Find the momentum of a body of mass 100 g having a kinetic energy of 20 J.

Kinetic energy, K.E. = 20 J (given);

Mass, m = 100 g = 0.1 kg (given)


And Momentum (p) =?


We know that, K.E. = 1/2 mv2


20 = 1/2 x 0.1 x v2


40 = 0.1 x v2


400 = v2


v = 20


Therefore, v=20m/s


Momentum (p) = mv


p = 0.1 kg x 20 m/s


p = 2 kg m/s


Therefore, momentum = 2kgm/s


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