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Question
Calculate the change in momentum of a body weighing 5 kg when its velocity decreases from 20 m/s to 0.20 m/s.
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Solution
For example,
Given that:
mass, m = 5 kg
velocity, v1 = 20 m/s
Therefore, momentum of a body moving with velocity v1, p1 = m × v1
= 5 × 20 = 100 kg.m/s
Now,
mass, m = 5 kg
velocity, v2 = 0.20 m/s
Therefore, momentum of a body moving with velocity v1, p2 = m × v1
= 5 × 0.20 = 1 kg.m/s
Change in the momentum of a body = p1 − p2
= 100 − 1
= 99 kg.m/s
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