==> $\frac{m}{k} = \frac{x}{g}$
==> $T = 2\pi \sqrt {\frac{m}{k}} = 2\pi \sqrt {\frac{x}{g}} $
$ = 2\pi \sqrt {\frac{{9.8 \times {{10}^{ - 2}}}}{{9.8}}} = \frac{{2\pi }}{{10}}\,sec$
$y = \frac{1}{{\sqrt a }}\,\sin \,\omega t \pm \frac{1}{{\sqrt b }}\,\cos \,\omega t$ will be
