Q 11-04-010NEETNEET 2021Top questionEasy
A ball of mass $0.15$ kg is dropped from a height $10$ m, strikes the ground and rebounds to the same height. The magnitude of impulse imparted to the ball is ($g = 10\ \text{m/s}^2$) nearly :
Answer: (C) $4.2$ kg m/s
Speed at impact: $v = \sqrt{2gh} = \sqrt{200} \approx 14.1$ m/s. It rebounds to the same height, so it leaves with the same speed upward.
$$J = m(v + v) = 0.15 \times 2 \times 14.1 \approx 4.2\ \text{kg m/s}$$
Solution by Sreeraj P, M.Sc Physics