What is Voltage?
People often hear or read the word voltage. Voltage is a part of everyone’s daily life. People can read it in each electrical appliance used in their homes. Even the computer you are using to read this article right now is utilizing voltage. What is voltage? Voltage is a kind of driving force, which is electrical in nature. The word voltage is synonymous to ‘electric potential charge’ or ‘electric tension’. These terms can be used interchangeably with voltage. However, when it comes to magnetic and electrical fields, the terms are no longer acceptable as synonymous.
Specifically, voltage pertains to an electrical driving force between two points. Voltage has something to do with the electrical paths. In other words, the full amount of energy necessary to cause a minor electrical charge to move to the length of a path is the voltage between the end points of that same path. Moreover, the voltage moving along that path is divided by the enormity of the charge.
The voltage principles can be better understood using the hydraulic analogy. Using the flow of water in a pipe circuit pushed by a pump shows a similar scenario as electrical circuit flowing. This model can be called a water circuit. Two points from the water path varies in pressure and this matches up the potential difference in the case of electrical circuit. This explains the difference of pressure between two points is what enables the movement of water point A to point B.
The same principle exactly works in electrical circuits. One good example is the starter of a car. The battery of a car drives an electrical current to the starter. The potential difference makes the starter to rotate and start the car engine. If there is no potential difference from the two points (battery and starter) then no work can be done. If the battery is dead, the starter will not rotate and the car engine will not start.
From the hydraulic analogy, voltage can be also be defined as the measure of an ability to do work. It can also be concluded that the more potential difference the larger the voltage or the ability to do a work will result. Voltage is measured using a device known as voltmeter. A voltmeter is able to measure potential difference by connecting it to both points (point A and B).
Voltage can also be used to describe voltage dropped transversely to an electrical device. This voltage drop is the disparity among the two terminals of the device such as a resistor. However, the measurement from each terminal must be in respect to a ground or common reference point. The disparity from the two readings will be the voltage drop. If there is no resistance between the two points in an electrical circuit, the voltage is measured as zero.
There are other devices that are used to measure voltage aside from the voltmeter. The potentiometer is utilized to balance an unidentified voltage against a known voltage. Another instrument used in voltage is the oscilloscope, which amplifies the voltage and utilizes it to redirect an electron beam coming from a straight path. This is done to ensure that the voltage is proportional to the beam deflection.