Basic Properties of Electrical Charge

Introduction

Basis properties of electric charge characterise the matter made of particles when put in either an electric field or a magnetic field. The charges are represented by two sign conventions i.e., Positive and negative. It is produced when two bodies are rubbed with each other.

Here the charges are transferred from one body to another body. This phenomenon is also known as static electricity because there is no flow of charge. In our day-to-day life, we also produce charges when walking on the carpet, there is friction between shoes and the carpet. Electric charge is a simple form of electron and is the cause of the production of the electric field. Since the electric charge can flow from one end to another end in any circuit and conductor, this is known as current.

Electric Charge Definition

It is a physical effect of the substance. It experiences power when it is put in an electric or magnetic field. It is a Scalar quantity that only has magnitude.

Electric charge is basically of two types

• Positive charge

• Negative charge

The body which donates the charge is known as positively charged. Similarly, the body which receives the charge is negatively charged. Similar charges force back each other and dissimilar charges move towards each other. Everybody carries some charges. The bodies which do not have any charges mean they are neutral. The symbol for electric charge is q.

If we define the charge mathematically, this is equal to the integer multiple of the charge of one electron 1.6×10^-19 C

$$\mathrm{Q=ne}$$

$$\mathrm{Q=total\:charge}$$

$$\mathrm{e= charge\:on\:electron}$$

$$\mathrm{n= number\:of\:electron}$$

Basic properties of Electric Charge

Conservation of Electric charge

The conservation of electric charge states that a charge can neither be created nor demolished; it can only be conveyed from one body to another body by a process like induction and conduction. This is somewhat similar to the conservation of mass law and is also similar to the first law of thermodynamics.

Example: let's assume that a system has a total charge of 15 coulombs. Now we can redistribute this charge to 2C,4C,4C,and 5C.

Similarly, we can redistribute it to any other combinations as well.

Additive Nature of Electric Charges

According to the rule if there are multiple charges present in the system. We can directly add them. Thus, charge can be considered as a scalar quantity. Note that the sign of the charge (positive or negative) has to be taken into consideration while applying this rule.

Let's take an example of a system having n number of charges $\mathrm{q_1, q_2,q_3.................q_n}.$

Thus, the total charge of the system Q is equal to

$$\mathrm{Q=q_1+q_2+q_3..................................q_n}$$

Quantization of Electric Charge

This principle states that net charge within a body is an integral multiple of the basic unit of charge e which is equal to $\mathrm{1.6×10^{-19}C}$. This essentially means that the charge is a fixed quantity. This principle can be written as

$$\mathrm{Q=ne}$$

Here, Q is a charge, e is the charge of an electron or proton and n is the number of electrons

Transferrable

One other property of charges is that they are transferred from one body to another body. If one charged body is taken too close to another unchanged body then charges (electrons) move from charged body to the uncharged body and this unchanged body becomes charged after transferring the electrons. The nature of the charged body decides the flow of electrons from where the electron moves.

Attraction and Repulsion

Like charges repel to each other. These are the very important characteristics of charges that they repel when they are of the same nature of charges. That means the positive charge repels the positive charge and the negative charge is repelled by the negative charge.

Unlike charges are attracted to each other. It means the negative charge attracts the positive charge and the positive charge is also attracted by the negative charge only.

Charge has Mass

A charge is linked with mass. It means charge cannot exist without mass

The property of Invariant Charge

Charge of the body is not dependent on the speed of the body in the system and the frame of reference.

Charges can Radiate

Stationary charge produces an electric field and moving charge produces a magnetic field. When charged particles are accelerated then it produces both electric and magnetic fields.

The Unit of Electric charge

The SI unit of the electric charge is coulomb which is denoted by ,C.

The CGS unit of the electric charge is an electro-stat unit

$$\mathrm{1\:coulomb=3×10^{9 } esu}$$

Electric Charge and Field

Whenever a charge is placed in an electric field it experiences a force on it.

$$\mathrm{F=QE}$$

Here, E is electric field intensity, Q is the charge, and F is the force on the charge.If the charge is positive then the force is acting on it in a direction in the electric field and if the charge is negative then the direction of the force on the charge is opposite to the electric field. The electric field due to a point charge is equivalent to the ratio of force to the charge.

$$\mathrm{E=\frac{F}{Q}}$$

S.I unit - newton couloumb^-1

Conclusion

This article helps us to understand electric charges in detail. Now we are aware of its unit, its nature, its all-important properties, and what is the relationship between electric charges and electric field. Electric charges are always conserved, invariant, Quantized and transferrable. They exert attractive and repulsive force on each other depending upon their nature. Charges have always mass and they radiate when they accelerates.

FAQs

Q1. Write down the methods of charging?

Ans. There are mainly three methods of charging a body.

• By conduction

• By friction

• By induction

Q2. Write down the dimensional formula of the electric charge?

Ans. By formula of the current

$$\mathrm{Q=I×t}$$

So, the dimensional formula of charge is $\mathrm{[M^0 L^0 T^1 A^1 ]}$.

Q3. Give an example that has a positive, negative, and neutral charge

Ans. In an atom, a nucleus has a positive charge, the electron has a negative charge and the neutron does have any charge. It is neutral. Electrons and protons have charges of the same magnitude but nature is different.

Q4. Write down the practical unit of charges?

Ans. One practical unit is ampere-hour.

$$\mathrm{1\:ampere-hour=3600C\:and\: 96500F}$$

Q5. Write the definition of electric field

Ans. The electric field is the region of space all around the charge where a unit positive test charge experiences a force. It is defined by force per unit charge.