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AP EAMCET20224 Jul 2022Morning ShiftPhysicsElectrostaticsActual

Two positive point charges of 10 μC and 12 μC are placed 10 cm apart in air. The work done to bring them 6 cm closer is

Options

  1. A8 . 1   J
  2. B3 . 2   J
  3. C9   J
  4. D13 . 5   J

Correct answer

A. 8 . 1   J

Step-by-step solution

Work done = Increase in potential energy = K q 1 q 2 1 r 2 - 1 r 1 = 9 × 10 9 × 10 × 10 - 6 × 12 × 10 - 6 1 6 - 1 10 × 10 2 = 7 . 2   J Hence, the correct option is 8 . 1   J .

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