Question

A body of mass 60 kg has the momentum of 3000 kg-m s^-1.
Calculate:
(i) the kinetic energy and
(ii) the speed of the body.

April 23, 2024

Answer

Mass = 60 kg

Momentum = 3000 kg m s^-1

(a) Kinetic Energy = $momentum^2\over 2 × mass$

= $3000^2\over 2 × 60$

= $3000^2\over 120$

= $3000 × 3000\over 120$

= 75000 J

(b) Momentum = mass × velocity

Velocity = $3000\over 60$ = 50 m s^-1

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