Solution: 1. Field Area: The field is given to be rectangular. Note that there are 43,560 ft2/acre. The irrigated area is the length of the mainline (1,320 ft) multiplied by twice the length of one lateral (2 x 600 ft): (1,320)(1,200)36.4 acres43,560=2. System Capacity: Use Eq. 5.4 and the given data: sAd(36.4)(1.9)Q453453373 gpmfT(7)(12)===3. Velocity Checks: Table 8.4: 5-inch aluminum pipe has an inside diameter of 4.900 inches (0.408 ft). Note that the maximum recommended velocity, in general, for sprinkler systems is 5 to 7 fps. 3(a). Full system capacity in the mainline: ssQ32Q4(373 gpm)V6A(60 s/min)(7.481gal/ft )(0.408 ft)===π.36 fps3(b). Half system capacity in the mainline: ssQ /232Q2(373 gpm)V32A(60 s/min)(7.481gal/ft )(0.408 ft)===π.18 fps3(c). Half system capacity through a hydrant valve: shydrant32Q2(373 gpm)V42A(60 s/min)(7.481gal/ft )(0.333 ft)===π.77 fpsAll of the above velocities are below 7 fps, so they are found to be acceptable.