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If oint(s)vecE.vecdS=0 over a surface, t...

If `oint_(s)vecE.vecdS=0` over a surface, then

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.

Text Solution

Verified by Experts

The correct Answer is:
C, D
`oint_(s)vecE.vec(dS)=0` shows that flux on the surface is zero.
`ointvecE.vec(dS)=0` Means no. of electric field lines emerge out is equal to no. of electric field lines emerge in. According to Gauss.s law, charge enclosed by the surface should be zero. Hence, other charges should be outside the surface as they are not considered in flux.
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