Basic Properties of Electric Charge
Electric charge is a fundamental physical property of matter responsible for electrical forces and interactions. There are two types of electric charges: positive charge and negative charge. The important properties of electric charge include additivity of charge, conservation of charge and quantization of charge.
The phenomena of two objects sticking together can be explained by the notion that objects when rubbed can gain a net electric charge.
There are two types of charge, labeled positive ( + ) and negative ( - ), with the following basic property:
- Like charges of the same sign repel each other.
- Unlike charges of the opposite sign attract each other.
Kinds of charges
Negative charge and Positive charge
1. Negative charge
Electrons are negatively charged particles and protons, of which nucleus is made of, are positively charged particles. Actually nucleus is made of protons and neutrons but neutrons are uncharged particles.
2. Positive charge
Electric force between two electrons is same as electric force between two protons kept at same distance apart i. e., both set repel each other but electric force between an electron and proton placed at same distance apart is not repulsive but attractive in nature.
Basic properties of electric charge
| Property | Description |
|---|---|
| Additivity | Total charge equals algebraic sum of charges |
| Conservation | Charge can neither be created nor destroyed |
| Quantization | Charge exists in discrete units |
Additive property of electric charge
The electric charges are additive in nature having a scalar property and it depends upon the type of electric charge they carry.
It is possible to add them directly. e.g. let's consider a system containing only two charges q1 and q2.
According to this property, the total charge of the system can be calculated by algebraic sum of q1 and q2 means Q = q1 + q2.
Similarly now, a system contains q1, q2, q3, q4 - - - qn, then the net charge(Q) of the whole system can be :
Net Charge = q1 + q2 + q3 + q4 + - - - + qn
Conservative nature of electric charge
The electric charge of a particle is conservative in nature means that the charge can neither be created nor be destroyed.
The charges can be transferred from one system to another system by the mechanism like conduction and induction.
Conservative nature is similar to the law of conservation of mass and similar to the first law of thermodynamics (law of conservation of energy).
The Rubbing of two bodies involves a transfer of electrons from one body to another.
Quantization of Charge
The charge of a system is a fixed quantity means technically say that charge is a quantized quantity.
The net charge of a system can be expressed as the integral multiples of the basic unit of charge.
In 1912, The principle of the quantization of electric charge was first proposed by English scientist Faraday.
This proposal was based on his experimental laws of electrolysis and later this principle was demonstrated and proved by Millikan.
Examples of Electric Charges in Daily Life
- Rubbing a balloon on hair
- Static electricity in clothes
- Lightning during storms
- Attraction of paper by charged comb
Frequently Asked Questions
What are the basic properties of electric charge?
The basic properties of electric charge are additivity, conservation and quantization of charge.
What is quantization of charge?
Charge exists in discrete quantities and is always an integral multiple of elementary charge.
What is the SI unit of electric charge?
The SI unit of electric charge is Coulomb (C).
Who discovered quantization of charge?
Millikan experimentally proved quantization of charge using the oil drop experiment.