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Question
A body of mass m moving with a velocity v is acted upon by a force. Write an expression for change in momentum in each of the following cases: (i) When v << c, (ii) When v → c and (iii) When v << c but m does not remain constant. Here, c is the speed of light.
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Solution
(i) When v << c,
Δp = Δ(mv) = mΔv
(ii) When v → c,
Δp = Δ(mv)
(iii) When v<<c but m does not remain constant.
Δp = Δ(mv)
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