A composite wall consists of two plates A and B placed in series normal to the flow of heat. The thermal conductivities are k A and k B and the specific heat capacities are C PA and C PB for plates A and B respectively. Plate B has twice the thickness of plate A. At steady state, the temperature difference across plate A is greater than that across plate B, when

A composite wall consists of two plates A and B placed in series norma

1.	A composite wall consists of two plates A and B placed in series normal to the flow of heat. The thermal conductivities are k A and k B and the specific heat capacities are C PA and C PB for plates A and B respectively. Plate B has twice the thickness of plate A. At steady state, the temperature difference across plate A is greater than that across plate B, when
A.	C PA > C PB
B.	C PA < C PB
C.	k A < 0.5 k B
D.	k A >2 k B
Answer» D. k A >2 k B

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