Question

If potential V = 20/(x^2 + y^2). The electric field intensity for V is

(a) /(x^2 + y^2)^2. State True/False.

(b) True

(c) False

I got this question during an interview.

My question is based upon Relation of E,D,V in chapter Electrostatic Fields of Electromagnetic Theory

Answer 1

The correct option is (a) /(x^2 + y^2)^2. State True/False.

The explanation is: E = -Grad (V) = -Grad(20/(x^2 + y^2)) = -(-40x i /(x^2 + y^2)^2 – 40(y j)/(x^2 + y^2)^2) = 40(x i + y j)/(x^2 + y^2)^2. Thus the statement is true.