# Simple Harmonic Motion - Springs

## Key Questions

• Simple harmonic motion is defined as an oscillatory motion where displacement occurs against the direction of a force acting and that force is proportional to the one degree power of displacement.

That means, $F = - k x$ where, $k$ is a constant

Here, $F$ is the force acting and $x$ is the displacement.

In case of spring,if we compress it by $x$ due to its elastic recoil,restoring force generated is $F = K x$ where,$K$ is the spring constant!

Now,this restoring force tries to return back the original length of the spring,i.e it acts against the direction of displacement caused to it.

So,the force-displacement relationship turns out to be,

$F = - K x$

Now,you can compare it with equation of S.H.M i.e $F = - k x$

So,here, $k = K$ i.e the spring constant.

Thereby simple spring motion fulfills the required criteria of being an S.H.M.