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Blackbody radiation problem

  1. Oct 4, 2010 #1
    Blackbody radiation problem!!

    1. The problem statement, all variables and given/known data
    The average person has 1.4 m^2 of skin at a skin temperature of roughly 306 K. Consider the average person to be an ideal radiator standing in a room at a temperature of 293 K.

    a.) Calculate the energy per second radiated by the average person in the form of blackbody radiation. Express you answer in watts. (How do I treat the temperature?)

    2. Relevant equations


    Where A = area; σ = Stefan-Boltzmann constant; T = temperature (in Kelvins).

    3. The attempt at a solution

  2. jcsd
  3. Oct 4, 2010 #2
    Re: Blackbody radiation problem!!

    The energy per second radiated will just be that equation with body temperature as T (~310 Kelvin); but note that this isn't the same as the total energy lost per second.
  4. Oct 23, 2010 #3
    Re: Blackbody radiation problem!!

    Energy radiated per unit time will be given by Stefan-Boltzman law -

    dQ/dt = eAσT^4 (σ - Stefan's constant)

    but here 'T' is to be taken in Kelvin and not degree celsius.

    and also this is not the energy lost since energy lost = (Energy radiated)-(Energy absorbed)

    put T value in the equation. For heat radiated T=306 and for absorbed T=293
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