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JEE Main202125 Feb 2021Evening ShiftPhysicsElectrostaticsActual

A charge q is placed at one corner of a cube as shown in figure. The flux of electrostatic field E → through the shaded area is:

Options

  1. Aq 8 ε 0
  2. Bq 24 ε 0
  3. Cq 48 ε 0
  4. Dq 4 ε 0

Correct answer

B. q 24 ε 0

Step-by-step solution

flux through cube = q 8 ϵ 0 flux through surfaces A B E H , A D G H , A B C D will be zero ϕ E F G H = ϕ D C F G = ϕ E B C F = 1 3 q 8 ϵ 0 = q 24 ϵ 0

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