Potential

Potential in general may be treated as an attribute of a point in space, and may expre the potential energy which a unit ma would have if placed at that point. This conception of potential is that of a property attributable to a point in space, such that if a unit ma were placed there the forces acting upon it would supply the force factor of energy, while the body would supply the ma factor. This property is expre ible in units, which produce, if the supposed ma is a unit ma , units of work or energy, but potential itself is neither. Thus taking gravitation, a pound ma on the surface of the earth (a uming it to be a sphere of 4,000 miles radius) would require the expenditure of 21,120,000 foot pounds to remove it to an infinite distance against gravity. The potential of a point in space upon the surface of the earth is therefore negative and is represented by -21,120,000*32.2 foot poundals (32.2 = acceleration of gravity). (See Poundal.) In practice and conventionally all points on the earth's surface are taken as of zero potential. [Transcriber's note; 21,120,000 foot pounds is about 8 KWh.] 429   STANDARD ELECTRICAL DICTIONARY.