Q 11-06-106JEE MainJEE Main 2023 (31 Jan, Shift 1)Easy
A solid sphere of mass $1\ \text{kg}$ rolls without slipping on a plane surface. Its kinetic energy is $7\times10^{-3}\ \text{J}$. The speed of the centre of mass of the sphere is ______ $\text{cm s}^{-1}$.
Numerical value type. Enter your answer.
Answer: 10
For a rolling solid sphere $K=\dfrac7{10}mv^2$:
$$7\times10^{-3}=0.7\times1\times v^2\Rightarrow v=0.1\ \text{m s}^{-1}=10\ \text{cm s}^{-1}$$
Solution by Sreeraj P, M.Sc Physics