As we leave a body at some point, it always falls. This is because there is a potential energy difference between where the body was and the ground.
In a common stack something similar happens. The battery as well as the plug of our house, the battery of the car or the cell phone, in short, any generator of electric power, is a device in which it was possible to establish two of its points: one that needs electrons and the other that has them left.
In a cell, at the point called negative pole there are electrons left, and at the positive pole there is a lack of electrons. If we connected these points by a conductive wire, the electrons would move and a current would appear in the wire.
Therefore, in this situation there is potential energy stored in the battery, much as it has an object situated at a height h from the ground: just letting go of it causes it to move. Similarly, when connecting a wire to the battery, a current appears in the wire.
The voltage unit in the International System is indicated by volt (V).
The most commonly used battery is 1.5V. A car battery provides 12V.
The computer works with a 5V power supply. The sockets in our house provide 110V or 220V voltage, depending on the region of the country. It is very prudent to observe the local voltage before plugging in the equipment. If we connect appliances that are programmed to operate at 110V to a 220V outlet, they can burn and even cause serious accidents.
In general, simply adjusting a key in the handsets to resolve this situation; But this key does not always exist, so be careful!
Due to the potential difference, we may get shocks. As our body is a good conductor of electricity, if we touch two points that there is potential difference, a current will flow through our body. Depending on the intensity of this current and the path it travels through the body, a shock can even lead to death.
We must be very careful with high voltage wires. The voltage on these cables reaches thousands of volts! Therefore, do not play near power poles.
And why, you may ask, aren't the birds that land on these cables electrocuted?
This is not because their paws are very close to each other and the potential difference between them is very small.
With people, the situation is different. Never touch a high voltage wire as touching a cable while touching another point on the cable or another object could result in a severe, possibly fatal, electrical shock if there is a significant potential difference between the two. points touched.