Mathematical Example: Power - QS Study
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A person of mass 70 kg can stair up 30 steps of 25 cm height each in 15 s. What is his power?

Here, Mass of the person, m = 70 kg

Force = Weight of the person = mg = 70 kg x 9.8 ms-2 = 686 N

Displacement, S = 35 x 25 cm = 750 cm = 7.5 m

Time, t = 15 s

Power, P = ?

We know, (g = 9 8 ms-2)

P = Work / Time = Fs / t

= (686N x 7.5m) / 15s

= 343 W

Ans: 343 W

Your work done will be, your weight x total height.

Your power will be, your total work done / total time i.e.,  (Work done / Total Time)