Charged

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Lighterstill.jpg

Spiral zoneplate charge2.jpg

Etymology

Middle English, from Anglo-French, from charger

Definitions

b : a figure borne on a heraldic field
  • 2 a : the quantity that an apparatus is intended to receive and fitted to hold
b : the quantity of explosive used in a single discharge
c : a store or accumulation of impelling force <the deeply emotional charge of the drama>
d : a definite quantity of electricity; especially : an excess or deficiency of electrons in a body
e : thrill, kick <got a charge out of the game>
b : management, supervision <has charge of the home office>
c : the ecclesiastical jurisdiction (as a parish) committed to a clergyman
d : a person or thing committed to the care of another
  • 4 a : instruction, command
b : instruction in points of law given by a court to a jury
  • 5 a : expense, cost <gave the banquet at his own charge>
b : the price demanded for something <no admission charge>
c : a debit to an account <the purchase was a charge>
d : the record of a loan (as of a book from a library)
e British : an interest in property granted as security for a loan
  • 6 a : a formal assertion of illegality <a charge of murder>
b : a statement of complaint or hostile criticism <denied the charges of nepotism that were leveled against him>
  • 7 a (1) : a violent rush forward (as to attack) <the charge of the brigade> (2) : the signal for attack <sound the charge>
b : a usually illegal rush into an opponent in various sports (as basketball)

— in charge : having control or custody of something <he is in charge of the training program>

Description

Electric charge is a fundamental conserved property of some subatomic particles, which determines their electromagnetic interaction. Electrically charged matter is influenced by, and produces, electromagnetic fields. The interaction between a moving charge and an electromagnetic field is the source of the electromagnetic force, which is one of the four fundamental forces.

The electric charge on a body may be positive or negative. Two positively charged bodies experience a mutual repulsive force, as do two negatively charged bodies. A positively charged body and a negatively charged body experience an attractive force. The study of how charged bodies interact is classical electrodynamics, which is accurate insofar as quantum effects can be ignored.

Twentieth-century experiments demonstrated that electric charge is quantized: the charge of any system, body, or particle (except quarks) is an integer multiple of the elementary charge, e, approximately equal to 1.602×10−19 coulombs. The proton has a charge of e, and the electron has a charge of −e. The study of charged particles, and how their interactions are mediated by photons, is _electrodynamics quantum electrodynamics.