Voltage is the electrical potential difference caused by the accumulation of electric charges on a point, or a material.
If we remove electrons from a material, its total electric charge will be positive.
Remember that we are removing electrons, which are negatively charged, from a neutral atom (which has no charge). This causes the atom is no longer neutral but have a positive charge.
We can see that there are 6 protons in the atom (positive charge) and 4 electrons (negative charge). In conclusion, the total charge is positive.
If we increase the amount of electrons in a material, its total electric charge will be negative.
We can see that there are 6 protons in the atom (positive charge) and 8 electrons (negative charge). In conclusion, the total electric charge is negative.
If we have two materials with different levels of electric charges, then we say that there is a potential difference between them.
To change the electric charge of a material it is necessary to apply energy to the atom. There are several methods for doing this:
- Friction
- Pressure
- Heat
- By magnetism
- By chemical action
When two points having a potential difference are linked through a conductor, it produces an electrical current flow. The electric current flows from the point with greatest potential, to the point with lower potential. This is the case of a voltage source.
The potential difference (voltge) is measured in volts (V).
