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Figure shows a rod A B , which is bent in a 120 ° circular arc of radius R . A charge ( - Q ) is uniformly distributed over rod AB . What is the electric filed E → at the centre of curvature O ?

Options

  1. A3 3 Q 8 π 2 ε 0 R 2   i ^
  2. B3 3 Q 8 π ε 0 R 2   i ^
  3. C- 3 3 Q 8 π 2 ε 0 R 2   i ^
  4. D3 3 Q 16 π 2 ε 0 R 2   i ^

Correct answer

A. 3 3 Q 8 π 2 ε 0 R 2   i ^

Step-by-step solution

δ = 2 k λ R sin θ 2 i ^ = 2 k R Q 2 R π 3 sin 60 ° i ^ = 3 k Q π R 2 3 2 i ^ = 3 3 2 π kQ R 2 i ^

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