Keywords

Force

Something that makes a change happen

Magnitude

The value of a force in newtons

Scalar

Things that have magnitude but not direction

Vector

Things that have a magnitude and a direction- forces are always vectors

Contact force

Can only act when two things touch

Non contact force

Can act on things not touching

Balanced (forces)

When forces are equal and opposite each other also called equilibrium

Unbalanced (forces)

When opposing forces are not equal to each other

Resultant (force)

The overall force once all the forces are considered

Force arrows

Show direction and size of a force

Newton

Unit force is measured in

Newtonmeter

A spring calibrated so it has a scale to measure force

Centre of mass

A point in the middle of an object where all its mass acts

Elastic

A material that returns to its original shape after being deformed

Plastic

A material that does NOT return to its original shape after being deformed

Speed

Distance / time (scalar quantity)

Velocity

Distance (in a certain direction) / time (vector quantity)

Distance

How far an object moves (scalar quantity)

Displacement

The straight line distance from the start point to the end point (vector quantity)

Terminal velocity

The maximum speed reached when the forces are balanced