What is the rate of heat loss through an insulated wall with glass wool?

AI Thread Summary
The discussion focuses on calculating the rate of heat loss through a wall insulated with glass wool, given its thermal conductivity of 0.046 W/m°C, a thickness of 20 cm, and a temperature difference of 20°C. The correct formula for heat loss is Q/deltaT = KA * delta T/L, where A is the area. The area was initially miscalculated, leading to incorrect results, but was later corrected to 1.0 m * 1.5 m. The final calculation confirmed the proper rate of heat loss, demonstrating the importance of accurate area measurement in thermal calculations. The conversation highlights common algebraic errors in physics problems and the significance of unit consistency.
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Homework Statement



A wall is insulated with glass wool of thermal conductivity K = 0.046 W/m oC. What is the rate of heat loss (in W) through an area 1.0 m wide by 1.5 m high, insulated with a layer of glass wool 20 cm (.2 m) thick, if the temperature difference across the layer is 20.0 oC?

Homework Equations



I think I'm just doing something wrong algebraically. I'm using Q/deltaT = KA * delta T/L

The Attempt at a Solution



Finding the area first (l*w?) = 1.0 m * .2m = .2m

Then

(0.046 * .2) * (20/.2) = .92 degrees
 
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Do your units match up?
 
I got it right :-) Sorry, I'm a noob. I was plugging in the wrong Area, and it was causing my number to come out wrong.

Thanks!
 
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