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Most Important Selected Qs for JEE AdvancedPhysicsElectrostatics

A thin semi-circular ring of radius r has a positive charge q distributed uniformly over it. The net field E at the centre O is

Options

  1. Aq 4 ^2 ₀ r^2 j
  2. B- q 4 ^2 ₀ r^2 j
  3. C- q 2 ^2 ₀ r^2 j
  4. Dq 2 ^2 ₀ r^2 j

Correct answer

C. - q 2 ^2 ₀ r^2 j

Step-by-step solution

aligned & Linear charge density = ( q r ) & aligned E & = d E (- j )= K d q r^2 (- j ) E & = K r^2 q r r d (- j ) & = K r^2 q ₀^ (- j )= q 2 ^2 ₀ r^2 (- j ) aligned aligned

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