Q. A circular disc of mass 0.41 kg and radius 10 m rolls without slippling with a velocity of $2ms^{- 1}$. The total kinetic energy of disc is
A) 0.41 J
B) 1.23 J
C) 0.82 J
D) 2.45 J
Explanation
(b) $K = \frac{1}{2}\ mv^{2}\left( 1 + \frac{k^{2}}{R^{2}} \right)$
$= \frac{1}{2} \times 0.41 \times (2)^{2} \times \left( \frac{3}{2} \right)$
$= 1.23\ J$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.