Q. The wheel of toy car rotates about axis. It slows down from 400 rps to 200 rps in 2s. Then its angular retardation in $rads^{- 2}$ is
A) 200 $\pi$
B) 100
C) 400 $\pi$
D) None of these
Explanation
(a) Given, $\omega_{1} = 2\pi \times 400$ rad $s^{- 1}$
$\omega_{2} = 2\pi \times 200$ rad $s^{- 1}$
$\therefore\alpha = \frac{2\pi(400 - 200)}{2} = 200\pi$ rad $s^{- 2}$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.