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)