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Question
A body of mass 200 g is moving with a velocity of 5 ms−1. If the velocity of the body changes to 17 ms−1, calculate the change in linear momentum of the body.
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Solution
Mass of body = m = 200 g = 0.2 kg
Velocity = v1 = 5 ms−1; Velocity = v2 = 17 ms−1
Change in linear momentum of body
= mv2 – mv1= m (v2 – v1)
= 0.2(17-5)
= 2.4 Ns or kg ms−1
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