Search results
Results From The WOW.Com Content Network
The rich copper deposits of Cornwall seem to have been largely untouched, in spite of extensive tin mining in the region, for reasons likely social and political rather than technological. [111] In North America, native copper is known to have been extracted from sites on Isle Royale with primitive stone tools between 800 and 1600 AD. [112]
Magnetochemistry is concerned with the magnetic properties of chemical compounds and elements. Magnetic properties arise from the spin and orbital angular momentum of the electrons contained in a compound. Compounds are diamagnetic when they contain no unpaired electrons. Molecular compounds that contain one or more unpaired electrons are ...
Copper's higher tensile strength (200–250 N/mm 2 annealed) compared to aluminium (100 N/mm 2 for typical conductor alloys [16]) is another reason why copper is used extensively in the building industry. Copper's high strength resists stretching, neck-down, creep, nicks and breaks, and thereby also prevents failures and service interruptions. [17]
Magnetism is the class of physical attributes that occur through a magnetic field, which allows objects to attract or repel each other.Because both electric currents and magnetic moments of elementary particles give rise to a magnetic field, magnetism is one of two aspects of electromagnetism.
Bronze is usually nonmagnetic, but certain alloys containing iron or nickel may have magnetic properties. Bronze typically oxidizes only superficially; once a copper oxide (eventually becoming copper carbonate) layer is formed, the underlying metal is protected from further corrosion. This can be seen on statues from the Hellenistic period.
These classifications indicate chemical composition and magnetic properties. (The classification numbers themselves do not directly relate to the magnet's properties; for instance, a higher number does not necessarily indicate a stronger magnet.) [ 8 ]
The chemical elements can be broadly divided into metals, metalloids, and nonmetals according to their shared physical and chemical properties.All elemental metals have a shiny appearance (at least when freshly polished); are good conductors of heat and electricity; form alloys with other metallic elements; and have at least one basic oxide.
Inductor made with magnet wire wound around a toroidal core. Magnet wire [1] or enameled wire is a copper or aluminium wire coated with a very thin layer of insulation.It is used in the construction of transformers, inductors, motors, generators, speakers, headphones, hard disk head actuators, electromagnets, electric guitar pickups, and other applications that require tight coils of insulated ...