
Heat flow rate will be same through both
∴R1θ1−θ=R2θ−θ2
R2θ1−R2θ=R1θ−R1θ2
θ=R1+R2R2θ1+R1θ2
JEE Main 2021 — Physics Thermodynamics
The temperature θ at the junction of two insulating sheets, having thermal resistances R1 and R2 as well as top and bottom temperatures θ1 and θ2 (as shown in figure) is given by :

Held on 26 Feb 2021 · Verified 6 Jul 2026.
R2−R1θ1R2−θ2R1
R2−R1θ2R2−θ1R1
R1+R2θ1R2+θ2R1
R1+R2θ1R1+θ2R2
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