Charge is something possessed by material objects that make it possible for them to exert electrical force and to respond to electrical force.
There exists only two types of charges, namely positive and negative. Like charges repel and unlike charges attract each other. Charge is a scalar quantity.
An electron attack another electron place 1 cm apart because of gravitational force with 5.5x10-67 N, whereas it observed an electron repel another electron placed 1 cm apart because of electric force is 2.3x10-24 N. Since this repulsive force is very large as compare to attractive force of gravitation, there must be some additional property associated with electron.
This additional property of electron, which gives rise to electric force between two electron is called as electric charge.
When a body gets the static charge by any means then body is said to be electrified or charged. When it has no charge it is said to be neutral.
Fundamental Electronic Charge (e = 1.6 x 10-19 C). SI unit of charge is Coulomb ( C ) and is generally denoted by q.
Note: Recently, the existence of quarks of charge ⅓ e and ⅔ e has been postulated. If the quarks are detected in any experiment with concrete practical evidence, then the minimum value of ‘quantum of charge’ will be either ⅓ e or ⅔ e. However, the law of quantiation will hold good.
Some of these questions which may be asked in your Board Examination 2012-2013
Q1: What is a charge?
Q2: What is the SI unit of Charge?
Q3: What is charge on a neutron?
Q4: what is the change on an electron?
Q5: Explain what is an fundamental electronic charge?
Q6: what is main cause of charging?
Q7: Electrostatic forces are much stronger than gravitational forces. Give one example.
Q8: What is the value of charge on an electron? is a charge less than this value possible?
Q9: What is charge on a photon?
Answer these questions in comment box and help your friends