Electric charges are distributed in a small volume. The flux of the electric field through a spherical surface of radius 10 cm surrounding the total charge is 25 V m. The flux over a concentric sphere of radius 20 cm will be
Gauss’ law states that the electric flux through a closed surface is equal to 1/ϵ0 times the total charge enclosed by the surface.
,
where
Φ = electric flux
E = electric field
ds = area element
q = charge enclosed
∊0 = electric permittivity of vacuum
Hence, the flux depends on the charge enclosed.
In this case, even though the volume of the sphere enclosing the charge is increasing, the net charge enclosed inside it is remaining the same.
Hence, the electric field will remain the same = 25 V m. (Option a)
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