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 is

Options

A. `(4)/(3)K`
B. `(2)/(3)K`
C. `sqrt(3)K`
D. 3K

Answer

A

Explanation

In series, equivalent thermal conductivity
`K_(eq)=(2K_(1)K_(2))/(K_(1)+K_(2)) or, K_(eq)=(2xxK xx 2K)/(K+2K)=(4)/(3)K`