Question

What do you mean by number density of free electrons??

Answer 1

Dear student,

Number of free electrons present per unit volume of a conductor is defined as the number density of free electrons of that conductor.
These free electrons are responsible for carrying current in a conductor.This value is used to find out current in a conductor from the formula I=nAeV_D,Where n=number density,A=area of cross section of conductor,e=charge of electron,V_D=Drift velocity.
Regards.