Question

What is the dimension of electric field intensity?

(a) [M L T^-2 I^-1]

(b) [M L T^-3 I^-1]

(c) [M L T^-2 I^-2]

(d) [M L T^-3 I]

The question was posed to me in examination.

This is a very interesting question from Electric Field in chapter Charges and Fields of Physics – Class 12

Answer 1

Correct option is (b) [M L T^-3 I^-1]

Explanation: Electric field intensity is defined as the force on a unit positive charge kept in an electric field. Hence we can simply consider its dimension as\(\frac {the \, dimension \, of \, force}{the \, dimension \, of \, charge}\). The dimension of force is [MLT^-2] and the dimension of charge is [IT]. Therefore the dimension of field intensity is [M L T^-3 I^-1].