[Force] [Magnets] [Friction] [Gravity and Upthrust]

A force is any kind of PUSH or PULL.

Examples of actions that need a force:

  • pushing a toy car to make it move
  • squashing some modelling clay
  • hitting a cricket ball
  • bending a stick

Forces are needed to do the following:

  • to start and stop objects moving
  • to make objects change direction
  • to make objects change shape


Forces cause movement


Forces work in pairs

tug_of_war If the two pulling forces are equal the teams do not move

When one force is greater the teams move towards the larger force

Equal forces = no change in movement

Unequal forces = movement



Measuring Force

The unit of force is the newton (N).

Forces can be measured using a spring balance

Using a spring balance to measure the pull of gravity

(A spring balance is sometimes called a force meter or Newton meter)

Types of Force

Some forces have special names:

  • Magnetism: The pull or push produced by a magnet
  • Gravity: The force that gives us weight. Gravity always pulls downwards
  • Friction: A force that slows things down
  • Upthrust: A force that makes things float

(click on each force to find out more about it)