Q. A solid sphere is in rolling motion. In rolling motion a body possesses translational kinetic energy ($K_t$) as well as rotational kinetic energy ($K_r$) simultaneously. The ratio $K_t : (K_t + K_r)$ for the sphere is
A) 10 : 7
B) 5 : 7
C) 7 : 10
D) 2 : 5
Explanation
[Solution] $K_r = \frac{2}{5}K_t$, so $K_t : (K_t + K_r) = 1 : \frac{7}{5} = 5 : 7$. Answer (2).
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.