A man of mass 60 Kg runs up a flight of 30 steps in 40 seconds. If each step is 20 cm high, calculate the power of the man.

Given,

Mass m= 60 kg


Number of steps = 30


Height of each step = 20 cm


Time taken= 40 s


Total height h = 20×30


= 600 cm


= 6m


Total time (t) = 40×30


= 1200 s


We know,



Work done = potential energy stored


= m × g × h


Let g = 10 ms-2


So, work done will be =60×10×6


=3600 J


Substituting value or work in above formula of power:



Power of man = 3 J/s


= 3 W


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