1.) Electric current flows through a flat steel plate that is 1 cm thick. Electrical power is dissipated via Joule heating of the plate. At steady state, the temperature distribution across the thickness of the plate is given by: TT(xx) = 2.5 K�1 − xx2 (0.5 cm)2� + 10 K � xx 0.5 cm� + 313 K The two surfaces of the plate are located at x = -0.5 cm and x = 0.5 cm.

The thermal conductivity of the plate is 50 W/m/K.

a. How much electric power is dissipated per unit area of the plate?

b. What are the values of heat flux at the two surfaces of the plate?

c. For each surface, is the heat flux directed toward or away from the surface?