A plane wall with constant properties is initially at a uniform temperature T0. Suddenly, the surface at x = L is exposed to a convection process with a fluid at T infinity (> T0) having a convection coefficient h. Also, suddenly the wall experiences a uniform internal volumetric heating q that is sufficiently large to induce a maximum steady-state temperature within the wall, which exceeds that of the fluid. The boundary at x = 0 remains at To.