Question

A house is built with brick walls of thickness t = 30 cm (only solid stone, no air gap). The
thermal conductivity of brick is k= 0.8J/s/m/K

We consider a room with an outer wall
area A = 2.5 × 8 m2

Answer 1

Derive an equation for the inward heat flow J through this wall when the indoor temperature is Ti = 20 ◦C and the outdoor temperature To = 0 ◦C.

Answer 2

\[J = \frac{\kappa A (T_o - T_i)}{t}\]