A hollow sphere of inner radius of 30 mm and outer radius of 50 mm is electrically heated at inner surface with constant rate of 100 kW/m2. The outer surface is exposed to surroundings at 30°C. If h =...

A hollow sphere of inner radius of 30 mm and outer radius of 50 mm is electrically heated at inner surface with constant rate of 100 kW/m2. The outer surface is exposed to surroundings at 30°C. If h = 170 W/m2K and k = 20 W/mK, find temperature at inner and outer surface of the sphere.