If `oint_(s) E.ds = 0` Over a surface, then

Options

A. the electric field inside the surface and on it is zero.
B. the electric field inside the surface is necessarily uniform.
C. the number of flux lines entering the surface must be equal to the number of flux lines leaving it
D. all charges must necessarily be outside the surface.

Answer

C

Explanation

For `oint_"closed surface" vecE. dvecS=0` it is possible that electric flux is positive for some part and negative for some other part having the same magnitude so that total becomes zero. If electric lines are emerging out from the surface then electric flux is said to be positive and if electric lines enter into the surface then the flux is said to be negative. From Gauss.s law, the net enclosed charge within the surface must be zero for electric flux to become zero. There may be charges inside Gaussian surface but that must be positive and negative charges both having the same magnitude.