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posted by  Rasputant on 12/9/2007 2:31:46 PM  |  status: Closed  

Energy Lost Question

Course Textbook Chapter Problem
Classical Physics Physics: Principles with Applications (6th) by Giancoli 14 N/A
Question Details:
For some reason I can't get my head around this problem.  Any help is appreciated, thanks in advance.
 
In the figure (not to scale) a special wall has three metal studs with conductivity of 463 W/m·K. The wall otherwise has a conductivity of 1.32 W/m·K. What is the energy loss per second to the nearest watt if the temperature difference across the wall is 25 Co?
 
 

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posted by physics is phun! on 1/3/2008 12:51:06 PM  |  status: Live
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Rasputant's comment:
"Thanks!!! I had that exact formula, but must've calculated it wrong."
Response Details:
well, you need to use this formula:
 
   ALSO  SEEN  AS:
 
H = rate of heat transfer
t = time (seconds)
A = Area of wall
Delta T = Change in temperature in Kalvin.  To convert Celcius to K, add 273.15 to the Celcius temp.
L = Thickness of the wall
 
     The temp in Kalvin is 298.15 b/c 25 + 273.15 = 298.15K
 
   YOU  ANSWER  IS  41413035 Watts per second
 
 
I hope this helps you a little.  Please let me know!
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