Direct current (DC)
This is the type of electricity that is created from batteries.
In a battery chemical energy is converted into electrical energy.
Batteries are filled with a sustance named electrolyte fluid and two different types of metal.
The metals have different electrical properties, and one is connected to the negative and the other to the positive end of the battery.
The metal connected to the negative terminal gains is negatively charged. The metal attached to the positive terminal becomes positively charged.
While the battery remains unconnected the electrons on the negative terminal cannot reach the positive terminal.
If the two terminals of the battery are connected together via a conductive material, electrons are then able to pass from the negative terminal to the positive terminal creating an electric circuit.
As the electrons move through the wire they loose energy and this energy turns into heat. Since the energy that the electrons have comes from chemical energy in the electrolyte eventually the battery will become flat.
Most DC circuits are relatively low in voltage; for example, your car's battery is approximately 12 V, and that's about as high a DC voltage as most people ever use.
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