Rate will this student burn calories

AI Thread Summary
The discussion centers on calculating the rate at which a student will burn calories while sitting naked in a cold room. The student uses the formula dQ/dt = h.A.dT to determine the heat loss, but questions arise regarding the temperature values used in the calculations. There is confusion about whether the correct temperature should be 288.5 K or 285.5 K. Despite correcting the temperature, the student still arrives at an incorrect answer. The thread emphasizes the importance of accurate temperature values in thermodynamic calculations for calorie burning.
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rate will this student "burn" calories

Homework Statement


A student wants to lose some weight. He knows that rigorous aerobic activity uses about 700 kcal/h (2900 kJ/h) and that it takes about 2000 kcal per day (8400 kJ) just to support necessary biological functions, including keeping the body warm. He decides to burn calories faster simply by sitting naked in a 12.5° C room and letting his body radiate calories away. His body has a surface area of about 1.7 m2 and his skin temperature is 35° C. Assuming an emissivity of 1.0, at what rate will this student "burn" calories?


Homework Equations


dQ/dt=h.A.dT
1*1.7*295.5
=502.35 J/s

Why is my answer wrong?
 
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Is T not 288.5K ?
 


marcoskids said:
Is T not 288.5K ?

Sorry 285.5K
 


Yes your right but even with that I still get the wrong answer
 
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