Electricity and Magnetism Main Page
Electricity and magnetism are very closely related so they are often studied together as one topic.
Electricity and magnetism play a vital role in modern society. Without them modern life would be impossible and we would return to the stone age. There could be no light except from fire, or perhaps chemicals. There would be no refrigeration, no air conditioning, and no heating systems other than the fireplace. There would be no radio or television. No movies or stored music. No flashlights and no automobiles, or airplanes. There would be no calculators or computers and no video games.
Without them we would still be using horse drawn buggies, and probably bicycles. We would be using lamp oil, if we could drill deep enough to get oil.
Imagine getting rid of everything you have that uses any form of electricity, and anything that required the use of electricity to manufacture it. We would still be able to operate the old printing presses by hand. We could walk instead of driving our automobile.
We owe a lot of our modern way of life to the likes of Benjamin Franklin, William Gilbert, Charles Augustin de Coulomb, Karl Friedrich Gauss, Hans Oersted, Michael Faraday, James Clerk Maxwell, Heinrich Hertz, and Guglielmo Marconi.
Let us start our study of electricity and magnetism by looking at the electric charge.
An electric charge can be produced by rubbing two objects together. This can be as simple as walking over a wool carpet which will cause an electric charge to build up on the body. When you touch a doorknob after walking on a wool carpet you may feel an electric shock as the electric charge travels from you to the doorknob. Electrification is the process which produces this charge on an object. The stationary electricity in the form of electric charge is called static electricity.
There are two types of electric charge. Positive and negative. This was discovered by Benjamin Franklin. He is said to have named them as such.
Note: Like charges repel each other and unlike charges attract each other.
Note: Electric charge is always conserved.
Note: Negative charge is transferred from one object to another.
Note: Positive charge is caused by a lack of electrons.
The electroscope is a device that is used to detect electric charge. There are two main kinds of electroscopes, the leaf electroscope, and the vane electroscope.