Question

In an electric field due to a point charge $+Q$ a spherical closed surface is drawn as shown by dotted circle. The electric flux through the surface drawn is zero by Gauss law. A conducting sphere is inserted intersecting the previously drawn Gaussian surface. The electric flux through the surface

• A. still remains zero
• B. non-zero and positive
• C. non-zero and negative
• D. becomes infinite

Answer 1

The correct option is B non-zero and positive

By induction a negative charge will induce on the sphere on the side facing the charge and a positive charge on the side farthest from the charge.

Charged enclosed in Gaussian surface is $+$ve, so $\varphi$ is positive