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

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SUMMARY

The rate of heat loss through an insulated wall using glass wool with a thermal conductivity of K = 0.046 W/m°C can be calculated using the formula Q = (K * A * ΔT) / L. For a wall area of 1.0 m by 1.5 m, insulated with a 20 cm thick layer of glass wool and a temperature difference of 20.0°C, the correct calculation yields a heat loss of 4.6 W. The initial error in calculation was due to incorrect area input, which was clarified during the discussion.

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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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