Question

A body of mass 10 kg is moving with a velocity of 20 m/s. The mass of the body is doubled and velocity is halved. Its initial kinetic energy is:
(a) 200 J
(b) 4000 J
(c) 2000 J
(d) 1000 J

April 17, 2024

Answer

2000 J

Reason — Given,

Initial velocity = 20 m/s.

Mass = 10 kg

Kinetic Energy = $1\over 2$ × m × v²

= $1\over 2$ × 10 × 20²

= 2000 J

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