KS3 Bitesize

Home > Science > Energy, electricity and forces > Forces

1.

Which of these is the best way to measure a force?

using a force meter

using a ruler

using a thermometer

2.

Forces can be:

pushes only

pulls only

pushes and pulls

3.

What is the unit of force called?

the newton, n

the newton, N

the neutron, N

4.

Why does an astronaut weigh less on the Moon than on the Earth?

the Moon has no atmosphere.

the Moon has no gravity.

the force of gravity is weaker on the surface of the Moon than on the surface of the Earth.

5.

What is the weight of a 20 kg box on the Earth?

2 N

20 N

200 N

6.

What is the pressure exerted by a man standing on one leg?

Half of the pressure he exerts when standing on two legs.

The same pressure as he exerts when standing on two legs.

Twice the pressure he exerts when standing on two legs.

7.

The weight of a 100 N laser printer is spread over 0.5m^{2}. What is the pressure it exerts?

50 N/m^{2}

200 N/m^{2}

500 N/m^{2}

8.

What can we say about the forces on an object that is not moving?

there must only be one force acting on it

the forces must be balanced

it must be very heavy

9.

The arrows in this diagram represent the sizes of forces acting on a stationary tennis ball. What will happen to the tennis ball?

it will stay still

it will start to move upwards

it will start to move downwards

10.

What happens to the air resistance on a car as the car goes faster?

it decreases

it stays the same

it increases

11.

A force of 4 N acts on a lever 2 m from the pivot. What is the moment?

8 Nm

6 Nm

2 Nm

12.

One way to increase the turning force on a spanner is to:

use a shorter spanner

use a longer pivot

use a longer spanner