma

Question 3

Force equals _____

Answer 3

Mass times acceleration.

Question 4

Mass equals _____

Answer 4

Force divided by acceleration.

Question 5

Acceleration equals _____

Answer 5

Force divided by mass.

Question 6

Example of Newton’s 2nd Law

Answer 6

If you apply the same force to a truck and a tennis ball, the tennis ball will have a higher acceleration because it has the smallest mass out of the two.

Question 7

Example of Newton’s 1st Law

Answer 7

If you are sitting on a chair, you will forever stay in that position on the chair unless you or someone moves you. When you are driving, your body will keep moving in the same speed and direction as the car unless you hit something. If you hit something, your body will keep moving at the speed the car was previously moving until you hit something to stop you, e.g. the windscreen.

Question 8

What force is required to accelerate a 1000 kg spacecraft 4 m/s/s?

a. 4000 N
b. 250 N
c. 0.004 N
d. 1004 N

Answer 8

4000N

F = ma = 1000 x 4 = 4000 N.

Question 9

A small asteroid is accelerating towards Venus at 7.5 m/s/s under a gravitational force of 30 N. What is the asteroid’s mass?

a. 0.25 kg
b. 4 kg
c. 22.5 kg
d. 225 kg

Answer 9

4 kg

m = F / a = 30 / 7.5 = 4 kg.

Question 10

An astronaut – total mass with space-suit, 80 kg – is free-floating in space. She applies 400 N with her powerpack to move forward. How much does she accelerate?

a. 320 m/s/s
b. 32,000 m/s/s
c. 0.2 m/s/s
d. 5 m/s/s

Answer 10

5 m/s/s

a = F / m = 400 / 80 = 5 m/s/s.