An electric arc provides a demonstration of electric current.
Electricity is the set of physical phenomena associated with the presence and flow of electric charge. Electricity gives a wide variety of well-known effects, such as lightning, staticelectricity, electromagnetic induction and electrical current. In addition, electricity permits the creation and reception of electromagnetic radiation such as radio waves.
In electricity, charges produce electromagnetic fields which act on other charges. Electricity occurs due to several types of physics:
electric charge: a property of some subatomic particles, which determines their electromagnetic interactions.
electric field: an simple type of electromagnetic field produced by an electric charge even when it is not moving (i.e., there is no electric current).
electric potential: the capacity of an electric field to do work on an electric charge, typically measured in volts.
electric current: a movement or flow of electrically charged particles, typically measured in amperes.
- electromagnets: Moving charges produce a magnetic field. Electrical currents generate magnetic fields, and changing magnetic fields generate electrical currents.
In electrical engineering, electricity is used for:
electric power where electric current is used to energise equipment;
- electronics which deals with electrical circuits that involve active electrical components such as integrated circuits, and associated passive interconnection technologies.
Electrical phenomena have been studied on Terra since antiquity, though progress in theoretical understanding remained slow until the seventeenth and eighteenth centuriesCE. Even then, it would not be until the late nineteenth century that engineers were able to put it to industrial and residential use. The rapid expansion in electrical technology at this time transformed industry and society. Electricity's extraordinary versatility means it can be put to an almost limitless set of applications which include transport, heating and lighting.
Electrical power is now the backbone of modern Union industry.