A 50 KW electric furnace measure 1.2m x 1.0m x 0.8m. When the temperature inside  the furnace is 1520 oC, a block of aluminum with a mass of 300kg and a temperature  of 16.5oC is placed inside. Assuming the heat loss from the furnace walls is 500  Watts per m2 , how long will it take to heat the aluminum block to the furnace  temperature? Assume that the specific heat of aluminum is 0.9 KJ/kg-K.

6. a. The heat flux applied to the walls of the biomass combustion furnace is 20 W/m2. The furnace walls have a thickness of 10 mm and a thermal conductivity of 12 W/m.K. If the wall surface temperature is measured to be 50oC on the left and 30oC on the right, prove that conduction heat transfer occurs at a steady state!b. Heating the iron cylinder on the bottom side is done by placing the iron on the hotplate. This iron has a length of 20 cm. The surface temperature of the hotplate is set at 300oC while the top side of the iron is in contact with the still outside air. To reach the desired hotplate temperature, it takes 5 minutes. Then it takes 15 minutes to measure the temperature of the upper side of the iron cylinder at 300oC. Show 3 proofs that heat transfer occurs transiently

and finally find the volume rate in ft3/day

3. 100-gram oil at 20°C and 50-gram iron at 75 °C are placed in 200-gram iron container. The increase in temperature of the container is 5°C and the specific heat of oil is 0.43 cal/g °C. What is the specific heat of the iron?