Winter had arrived in Holland. Your car was outside and an icelayer has formed overnight on your front car window. The temperature inside and outside the car is -18C initially. The window has a thickness of 5,0 mm. Luckily the car has a defrost system and when starting your car, the system is blowing air of 29C on the interior surface. The icelayer on the outside behaves as an insulating layer. The properties of the car window are =2100 kg/m3, cp=800 J/kgK, and k =1.30 W/mK. You are looking for the interior convection coefficient that would allow the exterior surface to reach 0C in 50 s.

What is the energy rate balance (expressed in ) of the car window? Explain your answer