Physics Electric charge,Definition and their types

Electric charge Definition:

                               The agent which endowses the property of attraction or repulsion in a body is called charge.OR   The tendency of a body to attract or repel any other body is called charge.So charge the intrinsic property of a body due to which it exert force on another body.The charges are of two types .

1. Positive charge .
2. Negative charge.

If a body is an excess of positive or negative charge this body is called charged body .This charged body posses the property of attraction or repulsion.

In  1600 AD Gilbert showed that some substances when rubbed with each other acquired the property of attracting light bodies. FOR EXAMPLE   When glass rod is rubbed with silk both then attract the small pieces of papers. similarly when ebonite rod is rubbed with flannel or animal far both electrify and hence posses the property of attracting small pieces of paper . Franklin gave the name positive charge on glass rod when rubbed with silk and gave the name negative charge on ebonite rod rubbed with flannel .The name given as positive charge or negative charge is merely a convention.

Ordinarily all the objects are electrically neutral because the have equal number of positive and negative charges.the positive charge in an atom is carry by proton present in the nucleus of an atom and the negative charge is carry by the electron revolving around the nucleus .The object can be electrified positive or negative by addition or removal of charges(electrons) .in the process of electrification charge can neither be created but only can transfer from one body to another body.which means that charge is conserved .For example when glass is rubbed with silk some of the negative charge will be transfer from glass to silk.There for the glass rod will be deficit of negative charge and electrified as positively . the silk on the other hand will be an excess of negative charge and it will be electrified as negatively.

The charge in the body exists in the discrete packets rather then continue amount .
This give the quantization of charge. Any charge q is an integral multiple of the minimum elementary charge e.

q = ne          Where e is quantum of charge which is very small .

Is experimentally found that .

• The like charges repel each other .
• The unlike charges attract each other .

The branch of physics which deals with the study of the properties of charges is called electricity. the electricity is divided into two branches.

1. Electrostatics .
2. Electrodynamics .

Electrostatics :

              The branch of electricity which deals with the study of the properties of charge at rest is called electrostatics.

Electrodynamics:

               The branch of electricity which deals with the study of properties of charges in motion is called electrodynamics.