A positive charge 'Q' is fixed at a point A negatively charged particle of mass ' 'm' and charge 'q' is revolving in a circular path of radius `r_(1)` ,with Q' as the centre.The change in potential energy to change the radius of the circular path from `r_(1)` to `r_(2)` in joule is

Options

A. 0
B. `(Qq)/(4pi epsi_(0)) [(1)/(r_(1)) - (1)/(r_(2))]`
C. `(1)/(4pi epsi_(0)) (Qq)/(4pi epsi_(0)) [(1)/(r_(1)) - (1)/(r_(2))]`
D. `(Qq)/(4pi epsi_(0)) [(1)/(r_(2)) - (1)/(r_(1))]`

Answer

B

Explanation

`W = (q_(1) q_(2))/(4pi in_(0)) ((1)/(r_(1)) - (1)/(r_(2)))`