$\Rightarrow \frac{A}{2}=A \sin 3 \omega$
$\Rightarrow \sin 3 \omega=\frac{1}{2}$
$\Rightarrow 3 \omega=\frac{\pi}{6}$
$\Rightarrow \omega=\frac{\pi}{18}=\frac{2 \pi}{T}$
$\Rightarrow T=36 \; s$

$y = A{e^{ - \frac{{bt}}{{2m}}}}\sin (\omega 't + \phi )$
where the symbols have their usual meanings. If a $2\ kg$ mass $(m)$ is attached to a spring of force constant $(K)$ $1250\ N/m$ , the period of the oscillation is $\left( {\pi /12} \right)s$ . The damping constant $‘b’$ has the value. ..... $kg/s$