A cooking oven has a top surface temperature of 45 C when exposed to still air. At this condition the inside oven temperature and room air temperature are 180 and 20 C, respectively, and heat is...

A cooking oven has a top surface temperature of 45C when exposed to still air. At this condition the inside oven temperature and room air temperature are 180 and 20C, respectively, and heat is transferred from the top surface at 40 W. To reduce the surface temperature, as required by safety regulations, room air is blown across the top with a velocity of 20 m/s. Conditions inside the oven may be considered unchanged.

a. What will be the rate of heat loss under this new operating condition?

b. What will be the top surface temperature?