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MHT CET202520 Apr 2025Morning ShiftPhysicsElectrostaticsActual

A conducting sphere of radius ' R ' is given a charge ' Q ' uniformly. The electric field and the electric potential at the centre of the sphere are respectively [ ₀= permittivity of free space]

Options

  1. Azero and Q 4 ₀ R
  2. BQ 4 ₀ R^2 and zero
  3. CQ 4 ₀ R and Q 4 ₀ R^2
  4. Dzero and zero

Correct answer

A. zero and Q 4 ₀ R

Step-by-step solution

Electric Field at the Center For a conducting sphere in electrostatic equilibrium, all charge resides on its outer surface. Consider a Gaussian surface with radius r Electric Potential at the Center The potential is constant throughout a conductor. On the surface, V_ surface = Q / (4 ₀ R) , so the potential at the center is identical: V_ center = Q / (4 ₀ R) . The electric field is zero and the potential is Q / (4 ₀ R) , corresponding to option A .

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