question_answer

A boy weighing 50 kg climbs up a vertical height of 100 m. Calculate the amount of work done by him. How much potential energy does he gain?

Answer:

                Given,   \[m=50\,\,kgh=100\,m\]                 \[W=?P.E.=?\] We know, Work done against gravity \[(W)=mgh\] \[W=50\times 9.8\times 100=49000\,J\] We also know that, \[P.E.=mgh\] \[P.E.=50\times 9.8\times 100=49000\,J\] \[\therefore \]the boy gains 49000 J of potential energy.