a point charge `q` is situated at a distance `r` from one end of a thin conduction rod of length `L` having a charge `Q` (uniformly distributed a long its length).find the magnitudes of electric force between the two.

Options

A. `(1)/(4piin_(0))(qQ)/(d(d+L))`
B. `(qQ)/(4piin_(0)d)`
C. `(qQ)/(2piin_(0)d)`
D. `(qQ)/(8piin_(0)d(d+L))`

Answer

A

Explanation

dF = `(kqdQ)/(x^(2))=(kq)/(x^(2))(Q)/(L)dx`
`F=overset(x=d+L)underset(x=d)intdF^(')`