As a heat transfer specialist for a large company in the mid-west, you have been asked to determine the power needed to maintain a 0.5 m2 surface at a prescribed temperature of 150 C. It is known that atmospheric air flows parallel to the flat surface (U∞ = 25 m/s, T∞ =20 C), and that the flow induces a drag force of 1N. What is the electrical power needed?