The air-conditioning system shown utilizes a 16-in diameter galvanized drainage pipe buried at a depth where the soil maintains the pipe surface at 60°f. air is forced through the pipe at a volumetric flow rate of 1200 cfm. the indoor air is maintained at a steady temperature of 72°f. if 63°f cooling air is desired, what length of pipe is required? what is the heat transfer? assume that the pipe has a roughness of 0.10 inch. how can the length of pipe be reduced and still achieve the same heat transfer?

Agas contained within a piston-cylinder assembly e end nation about same energy states, 1 and 2, where pi 10 bar, v undergoes two processes, a and b, between the sam 0.1 m3, ui-400 kj and p2 1 bar, v2 1.0 m2, u2 200 kj: process a: process from 1 to 2 during which the pressure- volume relation is pv constant process b: constant-volume process from state 1 to a pressure of 2 bar, followed by a linear pressure-volume process to +20 0 state 2 kinetic and potential energy effects can be ignored. for each of the processes a and b, (a) sketch the process on p-v coordinates, (b) evaluate the work, in kj, and (c) evaluate process the heat transfer, in kj