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KVPY2014PhysicsElectrostatics

Two equal charges of magnitude Q each are placed at a dictance d apart. Their electrostatic energy is E. A third charge -Q/2 is brough midway betway these two charges. The electrostatic energy of the system is now

Options

  1. A-2E
  2. B- E
  3. C0
  4. DE

Correct answer

B. - E

Step-by-step solution

_ i = k Q² d =E _ f = k Q² d + k(-Q)² d + k-Q² d aligned Q^ aligned =- k Q² d =-E

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