Question

What is the unit of surface charge density in the SI unit?

(a) C

(b) C/m

(c) C/m^2

(d) C/m^3

The question was asked in an internship interview.

This question is from Basic Properties of Electric Charge topic in portion Charges and Fields of Physics – Class 12

Answer 1

Right option is (c) C/m^2

The explanation: Surface charge density means how much charge is stored in the unit surface area of a conductor. So, it’s unit will be=\(\frac{the \, unit \, of \, the \, charge}{the \, unit \, of \, area}\). In SI the unit of charge is Coulomb and the unit of area is m^2. Therefore the required unit will be C/m^2.