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A slab consists of two parallel layers o...

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

`K_1 +K_2`

B

`(K_1+K_2)/(2)`

C

`(2K_1K_2)/(K_1+K_2)`

D

`(K_1+K_2)/(2K_1K_2)`

Text Solution

Verified by Experts

The correct Answer is:
B
`K_(eq)=(K_1A_1+K_2A_2)/(A_1+A_2)=(K_1+K_2)/(2)` [as `A_1=A_2`]
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