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Precis About Electric Energy and Power

Electrical energy and Electrical power are two of the most commonly used phrases in electrical and electronic systems. This article will discuss the electrical energy and power formula, rate of charge flow and electrical energy and power units.

We use electrical energy to power various electrical devices in our daily lives. The quantity of energy transmitted in an electric circuit for a certain period is known as electric power. Energy is defined as the ability to carry out any task. Work is done when a force moves an object from one point to another. Every day, we use energy, which comes in various forms. Electrical energy is another type of energy that a charged particle can store in the electric field. Areas surrounding a charged particle are known as electric fields. Charged particles, in other words, form electric fields that exert force on other charged particles inside the field.

Definition of  Electric energy 

Electrical energy is defined as the work done by the source of electricity to maintain the rate of flow of charge in an electrical circuit. 

The movement of an electric charge produces electrical energy. Kinetic Energy is the movement of charges from one location to another. The capacity to carry more electrical energy grows as the speed of the electric charge transfer increases. 

According to the conversion law, ‘Energy cannot be converted nor destroyed, but it can be altered from one form to another. Electrical energy is transferred from one form to another in the same way. 

For example, when you turn on a light bulb, electrical energy is converted into light and heat. Electrical energy can be utilised to power and run a wide range of electrical devices.

Electrical energy can be denoted as ‘W’ or ‘E’.

Functioning of Electrical Energy

For electricity to function, electrons and protons are required. Electrons in the copper wire are free to move; hence it is the basic principle. There is a negative charge on each electron. It moves due to attraction forces between electrons and positive electrical charges (such as protons and positively-charged ions) and repulsive forces between electrons and negative charges (such as other electrons and negatively-charged ions).

In other words, the electric field that surrounds a charged particle (in this case, an electron) exerts an attractive or repulsive force on other charged particles, causing them to move and hence carry out work. Electrons, protons, atomic nuclei, positively charged ions and anions (negatively charged ions) are charged particles that can produce electrical energy.

Electrical Energy Formula

Let us consider a basic circuit with a power source (battery), a resistance and a conductor to complete the current flow.

Assume ‘V’ is the potential difference existing across a circuit, ‘I’ is the current flowing through it, ‘Q’ is the charge and ’R’ is the resistance.

Then work done by the electrical charge will be,

W = V*Q

We know that,

I = Q/t

It can be written as, 

Q = I t

When current ‘I’ flow through a conductor for ‘t’ seconds, the total work done by the charge ‘Q’ is

W = V*I*t 

Therefore, the Electrical Energy formula can be given as follows,

E = V*I*t joules

Basic Units of Electrical Energy

SI units of Electrical Energy are given in joules or watts-sec. Also, electrical energy is measured in the other units like ergs and calories.

The electrical energy (i.e. electricity) is mostly measured in the Electron-watt, Kilowatt-hour (kWh) and Megawatt-hour (MWh).

Since V = IR

E= I2R*t Or I = V/R

Thus, E = V2t/R

Definition of  Electrical Power

Electrical power is the rate at which work on an electrical circuit is completed. Working generates energy, as we already discussed. As a result, electric power can be defined as the rate of electrical energy consumed in a circuit per unit of time.

Electrical power can be denoted as ‘P’.

Now we know that work done is given as,

W = VQ

Electrical power is defined as the amount of electrical work carried out per unit of time. As a result, we can write in derivative form as,

Power = dQ/dt

As, current (I) = dQ/dT

The electrical power formula is given as,

Power (P) = V*I  watts

Basic units of Electrical Power

SI units of electrical power are given as Watt (W) or Joule/Sec (J/s).

Sometimes, Electrical power is measured in ergs per second.

Volts are used to measure voltage, whereas amperes measure current.

Watt is the unit of power as a result. However, because watt represents a small number, greater ratings are expressed in kilowatt-hours.

Therefore, P = V*I

And V = I*R

Thus P = I2R Or I = V/R

Therefore, P = V2t/R

Conclusion

As a result of this explanation, we can conclude that the current flowing through an electrical circuit is related to electrical energy and power. Electrical energy manifests itself as heat and power is measured in units of consumption time. The units of electrical energy are given in joules and electrical energy is given in watts. E stands for electrical energy, while P stands for electrical power. The value of energy is calculated as the product of power and time. On the other hand, power is the product of the potential difference between two conductor ends and the current running through them.

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What are Electric energy and Electrical Power?

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What are the units of Electric energy and power?

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Mention the differences between electrical energy and electrical power?

Ans – Electrical energy can be easily changed into another form o...Read full