A slab consists of two parallel layers of two different materials of same thickness having thermal conductivities K_(1) and K_(2), the equivalent conductivity of the combination is :

A slab consists of two parallel layers of two different materials of s

1.	A slab consists of two parallel layers of two different materials of same thickness having thermal conductivities K_(1) and K_(2), the equivalent conductivity of the combination is :
Answer» `2/3K` `SQRT(2)K` `3K` `(4)/(3)K`. Solution :In seires `k_(s)(2k_(1)k_(2))/(k_(1)+k_(2))=(2k2k)/(k+2k)=(4)/(3)k`. CORRECT choice is (d).

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A slab consists of two parallel layers of two different materials of same thickness having thermal conductivities K_(1) and K_(2), the equivalent conductivity of the combination is :

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