A composite flat wall of a furnace is made of two materials 'A' and 'B'. The thermal conductivity of 'A' is twice of that of material 'B', while the thickness of layer of 'A' is half that of B. If the temperature at the two sides of the wall are 400 and 1200°K, then the temperature drop (in °K) across the layer of material 'A' is (A) 125 (B) 133 (C) 150 (D) 160

A composite flat wall of a furnace is made of two materials 'A' and 'B'.
The thermal conductivity of 'A' is twice of that of material 'B', while the
thickness of layer of 'A' is half that of B. If the temperature at the two sides
of the wall are 400 and 1200°K, then the temperature drop (in °K) across
the layer of material 'A' is
(A) 125
(B) 133
(C) 150
(D) 160
by

1 Answer

Answer :

(D) 160
by

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