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Figure P5.53 shows data for a portion of the ducting in a ventilation system operating at steady state. Air flows through the ducts with negligible heat transfer with the surroundings, and the pressure is very nearly 1 atm throughout. Determine the temperature of the air at the exit, in F, and the exit diameter, in ft.

The electronic components of a computer consume 0.1 kW of electrical power. To prevent overheating, cooling air is supplied by a 25-W fan mounted at the inlet of the electronics enclosure. At steady state, air enters the fan at 20C, 1 bar and exits the electronics enclosure at 35C. There is no significant energy transfer by heat from the outer surface of the enclosure to the surroundings and the effects of kinetic and potential energy can be ignored. Determine the volumetric flow rate of the entering air, in m3 /s.