Physics · PYQ NEET UG 2025
हिन्दीA ball of mass \( 0.5\text{ kg} \) is dropped from a height of \( 40\text{ m} \). The ball hits the ground and rises to a height of \( 10\text{ m} \). The impulse imparted to the ball during its collision with the ground is (Take \( g = 9.8\text{ m/s}^2 \))
Correct answer · Option 1
\( 21\text{ NS} \)
Explanation
Velocity before impact \( v_1 = \sqrt{2gh_1} = \sqrt{2 \times 9.8 \times 40} = 28\text{ m/s} \). Velocity after impact \( v_2 = \sqrt{2gh_2} = \sqrt{2 \times 9.8 \times 10} = 14\text{ m/s} \). Impulse \( J = m(v_1 + v_2) = 0.5(28 + 14) = 21\text{ Ns} \).