Two small spheres each carrying a charge $q$ are placed $r$ metre apart. If one of the spheres is taken around the other one in a circular path of radius $r$, the work done will be equal to
  • AForce between them $ \times \,r$
  • BForce between them $ \times \,2\pi r$
  • CForce between them $/\,2\pi r$
  • D
    Zero
Easy
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