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AP EAMCET2005PhysicsElectrostatics

Two charges 2 C and 6 C are separated by a finite distance. If a charge of -4 C is added to each of them, the initial force of 12 10^3 ~N will change to

Options

  1. A4 10^3 ~N (repulsion)
  2. B4 10^2 ~N (repulsion)
  3. C6 10^3 ~N (attraction)
  4. D4 10^3 ~N (attraction)

Correct answer

D. 4 10^3 ~N (attraction)

Step-by-step solution

aligned & Initial force, F=k q₁ q₂ r^2 & F₁=k (2)(6) r^2 & New force, F₂=k (2-4)(6-4) r^2 =k (-2)(2) r^2 & F₁ F₂ = (2 6) (-2 2) & 12 10^3 F₂ =-3 & F₂=-4 10^3 ~N aligned Force is negative, so it will be of attraction.

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