Forced air at t[infinity] = 25°c and v = 10 m/s is used to cool electronic elements on a circuit board. one such element is a chip, 4 mm × 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

Aseries piping system conveys methyl alcohol. the system consists of 70 m of 1- nominal pipe follow by 50 m of 2-nominal pipe, both schedule 40 commercial steel. the 1-nominal pipe contains 3 90° elbows (regular) anda fully open gate valve, all threaded. the pressure drop through the system is 150 kpa. determine the volume flow rate through the system that is horizontally laid.