Physics-
General
Easy
Question
The temperature of the two outer surfaces of a composite slab, consisting of two materials having coefficients of thermal conductivity K and 2K and thickness x and 4x, respectively are T2 and T1 (T2 > T(a) . The rate of heat transfer through the slab, in a steady state is 
, with ¦ which equal to
- 1
The correct answer is:
Equation of thermal conductivity of the given combination 
. Hence rate of flow of heat through the given combination is 
=
On comparing it with given equation we get 
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