Prove that for finding the natural frequency of spring mass system, the mass of the spring can be taken in to account by adding one third of its mass of the main mass.

OR

P.T. $w_n = \sqrt{ \frac{k}{m + \frac{ms}{3}}}$

$\frac{\delta}{y} = \frac{x}{L}$

$\delta = (\frac{y}{L}) x$

$\delta' = …