Question

A man pulls a bucket of water of mass 10kg from a well 5meter deep in 5 sec. Calculate the power of the man.

Answer 1

Power = Work Done / Time
Work Done = Change in Potential Energy

Change in Potential Energy = mgh

Therefore,

Power = mgh/t
= 10*5*9.8/5
= 98 W

Answer 2

Here,m=10kg
h=5meter
t=5sec
g=10m/s

and,since P=(m×g×h)÷t
(10×10×10)÷5
=100