Q.
The instantaneous velocity of a point $B$ of the given rod of length 0.5 m is 3 ${ms}^{- 1}$ in the represented direction. The angular velocity of the rod for minimum velocity of end A is
A) 1.5 ${rads}^{- 1}$
B) 5.2 ${rads}^{- 1}$
C) 2.5 ${rads}^{- 1}$
D) None of these
Explanation
(b) If rod is rotated about end $A$, then vertical component of velocity $v_{\bot}$ of end $A$ will be zero.
$\therefore$ $\omega = \frac{v\cos{60{^\circ}}}{l} = \frac{\sqrt{3}v}{2l}$
$= \frac{\sqrt{3} \times 3}{2 \times 0.5} = 5.2\ rads^{- 1}$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.