Stress, Dielectric.
The condition of a dielectric when maintaining a charge; its two
extremities are in opposite states of polarity, or are under permanent
potential difference. As the two opposite polarities tend to unite a
condition of stress is implied in the medium which separates them.
Stress, Electro-magnetic.
The stress produced upon transparent substances in an electro-magnetic
field of force. It is shown in the modified optical properties of glass
and similar substances placed between the poles of a strong
electro-magnet.
Stress, Electrostatic.
The stress produced upon substances in an electrostatic field of force;
the exact analogue of electro-magnetic stress, and affecting transparent
substances in the same general way.
Striae, Electric.
In Geissler tubes the light produced by the electric discharge is filled
with striae, bright bands alternating with dark spaces; these may be
termed electric striae.
Striking Distance.
The distance that separates two conductors charged with electricity of
different potential, when a spark starts between them.
Striking Solution.
In silver-plating a bath composed of a weak solution of silver
cyanide-with a large proportion of free potassium cyanide. It is used
with a strong current and a large silver anode. This gives an
instantaneous deposition of metallic silver over the surface of the
article which goes to insure a perfect coating in the silver bath
proper. After a few seconds in the striking solution, the article is at
once removed to the plating bath.
Stripping.
The removal of electroplating from an object. It may be effected in
several ways. An object whose plating is to be removed is placed in a
plating bath of the solution of the metal with which it is coated. It is
connected as the anode to the positive plate of the battery or
corresponding terminal of the generator. A kathode connected to the
other terminal being placed in the bath, the coating is dissolved by
electrolytic action. Sometimes simple treatment with acid is employed.
Different stripping baths are described under the heads of the different
metals.
S. U.
Symbol or abbreviation for Siemens' Unit of Resistance. (See Resistance,
Siemens' Unit of.)
Sub-branch.
A branch or lead of wire taken from a branch lead: a term used in
electric distribution.
Sub-main.
In electric distribution a conductor connected directly to a main; a
branch.