The human heart does 1.5 J of work in every beat. How many times per minute does it beat, if its power is 2 W?
Given, power, A = 2 W, time, / = 1 min = 60 s Total work, W = Pt
= 2 X 60 s = 120 J
V 1.5 J work is done in 1 beat.
.’. 120 J work will be done in 1.5 J= 80 beats
Therefore, number of beats per min = 80