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Homework Help: Heat radiated from within a shell

  1. Mar 15, 2012 #1
    Why isn't ΔQ/Δt just P?

    Thank you!!

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  3. Mar 18, 2012 #2


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    In this problem, P is the total power generated within the entire planet. ΔQ/Δt is the rate of heat transfer through the surface of a sphere of radius r<R. In steady state, ΔQ/Δt must equal the power generated within a sphere of radius r, not within the entire planet.
  4. Mar 18, 2012 #3
    Thanks! :)
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