In: Physics
Heat from rain [5 pt]: The dissipative energy loss from drag force as rain falls from rain clouds deposits heat into the atmosphere, at a rate comparable to wind. In this problem, you’re going to compute the power generated by rain drag dissipation.
(a) Assume a 1 mm radius spherical droplet of rain falls 1 km through the atmosphere at a terminal speed of 1 m/s. Determine the power dissipated by drag force for one such rain drop. Assume a water density of 10 kg/m .
(b) During a heavy rain shower, 6 inches of rain accumulates in a 1 m2 area on the ground. What power is dissipated in the atmosphere by this rain? Hint: scale up from the power generated by 1 raindrop to the water contained in a 6 inch x 1 m2 volume. Compare your answer to solar power, which is roughly 250 W in a m2 area (Note: the quantity power/area with units N/m2 is known as flux).