The motion of a simple pendulum executing S.H.M. is represented by...

Comparing the given equation $y = Asin$\left(\pit + ϕ\right)$with a standard equation$y = Asin\left(\omegat + ϕ\right)$. We have</p><p>$\omega = \pi rad{s}^{- 1}$</p><p>Since time period is$T = \dfrac{2\pi}{\omega} = 2s$, it is a second's pendulum.</p><p>$T = 2\pi\sqrt{\dfrac{L}{g}} ⇒ L = \dfrac{g}{{\pi}^{2}} = 99 . 4cm