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KVPY2017PhysicsElectrostatics

The black shapes in the figure below are closed surfaces. The electric field lines are in red. For which case the net flux through the surfaces is non-zero?

Options

  1. AIn all cases net flux is non-zero
  2. BOnly (c) and (d)
  3. COnly (a) and (b)
  4. DOnly (b), (c) and (d)

Correct answer

C. Only (a) and (b)

Step-by-step solution

= q _ en ₀ q _ en is not zero for a and b . therefore flux ( ) is not zero.

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