Mention characteristics of electric field

Explanation

Characteristics of electric field is as following :
(i) The charge Q, which is producing the electric field is called a source charge and the charge q, which tests the effect of a source charge is called a test charge.
However, if a charge q is brought at any point around Q, Q itself is bound to experience an electrical force due to q and will tend to move. A way out of this difficulty is to make q negligibly small. The force `vecF` is then negligibly small but the ratio `F/q` is finite and defines the electric field:
`vecE = "lim"_(q=0) vecF/q`
(ii) Note that the electric field `vecE` due to Q though defined operationally in terms of some test charge q is independent of q. This is because `vecF` is proportional to q, so the ratio `F//q` does not depend on q.
The field exists at every point in three-dimensional space.
(iii) For a positive charge, the electric field will be directed radially outwards from the charge as shown in figure (a).

For a negative charge, electric field vector at each point, points radially inwards as shown in figure (b).

(iv) Since the magnitude of the force `vecF` on charge q due to charge Q depends only on the distance r of the charge q from charge Q the magnitude of the electric field `vecE` will also depend only on the distance r.
`therefore E prop 1/r^(2)`
Electric field produced by point charge has spherical acceptance.
(v) The direction of electric force on unit charge at any point is considered as the direction of electric field.
(vi) Faraday gave the first idea about electric field.