(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

While running up stairs at a (vertical) rate of 0.30 m/s, a man of 70 kg generates waste heat at a rate of 1300 J/s. What efficiency for the human body can you deduce from this?

2. Relevant equations

efficiency of heat engine=e=[itex]\frac{W}{Q_{1}}[/itex]=[itex]\frac{Q_{1}-Q_{2}}{Q_{2}}[/itex]=1-[itex]\frac{Q_{2}}{Q_{1}}[/itex]

3. The attempt at a solution

Kinetic energy= [itex]\frac{1}{2}[/itex](70)(.30)^{2}= 3.15

e[itex]\frac{3.15}{1300}[/itex]=0.0024 X 100=0.024 %

According to the book the answer is 14%

How do I get to this answer?

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# Homework Help: (21-23) thermodynamics problem. Finding efficiency for the human body

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