A point negative charge -Q is placed at a distance r from a dipole with dipole moment P in the xy plane as shown in fig. The x-component of force acting on the charge-Q is

Options

A. `-(pKQ)/(r) cos theta hat(i) `
B. `(pKQ)/(r) cos theta hat(i)`
C. `-(2pKQ)/(x^(3)) cos theta hat(i)`
D. `(2pkQ)/(x^(3)) cos theta hat(i)`

Answer

C

Explanation

`overline E_1=(2 kp cos theta)/r^3 i`

`overlineF_x=-Q overline E_1=(-2 kp Q)/r^3 cos theta hat i`