Question

A uniform semicircular ring of radius $R$,and mass $M$ is rotating about a vertical axis (passing through its circumference mid point) with angular velocity $\omega$ then its angular momentum is given as $\frac{8M{R}^2}{11k}\omega$ then the value of k is

Answer 1

MOI of semicircular ring about the given axis $=\frac{8m{R}^2}{11}$

$L=I\omega =\frac{8m{R}^2}{11}\omega =\frac{8m{R}^2}{11k}\omega =k=1$