Q.
A disc is rolling (without slipping) on a horizontal surface $C$ is its centre and $Q$ and $P$ are two points equidistant from $C$. Let $v_{P}$, $v_{Q}$ and $v_{C}$ be the magnitude of velocities of pints $P,\ Q$ and $C$ respectively, then
A) $v_{Q} > v_{C} > v_{P}$
B) $v_{Q} < v_{C} < v_{P}$
C) $v_{Q} = v_{P}$,$v_{C} = \frac{1}{2}v_{P}$
D) $v_{Q} < v_{C} > v_{P}$
Explanation
(a) In case of pure rolling bottommost point is the instantaneous centre of zero velocity.
[image:7_image160.emf]
Velocity of any point on the disc, $v = r\omega$,
where $r$ is distance of point from $O$.
$r_{Q} > r_{C} > r_{P}$
$\therefore$ $v_{Q} > v_{C} > v_{P}$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.