The figure shows the cross-section of the outer wall of a house buit in a hill-resort to keep the
Channel: Doubtnut
Date: 2020-04-05

The figure shows the cross-section of the outer wall of a house buit in a hill-resort to keep the house insulated from the freezing temperature of outside. The wall consists of teak wood of thickness `L_(1)` and brick of thickness `(L_(2) = 5L_(1))`, sandwitching two layers of an unknown material with identical thermal conductivites and thickness. The thermal conductivity of teak wood is `K_(1)` and that of brick is `(K_(2) = 5K)`. Heat conducion through the wall has reached a steady state with the temperature of three surfaces being known. `(T_(1) = 25^(@)C, T_(2) = 20^(@)C` and `T_(5) = - 20^(@)C)`. Find the interface temperature `T_(4)` and `T_(3)`.   src="https://d10lpgp6xz60nq.cloudfront.net/physics_images/RES_HAT_PHY_XI_C03_S01_003_Q01.png" width="80%