Question #126a1

1 Answer
Nov 28, 2015

You can do it like this:

Explanation:

Hooke's Law tells us that force F is proportional to extension x:

:.F=-kx

k is the force constant.

x is the extension.

For a spring the work done in stretching it will be converted to stored elastic potential energy.

Work done = force x distance moved in the direction of the force.

With a spring we cannot use this directly since the force is constantly changing.

We need to use a bit of calculus:

W=intF.dx

:.W=-int_0^xkx.dx

:.W=1/2kx^2

This gives us the stored elastic potential energy.