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JEE Main20258 Apr 2025Evening ShiftPhysicsElectrostaticsActual

Two metal spheres of radius R and 3 R have same surface charge density . If they are brought in contact and then separated, the surface charge density on smaller and bigger sphere becomes ₁ and ₂ , respectively. The ratio ₁ ₂ is.

Options

  1. A1 9
  2. B9
  3. C1 3
  4. D3

Correct answer

D. 3

Step-by-step solution

For conducting sphere, V = r ₀ After contact, V ₁= V ₂ aligned & ₁ r₁= ₂ r₂ & ₁ ₂ = r₂ r ₁ & ₁ ₂ =3 aligned

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