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JEE Main202131 Aug 2021Evening ShiftPhysicsElectrostaticsActual

Choose the incorrect statement: (a) The electric lines of force entering into a Gaussian surface provide negative flux. (b) A charge q is placed at the centre of a cube. The flux through all the faces will be the same. (c) In a uniform electric field net flux through a closed Gaussian surface containing no net charge, is zero. (d) When an electric field is parallel to a Gaussian surface, it provides a finite non-zero

Options

  1. A(b) and (d) Only
  2. B(c) and (d) Only
  3. C(a) and (c) Only
  4. D(d) Only

Correct answer

D. (d) Only

Step-by-step solution

We know that electric flux is a scalar quantity and this is the scalar product of the magnitude of electric field and surface area. Recall, the formula given by Gauss theorem, ϕ = E → · A → = E A cos θ , here θ = 90 ° , it means, ϕ = 0 .

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