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What is the correct answer?
4
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)
Correct Answer :
D. 2 k₁ k₂/ (k₁ + k₂)
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