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Homework Help: Rate will this student burn calories

  1. Dec 7, 2011 #1
    rate will this student "burn" calories

    1. The problem statement, all variables and given/known data
    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?


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

    Why is my answer wrong?
     
  2. jcsd
  3. Dec 7, 2011 #2
    Re: rate will this student "burn" calories

    Is T not 288.5K ?
     
  4. Dec 7, 2011 #3
    Re: rate will this student "burn" calories

    Sorry 285.5K
     
  5. Dec 8, 2011 #4
    Re: rate will this student "burn" calories

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