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NEET2026PhysicsChapterActual

A closed Gaussian surface contains no net charge, while some point charges are situated outside it. Which of the following is a correct deduction regarding the electric field E and the net electric flux through the surface?

Options

  1. AThe electric field E must be zero at all points on the surface.
  2. BThe net electric flux is zero, but E at the surface need not be zero.
  3. CThe external charges will produce a non-zero net electric flux through the surface.
  4. DThe electric field E at any point on the surface is independent of the external charges.

Correct answer

B. The net electric flux is zero, but E at the surface need not be zero.

Step-by-step solution

According to Gauss's Law, the net electric flux through a closed surface is given by = E d A = q_ in ₀ . Since the net charge enclosed by the Gaussian surface is zero ( q_ in = 0 ), the net electric flux through the surface must be zero. The electric field E at any point on the surface is the resultant field due to all charges present in space, both inside and outside the surface. Since there are point charges situated outside the surface, they will produce an electric field at points on the surface. Thus, the elec

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