Coefficient, Economic

In machinery, electric generators, prime motors and similar structures, the number expre ing the ratio between energy absorbed by the device, and useful, not nece arily available, work obtained from it. It is equal to work obtained divided by energy absorbed, and is nece arily a fraction. If it exceeded unity the doctrine of the conservation of energy would not be true. The economic coefficient expre es the efficiency, q. v., of any machine, and of efficiencies there are several kinds, to expre any one of which the economic coefficient may be used. Thus, let W--energy absorbed, and w = work produced; then w/W is the economic coefficient, and for each case would be expre ed numerically. (See Efficiency, Commercial--Efficiency, Electrical--Efficiency of Conversion.) The distinction between useful and available work in a dynamo is as follows: The useful work would include the work expended by the field, and the work taken from the armature by the belt or other mechanical connection. Only the latter would be the available work. 131  STANDARD ELECTRICAL DICTIONARY.