Heat loss

  • Thread starter Revolt
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  • #1
Revolt
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Homework Statement



a person with a body temp of 37 degrees stands on snow with a temp of 0 degrees
each of there shoes has a sole 1cm thick with an area of 300cm^2 and a 0.2 thermal conductivity
what is the magnitude and direction of heat flow

Homework Equations





The Attempt at a Solution



right well obviously the direction is into the ground, heat travels from hot to cold

now I am not sure if you need to calculate the volume of "sole" which the heat is being conducted through or not and that has me stumped as its the first hurdle at which I am clueless!
 

Answers and Replies

  • #2
Doc Al
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What equation describes heat conduction?
 
  • #3
Revolt
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dQ/dt = -kA dT/dx

if a is the cross sectional area of the sole of the shoe do you then not need the thickness of it ? ;s and dT/dx would be the rate of change of temperature, however I am unsure as to what the rate of change is as all your told is it changes from 37 to 0

ive hit a brick wall with this one !
 
  • #4
Doc Al
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Instead of dT/dx, write it as [itex]\Delta T/\Delta x[/itex]. That's temperature difference over thickness.

For more, read Heat Conduction.
 

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