Cables are generally considered to be wires that are ma […]
Cables are generally considered to be wires that are made of one or more mutually insulated conductors with insulation and protective layers, which transmit electricity or information from one place to another. In a broad sense, it refers to a device that uses metal as a medium to transmit electrical signals.
By definition, cables are used to conduct electricity. Generally made of the following metals:
Copper's electrical conductivity is second only to silver, and its thermal conductivity is second only to gold and silver; it is corrosion resistant, non-magnetic, good plasticity, easy to solder, and has a wide range of uses. Copper alloys mainly improve the wear resistance, corrosion resistance and mechanical and physical properties of copper.
Silver, the metal has the highest conductivity and thermal conductivity, has good corrosion resistance and oxidation resistance, and is easy to weld; it is mainly used for plating and cladding;
Gold and nickel are used as high temperature resistant wires.
Iron (steel) is often used as a reinforcing material for composite conductors, such as steel core aluminum wire, copper clad steel, and aluminum clad steel wire.
Zinc is used as coating for steel wire/steel strip/iron conductor to prevent corrosion.
Tin is used as the coating of steel wire/copper wire to prevent corrosion and facilitate the welding of copper wire.
Optical fiber is an abbreviation of optical fiber, which is a light transmission tool that uses the principle of total reflection of light in a fiber made of glass or plastic. The former presidents of the Chinese University of Hong Kong Gao Kun and George A. Hockham first proposed the idea that optical fiber can be used for communication transmission. For this reason, Gao Kun won the 2009 Nobel Prize in Physics.
The transmitting device at one end of the optical fiber uses a light emitting diode (LED) or a laser beam to transmit light pulses to the optical fiber, and the receiving device at the other end of the optical fiber uses a photosensitive element to detect the pulses.
In daily life, since the transmission loss of light in optical fibers is much lower than that of electricity in wires, optical fibers are used for long-distance information transmission.