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How fast would a body reach thermal equilibrium ?

  1. Jul 20, 2011 #1

    Edi

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    For example, I place a simple steel cube weighting 1 kg in a room [filled with air] at 20C [room temperature]. - how fast would the cube heat up to 20C (yes, actually equilibrium would be a bit lower than 20C, but lets.. imagine that is is a infinitely large room and .. yes, you get it ) ?
    Yes, I know that increasing surface area would increase the rate of energy exchange and moving air [wind] would speed up the process too.. but I dont know the exact figures and formulas.. :(
     
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  3. Jul 20, 2011 #2

    fluidistic

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    Gold Member

    I'd use Newton's law of cooling.
    [itex]\frac{dQ}{dt}=hA(T_{\text {room}}-T_{\text {cube} })[/itex] where A is the surface area of the cube and h is the heat transfer coefficient (depending on the material of the cube).
     
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