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Question
The average work done by a human heart while it beats once is 0.5 J. Calculate the power used by heart if it beats 72 times in a minute.
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Solution
P = `(W.D)/"time"`
W.D in 1 heartbeat = 0.5 J
W.D in 72 heartbeats = 0.5 × 72 = 36 J
Time = 1 minute = 60s
∴ P = `(WD)/t = 36/60 = 6/10` = 0.6 W
As a result, the power consumed by the heart is 0.6 W.
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