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[1] 6th century BC – Greek philosopher Thales of Miletus observes that rubbing fur on various substances, such as amber, would cause an attraction between the two, which is now known to be caused by static electricity. He noted that rubbing the amber buttons could attract light objects such as hair and that if the amber was rubbed ...
The earliest Chinese literature reference to magnetism lies in a 4th-century BC book called The Book of the Devil Valley Master: "When the people of Cheng go out to collect jade, they carry a south-pointer with them so as not to lose their way." [9]: 110 [10] Electric catfish are found in tropical Africa and the Nile River.
History [ edit ] After the discovery in the 1800s of Faraday's law of induction , which showed that an electromotive force could be generated by a changing magnetic field , several scientists speculated that this effect could be used to accelerate charged particles to high energies. [ 2 ]
The Italian Guglielmo Marconi transmits wireless telegraph messages by electromagnetic waves over a distance of five kilometers. 1898 The Danish physicist Valdemar Poulsen creates the world's first magnetic recording and reproduction, using a 1 mm thick steel wire as a magnetizable carrier.
The electromagnetic force is one of the four fundamental forces of nature. It is the dominant force in the interactions of atoms and molecules. Electromagnetism can be thought of as a combination of electrostatics and magnetism, which are distinct but closely intertwined phenomena. Electromagnetic forces occur between any two charged particles.
A Bitter electromagnet or Bitter solenoid is a type of electromagnet invented in 1933 by American physicist Francis Bitter used in scientific research to create extremely strong magnetic fields. Bitter electromagnets have been used to achieve the strongest continuous manmade magnetic fields on earth―up to 45 teslas , as of 2011 [update] .
35.4 T – the current (2009) world record for a superconducting electromagnet in a background magnetic field [19] 45 T – the current (2015) world record for continuous field magnets [19] 97.4 T – strongest magnetic field produced by a "non-destructive" magnet [20] 100 T – approximate magnetic field strength of a typical white dwarf star
The theory of special relativity plays an important role in the modern theory of classical electromagnetism.It gives formulas for how electromagnetic objects, in particular the electric and magnetic fields, are altered under a Lorentz transformation from one inertial frame of reference to another.