Electric charge

Matter consists of many (more than 100) fundamental particles. Three out of them are most important, namely electron, proton and neutron. There masses are

⇒ m_e = 9.1 x 10^-31
⇒ m_p ≈ m_n = 1.6 x 10^-27

These particles will attract each other due to gravitational forces.

⇒ This gravitational forces acts upon it according to the Newton's universal law of gravitation.

⇒ At the same time there also acts another force of repulsion between them. This force, in addition to the gravitational force is the electric force.

⇒ The fundamental intrinsic property due to which such a force acts is called the electric charge.

⇒ Charges are of two types. Any one of them is considered positive and the other negative.

⇒ Traditionally charge of proton is considered positive and that on an electron negative.

⇒ The force acting between the like charges is repulsive and it is attractive between two unlike charges.

⇒ In any substance electrons are comparatively weakly bounded thus when there is exchange of charge between two bodies, electrons are transferred from one body to another.

⇒ Coulomb is the SI unit of the quantity of charge and is represented by C.

⇒ The Quantity of charge passing in 1 second, through any cross section of a conductor carrying 1 ampere current is called 1 coulomb .

⇒ The magnitude of charge on an electron and on a proton is 1.6 x 10^-19
⇒ Electric charge, like mass is a fundamental property which is difficult to define.