Two plates of same thickness, of coefficients of thermal conductivity $K_{1}\ and\ K_{2}$ and areas of cross section $A_{1}\ and\ A_{2}$ are connected as shown in figure. The common coefficient of thermal conductivity $K$ will be [image:11_image5.jpeg]

Question

Dr. Abubacker · Accepted Answer

(c) As is clear from figure.
$\frac{dQ}{dt} = \frac{dQ_{1}}{dt} + \frac{dQ_{2}}{dt}$
$\frac{K\left( A_{1} + A_{2} \right)dT}{dx} = K_{1}A_{1}\frac{dT}{dx} + K_{2}A_{2}\frac{dT}{dx}$
$K = \ \frac{K_{1}A_{1} + K_{2}A_{2}}{A_{1} + A_{2}}$

Q. Two plates of same thickness, of coefficients of thermal conductivity $K_{1}\ and\ K_{2}$ and areas of cross section $A_{1}\ and\ A_{2}$ are connected as shown in figure. The common coefficient of thermal conductivity $K$ will be

Explanation

Reviewed by Dr. Abubacker

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