How does current electricity work?

Answer 1

First you need to understand charge, voltage and current.

Atoms are made of electrons, neutrons and protons. Electrons have a kind of charge called negative charge and protons have a positive charge. Neutrons have both negative and positive charges, so they cancel out and are not very important to electricity. Like charges repel each other, while opposite charges attract each other. This is what causes electricity.

Sometimes atoms will have more electrons than protons or vice versa. When there are many atoms of something have too few or too many electrons then it gains a net charge depending on if there are more electrons or more protons. If there are more electrons then it has a negative charge, if it has more protons it has a positive charge.

Voltage is the difference between two charges. On a 9-volt battery, the difference between charge of the positive terminal and the negative terminal will be nine times as much as the difference of charge on the terminals of a 1-volt battery.

Now since opposite charges attract, the electrons in the negative terminal want to move to the positive terminal (protons don't move because they are in the center of an atom). The only thing stopping the electrons from jumping to the positive terminal is air because it has a lot of resistance.

Resistance is how hard it is for electrons to move through a material. Copper wire has a very low resistance, so when you connect the two terminals together with wire, electrons start moving across the wire from the negative terminal to the positive terminal. Electrons move slowly across the wire, but they start a chain reaction in the atoms that make the wire so that now almost all the atoms want to give some of their electrons to the positive terminal. This reaction moves very fast, almost at the speed of light, and that's things power up almost instantly once they are connected to a power source even though the electrons themselves move slowly. The movement of these electrons is called current, and that's what powers electric devices.

Answer 2

Electric current is the rate of charge flow past a given point in an electric circuit, measured in Coulombs/second which is named Amperes. In most DC electric circuits, it can be assumed that the resistance to current flow is a constant so that the current in the circuit is related to voltage and resistance by Ohm's law. The standard abbreviations for the units are 1 A = 1C/s.