Problem 3. Heat transfer correlation Forced air at To = 25 C and velocity V = 10 m/s is used to cool electronic elements on a circuit board. One such element is a chip, 4 mm x 4 mm, located 120 mm from the leading edge of the board. Experiments have revealed that flow over the board is disturbed by the elements and that convection heat transfer is correlated by an expression of the form given below. Estimate the surface temperature of the chip if it is dissipating 30 mW. Use the following properties for air at 40C: P =1.02 kg/m, Cp = 1000 J/kg K, Pr= 0.70, v = 20.2x10m/s. (Ans: T. = 43.85 C] Nu, = 0.04 Res Pulls V.T. 1 = 4 mm Chip Board L = 120 mm