Forces, motion and energy

1

What can a force change?

2

What unit is force measured in?

3

When an object is in motion, what direction does friction act in?

4

What are balanced forces?

5

What causes 'changing motion'?

6

What is Newton's Second Law?

7

Which statement best describes weight?

8

What unit is weight measured in?

9

What is the weight of an astronaut with a mass of 75 kg on the moon? The gravitational field strength on the moon is 1.6N kg^{-1}.

10

What unbalanced force is acting on an object that has a mass of 3 kg and is accelerating at 1.5\,m\,s^{-2}?

11

Compared to the force required to accelerate a 1 kg mass, what force would be required to produce the same acceleration in a 1000 kg mass?