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MHT CET202012 Oct 2020Evening ShiftPhysicsElectrostaticsActual

A metal sphere of radius 'R' cm is charged with 4 C situated in air. If ' ' is surface density of charge , 'E' is electric intensity at a distance 'r' from the centre of sphere then 'r' is ( ₀= . permittivity of free space)

Options

  1. AR ₀ E
  2. BR ₀ E
  3. C₀ E R
  4. DR ₀ E

Correct answer

B. R ₀ E

Step-by-step solution

E = 1 4 ₀ q r ² ; = q 4 R ² q =4 R ² E = 1 4 ₀ 4 R ² r ² r²= R² ₀ E r=R ₀ E

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