Bending and Stretching

Elastic Objects return to their orignal shape when the forces are removed.

Inelastic objects keep their new shape when the forces are removed.

The point after which it will no longer return to its orignal shape is called the elastic limit

The spring constant for a spring is the force need to produce an extension of 1 metre. The bigger the spring constant, the more force is needed. 

Force = spring constant ✕ extension

F= kx

This equation is called Hooke’s Law. It works when objects are deforming elastically

It requires energy to stretch a spring and once it is stretched it stores energy 

Elastic potential energy = ½ x k x

More energy is used to load a rubber band that is released when the band is unloaded. This is because energy is stored in the band as thermal energy