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
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
- A
Force between them $ \times \,r$
- B
Force between them $ \times \,2\pi r$
- C
Force between them $/\,2\pi r$
- D
Zero
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