Question

A rod of mass $m$ and length $l$ is connected with a light rod of length $l$. The composite rod is made to rotate with angular velocity $\omega$ is shown in the figure. Find the rotational kinetic energy.

Answer 1

Rotational kinetic energy of rod,
$K_{rotational}=\frac{1}{2}{I}_c{\omega }^2=\frac{1}{2}\left[\frac{m{l}^2}{12}\right]{\omega }^2=\frac{1}{24}m{\omega }^2{l}^2$.