3) Consider a large plane wall of thickness & 0.8 m. thermal conductivity k = 10 W/mC, and surface area A = 20 m². The left side of the wall at yis subjected to a net heat flux of - -120 W/m² while the temperature at that surface is measured to be 7 = 50°C. Assuming constant thermal conductivity and no heat generation in the wall: a) Express the differential equation and the boundary conditions for steady one-dimensional heat conduction through the wall. (5 marks) b) Obtain a relation for the variation of temperature in the wall by solving the differential equation. (10 marks) c) Evaluate the temperature of the right surface of the wall at y = -(5 marks) 4 =-120 W/m² T = 50°C A = 20m² 217 0.4m k = 10 W/ L=0.8m

Fig: 1