Q7 of 19 Page 374

A boy of mass 80 kg is running at 10 m/s. Find the work done by him.

Work done = Kinetic Energy possessed by a body.

Kinetic Energy =


Given


Mass (m) = 80 Kg;


Velocity (v) = 10 m/s;


Kinetic Energy =


⇒ Kinetic Energy =


Hence the work done is 4000 J.


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