Two isolated systems with different temperatures are connected via a long square Steel rod. The Steel rod conducts heat between the two systems at a rate of 12 cal/s.

Question

Two isolated systems with different temperatures are connected via a long square Steel rod. The Steel rod conducts heat between the two systems at a rate of 12 cal/s. What will happen to the rate of the heat flow, if the length of the Steel rod is elongated thrice the original distance as well as halving the circular cross-sectional width?

Answer 1

I find this equation for the heat flow by conduction: Q/t = k A ΔT / L. The changes would result in Q/t = k (A/2) ΔT / (3L) = k A ΔT / 6L, hence 12 cal/s would be reduced to 2 cal/s.