Page 6 - Fair, Geyer, and Okun's Water and wastewater engineering : water supply and wastewater removal

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kWh

10 4 0.06242 lb/ft 3 /d 0.09294 ft candle

2.778 44.25 ft-lb/min 1.341 hp 3.412 Btu/h Customary Equivalents* 0.06242 lb/ft 3 1 ppm or mg/L 3.281 ft 3 /ft 2 /d 35.31 ft 3 /s 0.0353 ft 3 /s

1 J/s The density of water conditions is 1,000 or 1,000 g/L If this is converted should be expressed in mm/s (1mm/s 86.4 m 3 /m 2 /day).

1 watt Application of Units Comments under standard kg/m 3 or 1 g/mL. to a velocity, it

kJ W kW J/s Symbol kg/m 3 mg/L kg/m 3 /d m 3 /m 2 /d m 3 /s L/s lumen/m 2

kilojoule watt kilowatt joule per second Unit kilogram per cubic meter milligram per liter (water) kilogram per cubic meter per day meter cubic per square meter per day cubic meter or liter of free air per second lumen per square meter

Power Description Density Concentration BOD loading Hydraulic load per unit area, e.g., filtration rates Air supply Optical units

0.7375 lb-ft 23.73 poundal-ft 15,850 gpm 2,119 cfm or ft 3 /min 15.85 gpm Customary Equivalents* 35.31 ft 3 /s 15.85 gpm or gal/min 0.1835 gpm or gal/min 264.2 gal/year 0.2642 gpcd

The meter is mea- sured perpendicular to the line of action of the force N. Not a joule. Comments For meteorological purposes, it may be convenient to mea- sure precipitation in terms of mass/unit area (kg/m 2 ). 1 mm of rain 1 kg/m 2 86.4 m 3 /d 1 L/s

N.m m 3 /s L/s Application of Units Symbol mm m 3 /s L/s m 3 /d m 3 /year Lpcd *Miles are U.S. statute, qt and gal are U.S. liquid, and oz and lb are avoirdupois.

newton meter meter cubic per second liter per second Unit millimeter cubic meter per second liter per second meter cubic day per cubic meter per year liter per capita per day

Moment of torque Flow (volumetric) Description Percipitation, run-off, evaporation Flow Discharges or abstractions, yields Usage of water