Language and Theory
Electricity is briefly defined as the flow of electric charge, but there’s so much behind that simple statement. Where do the charges come from? How do we move them? Where do they move to? How does an electric charge cause mechanical motion or make things light up?
- The definition of electricity is the flow of charge. Usually our charges will be carried by free-flowing electrons.
- Negatively-charged electrons are loosely held to atoms of conductive materials. With a little push we can free electrons from atoms and get them to flow in a generally uniform direction.
- A closed circuit of conductive material provides a path for electrons to continuously flow.
- The charges are propelled by an electric field. We need a source of electric potential (voltage), which pushes electrons from a point of low potential energy to higher potential energy.
Current Electricity and Circuits
Current electricity is the form of electricity which makes all of our electronic gizmos possible. This form of electricity exists when charges are able to constantly flow.
In order to flow, current electricity requires a circuit: a closed, never-ending loop of conductive material. A circuit could be as simple as a conductive wire connected end-to-end, but useful circuits usually contain a mix of wire and other components which control the flow of electricity.
The only rule when it comes to making circuits is they can’t have any insulating gaps in them.
If you have a wire full of copper atoms and want to induce a flow of electrons through it, all free electrons need somewhere to flow in the same general direction. Copper is a great conductor, perfect for making charges flow. If a circuit of copper wire is broken, the charges can’t flow through the air, which will also prevent any of the charges toward the middle from going anywhere.