A metallic sphere with a diameter of 10 mm, has an initial temperature of 500 C. It is cooled in ambient air at 25 C with convection heat transfer coefficient of h = 100 W/m2 C. What is its temperature after 1 minute? What is the amount of heat transfer during this time? Properties of sphere is given as: = 7833 kg/m3, k = 54 W/m C, cp = 0.465 kJ/kg C, and = 1.5 10-6 m2/s