A composite slab has two layers of different materials with thermal conductivities k₁ and k₂. If each layer has the same thickness, then the equivalent thermal conductivity of the slab will be

A composite slab has two layers of different materials with thermal c

1.	A composite slab has two layers of different materials with thermal conductivities k₁ and k₂. If each layer has the same thickness, then the equivalent thermal conductivity of the slab will be
A.	k₁ k₂
B.	(k₁ + k₂)
C.	(k₁ + k₂)/ k₁ k₂
D.	2 k₁ k₂/ (k₁ + k₂)
Answer» E.

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A composite slab has two layers of different materials with thermal conductivities k₁ and k₂. If each layer has the same thickness, then the equivalent thermal conductivity of the slab will be

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