Question

How much work is needed to be done on a ball of mass 50 g to give it a momentum of 5 kg m s^-1?

April 23, 2024

Answer

mass = 50 g = 0.05 kg

momentum = 5 kg m s^-1

KE = momentum² / 2 × mass

Work done = KE = momentum² / 2 × mass

= $5^2\over 2 × 0.05$

= $25\over 0.01$ = 250 J

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