Electrical potential between two points is called voltage. Potential difference between two points moves electrons in the connected circuit and, create an electrical current. This current allows operating the electrical devices such as lighting devices.
The unit of voltage is volt and represented as letter V. For example: 9 V, 12 V, 24 V, 110 V, 220 V.
Voltage indicates that how much potential energy needed in order to move the electrons from one point to another. If the voltage is high the ability to move the electrons in the circuit will raise up.
Assume that there is a container filled with water and there is a tap under this container. If the water level is high in the container, water flows at a high speed due to high pressure from the tap. Similar to this situation, electrons are more efficient under high voltage.
Voltage is divided into two, alternating current (AC) and direct current (DC). Direct current always has the same polarity. However, in alternating current, the polarity changes continuously at a certain frequency. For example, the polarity of network electricity in Turkey changes 50 times per second.
There is 220 V AC voltage in sockets in our homes. There is a 1.5 V voltage in the AA and AAA batteries used in many electronic devices at home. Cars generally have 12 V DC voltage.
Turkey and many European countries use 220-230 V mains voltage. However, some countries have 110-120 V mains voltage.
The devices connected to the sockets in homes are designed to work with 220 V voltage. Remote controls with batteries operated with 1,5 V or 3 V DC. Electric equipment on the car works with 12 V DC voltage.
Some electronic devices are designed to operate within a wide range of voltage ranges, such as 100-240 V. These devices can be used in different countries without requiring any converter.
When two power supply with the same voltage in the circuit is connected to each other as serial, that makes the voltage double. When it is connected as parallel the voltage remains constant, but the current capacity increases. For example, if you connected two 12 V battery as serial, you will have 24 V. When you connect as parallel, the voltage will remain constant as 12 V.
In order to measure the voltage, the devices such as; voltmeter, multimeter, and oscilloscope are used.