Question

Calculate the velocity of the bob of a simple pendulum at its mean position if it is able to rise to a vertical height of 20 cm without loosing circular path anywhere. Given : g = 980 $cm{s}^{-2}$.

Answer 1

Kinetic energy of the bob at the mean position = Potential energy of the bob at the highest position.

$\frac{1}{2}m{v}^2$ = mgh

$v=\sqrt{2gh}$

$=\sqrt{2\times 9.8\times 0.20}$

$=1.97m/s$