Supports Unit 3e of the QCA scheme of work - Magnets and Springs

Forces are needed to move something.

When the forces are balanced there is no movement.

When a force is applied to a spring in a certain way, internal forces resist the applied force, keeping the spring balanced.

A leaf spring (above) is usually a blade of metal that is designed to bend.

This one is held at one end with the other end free. A load (force) is applied to the free end. When the load is applied the spring changes shape (moves) until the internal forces match the applied load, at which time it becomes stationary; movement stops because the forces are balanced.