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

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1.	A composite wall consists of two plates A and B placed in series normal to the flow of heat. The thermal conductivities are kA and kB and the specific heat capacities are CPA and CPB 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.	CPA > CPB
B.	CPA < CPB
C.	kA < 0.5kB
D.	kA>2 kB
Answer» D. kA>2 kB

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