Air at 25 ° C blows over the hot steel plate whose surface temperature is maintained at 250 ° C. The plates are 50 cm x 40 cm in dimensions and 3 cm thick. The convection heat transfer coefficient on...

Air at 25 ° C blows over the hot steel plate whose surface temperature is maintained at 250 ° C. The plates are 50 cm x 40 cm in dimensions and 3 cm thick. The convection heat transfer coefficient on the upper surface is 30 W / (m? ° C). The thermal conductivity of steel is 45 W / (m ° C). Calculate the hourly heat loss from the plate surface. a. heat loss per hour = kJ. b. If the reverse side surface temperature is maintained, determine the hourly heat loss incurred = kJ.