Coil Spring

Key Stage 3

A Coil Spring is a metal wire bent into a spiral shape.

Springs obey Hooke's Law.

Springs can be extended and compressed.

Springs need two opposing forces to change length.


The spring will stretch to a certain length and then stay the same due to two opposing forces.

If one force were bigger than the other the spring would accelerate rather than stretch.

When a spring is oscillating up and down it has three important positions:

Compressed is when the spring is at its shortest.

Equilibrium is the length that the spring rests when it is not moving.

Extended is when the spring is stretched to its longest.


As the spring extends from equilibrium, energy is transferred from the kinetic energy store to the elastic potential energy store.	As the spring returns from stretched to equilibrium, energy is transferred from the elastic potential energy store to the kinetic energy store.

As the spring is compressed from equilibrium, energy is transferred from the kinetic energy store to the gravitational potential energy store.	As the spring returns from compressed to equilibrium, energy is transferred from the gravitational potential energy store to the kinetic energy store.