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The discovery of cathode rays led to the discovery of the electron.

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The electron is a fundamental subatomic particle.
It was discovered by an Englishman called J.J. Thomson in 1897.
It received its name from an Irishman, George Stoney.
Its negative charge was identified by a Frenchman called Perrin in 1895 and the size of its charge was measured by an American, called Milikan in 1909.
Electrons spend most of their time orbitting the nucleus of atoms.

A typical atom
is like a
mini-solar system.
In the diagram, electrons orbit the nucleus.

Electrons are very small, far smaller than an atom.The mass of an electron is less than one thousandth of that of the smallest atom. If electrons leave an atom and move through a material under the influence of a voltage, this is known as electric current. Modern life is heavily dependent on electricity. Since the motion of electrons is at the heart of electricity, we are very dependent on the electron and perhaps we should get better acquainted.

  Electron in orbit around a nucleus

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