In the square frame of side l of metallic rods, the corners A and C are maintained at T₁ and T₂ respectively. The rate of heat flow from A to C is ω. If A and D are instead maintained T₁ and T₂ respectively. Find the total rate of heat flow. Which of the following gives the correct final result?

Question

G1 Physics · Accepted Answer

In steady conduction, heat current is H=kAΔT/L. Treat each segment as a thermal resistance Rₜₕ=L/(kA); series resistances add and parallel heat currents add. Evaluating the given data/statements gives 4ω/3. Therefore the correct answer is A.