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Transfer of Heat: Temperature in Kelvins

  1. Nov 23, 2005 #1


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    A person's body is producing energy internally due to metabolic processes. If the body loses more energy than metabolic processes are generating, its temperature will drop. If the drop is severe, it can be life-threatening. Suppose a person is unclothed and energy is being lost via radiation from a body surface area of 1.24 m2, which has a temperature of 34 °C and an emissivity of 0.614. Suppose that metabolic processes are producing energy at a rate of 98.8 J/s. What is the temperature in Kelvin of the coldest room in which this person could stand and not experience a drop in body temperature?

    I used the formula Q= e*sigma*(T kelvins ^4) times(area) I get 384.21 after changing the temperature to 307.15 Kelvins. I am not sure where to place the rate of energy within this problem.
  2. jcsd
  3. Nov 23, 2005 #2


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    The Stefan-Boltzmann law is based on the radiative heat transfer between hot and cold - i.e. (TH4 - TC4).
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