A large metal plate 10 cm thick is initially maintained at a temperature of 500°C. It is suddenly exposed to a surrounding at 140°C with a heat transfer coefficient of 570 W/m2K. At a later instant,...

A large metal plate 10 cm thick is initially maintained at a temperature of 500°C. It is suddenly exposed to a surrounding at 140°C with a heat transfer coefficient of 570 W/m2K. At a later instant, its centre plane reaches a temperature of 350°C. Find the temperature of a plane at a distance of 2.5 cm from the mid plane at the same instant. Take k = 170 W/mK, a = 4.78 x 10-5m2/s.