Engineering Board Exam Reviewer · Thermodynamics · medium
A plane wall 0.2 m thick with a thermal conductivity of 0.8 W/m· K has an area of 10 m2. If the temperature difference across it is 25 °C, what is the rate of heat conduction?
- 100 W
- 40 W
- 4000 W
- 1000 W
Answer
D. 1000 W
Solution
q = kA T/L = 0.8(10)(25)/0.2 = 1000 W.
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