Rate will this student burn calories

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Homework Help Overview

The problem involves calculating the rate at which a student will "burn" calories while sitting in a cold room, taking into account factors such as body surface area, skin temperature, and room temperature. The context is related to thermodynamics and heat transfer.

Discussion Character

  • Exploratory, Assumption checking, Mathematical reasoning

Approaches and Questions Raised

  • The original poster attempts to apply the heat transfer equation to determine the calorie burn rate but questions the correctness of their calculations. Some participants question the temperature values used in the calculations.

Discussion Status

The discussion is ongoing, with participants exploring different temperature values and their impact on the calculations. There is no explicit consensus on the correct approach or answer yet.

Contextual Notes

Participants are discussing potential errors in temperature conversions and the implications for the calculations, indicating a need for clarity on the assumptions made regarding temperature and emissivity.

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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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