==> $\frac{a}{{\sqrt 2 }} = a\sin \frac{{2\pi }}{T} \cdot t$
==> $\sin \frac{{2\pi }}{T}t = \frac{1}{{\sqrt 2 }} = \sin \frac{\pi }{4}$
==> $\frac{{2\pi }}{T}t = \frac{\pi }{4}$
==> $t = \frac{T}{8}$
$2\,\frac{{{d^2}x}}{{d{t^2}}} + 32x = 0$
where $x$ is the displacement from the mean position of rest. The period of its oscillation (in seconds) is
