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JEE Main 202131 AugustEvening Shift
Exam
JEE Main
Year
2021
Date
31 August
Shift
Evening Shift
Subject
Physics
Chapter
Electrostatics

JEE Main 2021 · 31 August · Evening Shift · Physics · Electrostatics

Choose the incorrect statement: (a) The electric lines of force...

Choose the incorrect statement:
(a) The electric lines of force entering into a Gaussian surface provide negative flux.
(b) A charge qq 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 flux.

Choose the most appropriate answer from the options given below:

Choose the incorrect statement: (a) The electric lines of force entering into a Gaussian surface provide negative flux.

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.

Choose the incorrect statement: (a) The electric lines of force entering into a Gaussian surface provide negative flux.

Recall, the formula given by Gauss theorem, ϕ=E→⋅A→=EAcosθϕ = \overset{\to}{E} \cdot \overset{\to}{A} = EAcos\theta, here θ=90°\theta = 90 °, it means, ϕ=0ϕ = 0.

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