Question

Give the SI unit of current density and its dimensional formula.

(a) Am^-2, [A^1L^-2]

(b) Am^2, [A^1L^2]

(c) Am^-1, [A^1L^-1]

(d) Am^1, [A^1L^1]

I have been asked this question during a job interview.

This interesting question is from Ohm’s Law topic in division Current Electricity of Physics – Class 12

Answer 1

Correct option is (a) Am^-2, [A^1L^-2]

The best explanation: Current density is the amount of charge flowing per second through a unit area.

The SI unit of current density is ampere per square metre (Am^-2) and its dimensions are [A^1L^-2].