Q. A solid cylinder on moving with constant speed $v_{0}$ reaches the bottom of an incline of 30${^\circ}$. A hollow cylinder of same mass and radius moving with the same constant speed $v_{0}$ reaches the bottom of a different incline of $\theta$. There is no slipping and both of them go through the same distance in the same time ; $\theta$ is then equal to

A) $37{^\circ}$
B) $30{^\circ}$
C) $42{^\circ}$
D) $45{^\circ}$
Explanation

(c) For solid cylinder, $\theta = 30{^\circ},\ K^{2} = \frac{1}{2}R^{2}$
For hollow cylinder, $\theta = ?,\ K^{2} = R^{2}$
Using we find,
$\frac{\left( 1 + \frac{1}{2} \right)}{\sin{30{^\circ}}} = \frac{1 + 1}{\sin\theta}$
$\therefore\ \sin\theta = \frac{2}{3} = 0.6667$
$\theta = 42{^\circ}$

Dr. Abubacker
Reviewed by Dr. Abubacker

Physics Educator & NEET/JEE Specialist

Ph.D. in Physics with 19+ years of teaching experience.