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Let us assume two walls of same thickness and cross-sectional area having thermal conductivities in the ratio 1/2. Let us say there is same temperature difference across the wall faces, the ratio of heat flow will be

Let us assume two walls of same thickness and cross-sectional area having thermal conductivities in the ratio 1/2. Let us say there is same temperature difference across the wall faces, the ratio of heat flow will be Correct Answer 1/2

Q1 = k1 A1 d t1/δ1 and Q2 = k2A2 d t2/δ 2 Now, δ1 = δ2 and A1 = A2 and d t1 = d t2 So, Q1/Q2 = ½.

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