Air at 20°c (1 atm) is flowing over a 5-cm diameter sphere with a velocity of 3.5 m/s. if the surface temperature of the sphere is constant at 80°c, determine (a) the average drag coefficient on the sphere and (b) the heat transfer rate from the sphere.

Air at a pressure of 1atm and a temperature of 40 c is in parallel flow over the top surface of a flat plate that is heated to a uniform temperature of 120 c. the plate has a length of 0.40m (in the flow direction) and a width of 0.15m. the reynolds number based on the plate length is 50, 000. what is the rate of heat transfer from the plate to the air? if the free stream velocity of the air is doubled and the pressure is increased to 10 atm what is the rate of heat transfer?