Physics · 2021
JEE Main · 26 February 2021, Shift 1 · Q9
The temperature θ at the junction of two insulating sheets, having thermal resistances R_1 and R_2 as well as top and bottom temperatures θ_1 and θ_2…
The temperature $\displaystyle \theta$ at the junction of two insulating sheets, having thermal resistances $\displaystyle \mathrm{R}_1$ and $\displaystyle \mathrm{R}_2$ as well as top and bottom temperatures $\displaystyle \theta_1$ and $\displaystyle \theta_2$ (as shown in figure) is given by :
Official answer
(1)
$\displaystyle \frac{\theta_1 R_2+\theta_2 R_1}{R_1+R_2}$
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JEE Main 2021 Physics question, with the answer from NTA’s final answer key. Where our answers come from.