Electric Charge#
Definition: Electric Charge
Electric charge is a fundamental property of matter which allows it to interact via electromagnetism.
Electric charge is a frame-independent scalar quantity which is mathematically described by a real number. Its measurement unit in SI is the Coulomb (\(\mathrm{C}\)).
Quantization#
Definition: Charge Quantization
Charge quantization is the observation that the total electric charge of a physical object is always an integer multiple of a specific value known as the elementary charge.
Definition: Elementary Charge
The elementary charge is the following constant:
Notation
This can be largely explained by the fact that the vast majority of matter is comprised of protons, neutrons and electrons. The electric charge of a single proton and a single electron is, respectively, \(+e\) and \(-e\), while neutrons have no net electric charge. It is true that there are particles whose electric charge is a fraction of the elementary charge, but they are always bound to other such particles in a way that makes the net charge an integer multiple of \(e\).
Point Charges#
Definition: Point Charge
A point charge is a model of a physical object with electric charge which assumes that all of the object's electric charge is concentrated in a single point.
Charge Density#
TODO