Retardation of Phase.
The fractional lagging behind of waves or alternating currents; by
lagging behind a portion of a wave length the corresponding phases, as
of full amplitude, are kept back or retarded. The phase of current
intensity may be retarded with reference to the electro-motive force by
the introduction of transformers of high capacity with high resistance
on open secondary circuits.
[Transcriber's note: Capacitors are used to correct current phase lag.]
Retentivity.
Coercitive or coercive force; by virtue of which steel retains its
magnetism. It is the more modern name, "coercive force" as a term being
rejected by many.
Synonyms--Coercive Force--Coercitive Force.
Retort Carbon.
Carbon deposited in coal gas retorts from decomposition of the
hydrocarbons. It is a very hard, pure form, and is of graphitic
modification. Owing to its great hardness it is little used for
electrical purposes, the molded carbons being easier to make. The
deposition occurs in the regular gas-making process, and is a
disadvantage to the working.
Return.
A line or conductor which is supposed to carry current back to its
starting point, after it has traversed a line. It may be a wire or the
grounding of the ends of a line [or] may make the earth act as a return,
termed ground- or earth-return. The best distinction of a return is to
so term the portion of a circuit on which no apparatus is placed.
Reversibility.
The principal in virtue of which a device for producing a given form of
energy can absorb the same and do work. The reversibility of the dynamo
is its quality in virtue of which it can act as a current generator,
thereby converting mechanical energy into electric energy, or if a
current is passed through it, it rotates, doing work, and thereby
converting electric energy into mechanical energy. The knowledge of this
principle can be traced back to Jacobi in 1850.
Reversible Bridge.
A form of Wheatstone's Bridge adapted for reversal of the positions or
interchange of the proportionate arms, v., so that the accuracy of the
coils can be tested.
Rheochord.
An apparatus by means of which variable quantities of wire are thrown
into the circuit; a rheostat using wire. (See Rheostat, Wheatstone's.)
Rheometer.
A galvanometer. (Obsolete.)