In the following figure, two insulating sheets with thermal resistances $R$ and $3R$ as shown in figure. The temperature $\theta$ is ...... $^oC$
Medium
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(d) For the two sheets $H_1 = H_2$ ($H =$ Rate of heat flow)
==> $\frac{{(100 - \theta )}}{R} = \frac{{(\theta - 20)}}{{3R}}$ ==> $\theta = 80°C$
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