Units of Electricity

Introduction

The movement of electrons in an object provides the energy to do work. This energy is called electrical energy. The ratio of electrical energy absorbed is called an electrical power. There are many types of energy like electrical energy, mechanical energy, thermal energy, light energy, and wind energy. In our daily life, we get electrical energy from the battery. We are well aware of the movement of air and the flow of water.

Similarly, the flow of an electric charge in a conductor is called current. Energy is needed to work. That is, the ability to do work is defined as energy. Hence work and energy have the same dimension. Batteries and other power sources act like pumps, they push charges to flow through a wire or conductor. This pushing action of power sources is done by their electromotive force.

What is Electricity?

Electricity is a natural phenomenon caused by the movement of electric charge. The flow of charged particles is what we call electricity. In nature, electricity is caused by the flow of particles or current flowing from the ground to the earth. Although electricity was initially considered a separate phenomenon unrelated to the magnetic phenomenon, after the formulation of Maxwell’s equations, it became clear that electricity and magnetism are components of a unified electromagnetic phenomenon.

When current flows through a coil, an electromagnetic field is created around the coil. Many phenomena are related to electricity like lightning, static electricity, electric heating, and electric discharge. Electricity is the lifeblood of many modern technologies.

SI and Other Units of Electricity

Ampere

Any cross-sectional area of the conductor obtains one coulomb of charge in one second, and the current in the conductor is one ampere.

Volt

Both electromotive force and potential difference have the same SI unit ‘volt’. One volt is defined as the force acting on the charge when an electric battery moves a charge by one joule of work done.

$$\mathrm{V=\frac{W}{q}}$$

Thus a certain amount of electrical energy in the battery or electrical energy source is converted into light energy, mechanical energy, or thermal energy. The potential difference is denoted as V . The potential difference across the device determines the amount of electrical energy converted to other forms by each coulomb of charge passing through a light bulb (or other electrical devices).

Watt

Watt is the SI unit of electric power. The rate of work done is called Power. One watt is the power used by an electrical appliance operating at one volt of potential difference causing one ampere of current. So,

$$\mathrm{1\:Watt=1\:Volt\times 1\:Ampere}$$

An older unit of power called horsepower (hp) is still in commercial use for motors, engines, and some automatic vehicles. To convert horsepower (hp) to watts (W) use the following formulae.

$$\mathrm{1\:Horse\:power = 745.699872\: Watt}$$

Watt-hour

A unit of electrical energy is a watt-hour. A watt-hour represents 1-watt power used for 1 hour. Commercially we measure electrical energy in kilowatt-hours. It is commonly referred to as a unit. Measuring electrical energy in the small unit of watt second requires dealing with large numerical values. Therefore, electrical energy is measured in units of a kilowatt-hour (kwh). Kwh is the unit of energy; Is not a unit of Power. Electricity tariffs are prepared in units of kilowatt-hour for electrical energy consumption.

Static Electricity

Static electricity is caused by a balanced variation of charge on the surface or interior of a conductor. It is called static electricity because it remains in one place until it is moved by current or discharge, in contrast to the current, which transfers energy through conductors.

When two surfaces in contact separate, a charge will develop if either surface is an obstacle to current flow. When this charge moves towards the ground and is caused by people, the effect can be heard mechanically, felt as vibration, or seen as a small spark. This familiar phenomenon, called static discharge, occurs when the charge reaches the neutral ground.

Dynamic Electricity

The motion of electric charge in a conductor produces dynamic electricity. An electric circuit is the best example of dynamic electricity. The flow of electric charge occurs in electric source devices such as batteries and generators.

The conductive material has a high flow of electric charge. So they conduct electricity more. For example, metals always have one or two free electrons in the outermost orbit. So they can be attracted by the other atoms. Thus the electric charge flows in a metal.

Current

The flow of electric charge is called current. For electrical devices to operate, current must flow through the conductors. The matter is inclusive of atoms and molecules. The current is denoted as ‘I’. If a charge of current ‘q’ passes through a given cross-sectional area of the wire in time ‘t’ the magnitude of the current,

$$\mathrm{I=\frac{q}{t}}$$

When a charged material is given a conducting path, electrons flow from a higher voltage to a lower voltage along the path. Usually, the voltage difference is provided by a battery. As the electron move, a charge is created. That is, electric charge is created by moving electrons.

Applications

• Electronic circuits consist of active electrical elements and processing elements such as resistors, integrated circuits, dipoles, vacuum tubes, and the connection technologies that connect them.

• The rapid development in electronic technology has greatly transformed society and industries. As it becomes more common, everything from transportation to heating to lightning to telecommunications.

• Electricity is the lifeblood of today’s society used for a variety of applications.

Conclusion

The matter is inclusive of atoms and molecules. Every atom consists of particles like protons, neutrons, and electrons. The movement of these charged particles in an object causes an energy. This energy is called electrical energy. The rate of electrical energy absorbed is called an electrical power. The rapid development in electronic technology has greatly transformed society and industries. For electrical devices to operate, current must flow through the conductors.

FAQs

Q1. What is Alternating Current?

Ans. If a battery is producing current whose direction is alternating with time, then it is called alternating current. It varies in a sinusoidal manner with time.

Q2. Why copper wires are used in home electrical circuits?

Ans. Copper conductors have very low resistance, because of this property, copper wires are used in home electrical circuits.

Q3. What is an Ammeter?

Ans. An electric current in a circuit is measured by an ammeter. Ampere is the measurement unit of current. As a result of this, it is named Ammeter.

Q4. What is Shunt?

Ans. The shunt is a part of an electric circuit which provide an alternate path to the flow of current to measure it. A shunt is used in an ammeter which is based on the principle that the resistance value must be very less and there should be no change in current while measuring it.

Q5. Explain about batteries

Ans. Batteries store the electrical energy which is converted from the process of chemical reactions in it. A battery is formed in which two different metal plates are fixed as electrodes.