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A composite wall of a furnace has two layers of equal thickness having thermal conductivities in the ratio 2:3. What is the ratio of the temperature drop across the two layers?

A composite wall of a furnace has two layers of equal thickness having thermal conductivities in the ratio 2:3. What is the ratio of the temperature drop across the two layers? Correct Answer 3:2

We know that temperature is inversely proportional to thermal conductivity, so the ratio is 2:3.

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