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