What will be the kinetic energy when momentum is 20%?

Hi Souvik, Momentum of a body is given by : P = mv P can be varied by varying either m or v. Since mass of a body is a constant quantity so we can change momentum of a body by changing its velocity. Momentum will be increased by 20% if the velocity is changed by 20%, since its a linear relation between the two. Let mass = m = 10kg velocity = v = 100m/s Momentum with these values = P = 1000 kgm/s K.E with these values = K.E = 50000 J After 20% increase velocity becomes = v' = 120m/s so new momentum = 1200 kgm/s Change in momentum = (1200-1000)/1000 x 100% = 0.2 x 100% = 20% New K.E = 72000 J Change in K.E = (72000 - 50000)/50000 x 100% = 0.44 x 100% = 44% Which agrees with the above result. All the best.

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