A 15-cm × 15-cm circuit board dissipating 20 W of power uniformly is cooled by air, which approaches the circuit board at 20°C with a velocity of 6 m/s. Disregarding any heat transfer from the back surface of the board, determine the surface temperature of the electronic components

(a) At the leading edge

(b) At the end of the board. Assume the flow to be turbulent since the electronic components are expected to act as turbulators. For air properties evaluations assume a film temperature of 35°C. Is this a good assumption?