Two plates of same thickness of coefficients of thermal conductivities $K_1$ and $K_2$ and areas of cross section $A_1$ and $A_2$ are connected as shown. The effective coefficient of thermal conductivity $K$.
Two plates of same thickness of coefficients of thermal conductivities $K_1$ and $K_2$ and areas of cross section $A_1$ and $A_2$ are connected as shown. The effective coefficient of thermal conductivity $K$.
- A
$K_1A_1 + K_2A_2$
- B
$\frac{{{K_1}{A_1} + {K_2}{A_2}}}{{{A_1} + {A_2}}}$
- C
$\frac{{{K_1}{A_2} + {K_2}{A_1}}}{{{A_1} + {A_2}}}$
- D
$\frac{{{K_1}{A_1}}}{{{K_2}{A_2}}}$
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