Consider a compound slab consisting of two different material having equal thickness and thermal conductivities `K` and `2K` respectively. The equivalent thermal conductivity of the slab isA. `2/3 K`B. `sqrt(2) K`C. `3 K`D. `4/3 K`

Consider a compound slab consisting of two different material having e

1.	Consider a compound slab consisting of two different material having equal thickness and thermal conductivities `K` and `2K` respectively. The equivalent thermal conductivity of the slab isA. `2/3 K`B. `sqrt(2) K`C. `3 K`D. `4/3 K`
Answer» Correct Answer - D The equivalent thermal conductivity when the slabs are connected in series is `K_(eq) = (sumx_(n))/((sumx_(n))/(sumK_(n)))= (x+x)/(x/K+x/(2K)) = (2x(2K^(2)))/((2Kx+Kx))=4/3 K`

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Consider a compound slab consisting of two different material having equal thickness and thermal conductivities `K` and `2K` respectively. The equivalent thermal conductivity of the slab isA. `2/3 K`B. `sqrt(2) K`C. `3 K`D. `4/3 K`

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