School

# What is Voltage: Concept, Types of Voltage and How to measure it

## We explain what the voltage is and the types that exist. Also, what is Ohm's Law and how is this magnitude measured.

### What is the voltage?

We define voltage as the amount of potential difference between two points in a circuit. One point has more charge than another. The difference in charge between the two points is called the voltage.

It is measured in volts, which is technically the work per unit of electric charge that an electric field exerts on a particle in order to move it between two determined points. (don’t panic if you don’t understand, everything will be explained). The “volt” unit was named after an Italian physicist Alessandro Volta who invented what is considered to be the first chemical battery. According to the International System (SI), voltage is represented in the equations and the schematics by the letter “V”

When two points that have an electrical potential difference are joined with a conductive material, a flow of electrons will occur, which is known as an electric current, which will carry part of the charge from the point of high potential to low potential.

When same amount of voltage is present on both points of the electric conductor then current or charge does not flow from one point to the other, unless a certain potential difference is maintained by a generator or an external source of some kind.

Thus, the voltage of a single point is always 0V. As we have learned that voltage is the potential difference and

When describing voltage a common analogy is a pond of water. In this analogy, the load is represented by the amount  of water, the voltage is represented by the pressure  of the water, and the current is represented by the flow  of water. So for this analogy remember:

• Pressure = Voltage
• Flow = Current

Consider a pond of water at a certain height above the ground. At the bottom of this tank is a hose. The pressure at the end of the hose can represent the voltage. The water in the pond represents the charge. The more water there is in the pond, the higher the load, and the greater the pressure measured at the end of the hose.

We can think of this pond as a battery, a place where we can store a certain amount of energy and then release it. If we empty our pond a certain amount, the pressure created at the end of the hose drops. We can think of this as the decreasing voltage, like when a flashlight goes dark when the batteries are discharged. There is also a decrease in the amount of water that will flow through the hose. Less pressure means there is less water flowing, which brings us less flow or less current.

In conclusion, a circuit equipped with high voltage will have a greater capacity for work  (the water moves with greater force, in the previous example) and therefore it will be more powerful or even more dangerous.

It can serve you: Power supply

### Voltage types

There are the following types of voltage:

• Induced voltage . it is defined as the amount of voltage generated by the electric field, magnetic field or an electric current. it can be a man made or a natural. Example: 1. Voltage generated by a generator due to the moving magnetic field. 2. Voltage generated in the secondary coil of a transformer due to the magnetic feild. he induced voltage of a closed-circuit is described as the rate of change of magnetic flux through that closed circuit.
• Alternate voltage . It is a voltage which changes it’s magnitude with respect to time. with positive and negative values ​​on a Cartesian axis, since it is considered a sine wave. It is the most common voltage in electrical outlets because it is the easiest to generate and transport. As its name implies, it is a voltage with alternate values, not constant in time and its frequency will depend on the country or the specific region. Example: A 230 V 50Hz supply means, it’s voltage magnitude changes 50 times in one second.
• Direct current voltage . It is the voltage which does not change its magnitude with respect to time. It is usual in motors and  batteries. The generation of the DC voltage is simple and easy. The voltage induced when a coil is rotated in the magnetic field where the coil has the split ring and commutator which converted the alternating voltage into direct voltage. It does not has the magnitude not it is 0Hz.
• Continuous voltage . Also called direct current voltage  (VCC), it is the purest current available, present in chips,  microprocessors,  and other devices that require continuous and constant voltages. It is usually obtained after treatment with electrolytic capacitors.

### How is the voltage measured?

To measure the voltage a voltmeter is used , which is installed parallel to the power source to measure and quantify the electrical potential. Other devices used are the tester (or multimeter) and the potentiometer.

In any way, the voltage is calculated taking into account the total energy necessary to mobilize a small electric charge from the beginning to the end of the circuit, divided by the magnitude of said charge.

### CircuitSchools Staff

We at CircuitSchools publish on basics of electronics and electric components and everything related to evolution of electrical technology with complete analysis of development boards and modules along with latest projects with innovative ideas.