(b) A wall of thickness 100 mm is insulated on one side and other side is exposed to 0C. Determine the wall temperature of the insulated surface if the internal heat generation in the wall is at the rate of 106 W/m. Take k = 40 W/mK. (5 marks] (c) A 12 cm diameter cylindrical bar initially at a uniform temperature of 400 C, is placed in a medium at 650 C with a convective coefficient of 22 W/mK. (1) Determine the time required for the center to reach 255C. [5 marks] (ii) Calculate temperature of the surface at this instant. [5 marks] Material k (W/m.K) p (kg/m3) 580 Cp (J/kg.K) Bar 0.620 1050