A composite rod has two sections of equal length and equal cross-section in good contact, well lagged at the sides. The conductivity of section 1 is three times that of section 2. The free end of sect

Question

A composite rod has two sections of equal length and equal cross-section in good contact, well lagged at the sides. The conductivity of section 1 is three times that of section 2. The free end of section 1 is at 9 0 ∘ C and the free end of section 2 is at 0 ∘ C. Find the temperature of the junction in ∘ C (one decimal).

TestHub · Accepted Answer

The heat current is the same, so L Δ T ​ ∝ K 1 ​ . The drops are in the ratio 3 1 ​ : 1 , so section 1 has 4 90 ​ = 22.5 and section 2 has 67.5 . The junction is at 90 − 22.5 = 67.5 ∘ C.

Physics - Heat & Thermo Question with Solution | TestHub

Doubts & Discussion