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A charged particle q is shot towards another charged particle Q which is fixed, with a speed v it approaches Q upto a closest distance r and then returns. If q were given a speed 2 v , the closest distances of approach would be

Options

  1. Ar
  2. B2 r
  3. Cr / 2
  4. Dr / 4

Correct answer

D. r / 4

Step-by-step solution

By principle of conservation of energy Finally, 1 2 m(2 v)^2= K q Q r^2 Equation (i) (ii), aligned & 1 4 = r^ r & r^ = r 4 . aligned

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