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 m/s^2) nearly :

1. 0 kg m/s

2. 4.2 kg m/s

3. 2.1 kg m/s

4. 1.4 kg m/s

Doubtly Asked 30 Oct 2026 NEET UG 2021 Practice test neet Save WhatsApp Report

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Answer: 2. 4.2 kg m/s

Key idea: impulse equals change in momentum; the velocity reverses.

Speed at the ground \(v=\sqrt{2gh}=\sqrt{200}\approx14.1\) m/s. Rebounding to the same height means the same speed upward.

\(J=m(v-(-v))=2mv=2\times0.15\times14.1\approx4.2\) kg m/s. Option 2.

Doubtly AI · 30 Oct 2026 AI-generated · not yet verified Report

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