Question

You have heard that covering your head is an excellent way to keep warm duirng cold days. Let’s model the head as a 17 diameter, 20 cm tall cylinder with a flat top. If the body’s surface temperature is 35 0C, what is the rate of heat loss from the top of the head only on a chilly 4 0C day? Assume all skin color regardless of color behaves like a black body in infrared where the radition loss occurs.