This article explains electron theory and atoms. Find out why like forces repel and unlike forces attract each other.
Atoms and electrons
Electron theory states all matter is comprised of molecules, which in turn are comprised of atoms, which are again comprised of protons, neutrons and electrons. A molecule is the smallest part of matter which can exist by itself and contains one or more atoms.
If you turn on a light switch for example you will see the light bulb (globe) glow and emit light into the room. So what caused this to happen? How does energy travel through copper wires to light the bulb? How does energy travel through space? What makes a motor turn, a radio play?
To understand these processes requires an understanding of the basic principles. For the light to glow requires energy to find a path through the light switch, through the copper wire and this movement is called electron flow. It is also called current flow in electronics. This is the first important principle to understand.
The word matter includes almost everything. It includes copper, wood, water, air….virtually everything. If we were able to take a piece of matter such as a drop of water, divided it by two and kept dividing by two until it couldn’t be divided any further whileit was still water we would eventually have a molecule of water.
A molecule, the smallest particle which can exist, of water comprises two atoms of Hydrogen and one atom of Oxygen – H2O.
An atom is also divisible – into protons and electrons. Both are electrical particles and neither is divisible. Electrons are the smallest and lightest and are said to be negatively charged. Protons on the other hand are about 1800 times the mass of electrons and are positively charged. Each are thought to have lines of forces (electric fields) surrounding them. In theory, negative lines of force will not join other negative lines of force. In fact they tend to repel each other. Similarly positive lines of force act in the same way.
The fact that electrons repel electrons and protons repel protons, but electrons and protons attract one another follows the basic law of physics:
Like forces repel and unlike forces attract.
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