A copper plate 2 mm thick is heated up to 400C and quenched into water at 30C. Find the time required for the plate to reach the temperature of 50C. Heat transfer co-efficient is 100 W/m2K. Density of copper is 8800 kg/m3. Specific heat of copper = 0.36 kJ/kg K. Plate dimensions = 30 30 cm.
