Q 11-04-148JEE MainJEE Main 2022 (26 Jul, Shift 2)Easy
A ball of mass $0.15\ \text{kg}$ hits the wall with its initial speed of $12\ \text{m s}^{-1}$ and bounces back without changing its initial speed. If the force applied by the wall on the ball during the contact is $100\ \text{N}$, calculate the time duration of the contact of the ball with the wall.
Answer: (B) $0.036\ \text{s}$
$\Delta p = 2mv = 2\times0.15\times12 = 3.6\ \text{kg m s}^{-1}$, so $t = \dfrac{\Delta p}{F} = \dfrac{3.6}{100} = 0.036\ \text{s}$.
Solution by Sreeraj P, M.Sc Physics