Question

Net charge within an imaginary cube drawn in a uniform electric field is always zero. Is this statement true or false.

Answer 1

Statement is true.
In a uniform electric field, the number of field lines entering the closed imaginary cube is equal to the number of field lines leaving the closed imaginary cube. Hence the total outwards electric flux through the closed imaginary cube is zero. By Gauss's Law , this means he enclosed charge within the closed imaginary cube is zero.