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What is Electron

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					                    What is Electron
An electron is a subatomic particle. Carrying a negative charge, an
electron orbits an atom’s nucleus and is bound to it by
electromagnetic forces. An electron has a mass that is minuscule in
comparison with even the smallest of atoms, coming in at about one
thousandth the size of the tiniest atom. The electron is a basic unit of
nature, meaning it cannot be broken down into smaller units.
The electron plays a starring roll in many of the interactions we see
on a daily basis. For example, electrons are partially responsible for
the fact that we can stand on a flat surface and not sink right through
it. This occurs as the result of the mutual repulsion of the electrons in
both the ground and a person’s shoes. We also depend on electrons
for electrical current to power electronic devices. Even televisions rely
on electrons to function properly.

G. Johnstone Stoney, an Irish physicist, was credited with introducing
the electron concept in 1874, as well as with naming it twenty years
later. In 1897, J.J. Thompson, from Cambridge University, discovered
that the electron was a subatomic particle. It wasn’t until 1909 that the
charge of the electron was measured by Professor Robert Andrews
Millikan, an American experimental physicist. He discovered its
charge while conducting an oil-drop experiment.

Electrons are considered to be leptons. Leptons are considered
fundamental particles, meaning they cannot be broken down into
smaller units. Electrons, like other particles, are capable of acting in
waves. The electron has an antiparticle, called the positron, that has
the same mass as the electron. The positron, however, is positively
charged.
The electric charge of the electron is −1.6022 × 10−19 coulomb. Its
symbol is e−. An electron’s spin is ½ and it is a fermion, meaning it
has a half-integer spin. Inside an atom, electrons are bound to the
atom. When electrons are moving freely through space or another
medium, however, they are referred to as free electrons. Electrons
that are moving freely can be used in an electron beam.
Free electrons are responsible for the generation of electric current.
In fact, it is free electrons that generate electric current. Electrons are
used in numerous applications, including those related to industry,
science, and medicine. Electrons are also present throughout the
universe in incredibly large numbers.

				
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