A dipole of dipole moment `vecp=phati` is kep at the centre of a circle of radius `r` as shown in the figure. The radius of the circle is very large in comparison to the distance between the two charges of the dipole. A & B are two points on the axis and C & D are two points on the equitorial line of the dipole if `V_(A),V_(B),V_(C)` and `V_(D)` are potentials at A,B,C and D respectively then, which of the following is correct?

Options

A. `V_(A)-V_(B)=0,V_(A)-V_(D)=(2kp)/(r^(2))`
B. `V_(A)-V_(B)=(2kp)/(r^(2)), V_(A)-V_(D)=(kp)/(r^(2))`
C. `V_(A)-V_(B)=0, V_(A)-V_(D)=(kp)/(r^(2))`
D. `V_(A)-V_(B)=(2kp)/(r^(2)), V_(A)-V_(D)=(2kp)/(r^(2))`

Answer

B

Explanation

`V_(C)=V_(D)=0`
`V_(A)=(kp)/(r^(2))`
`V_(B)=(kp)/(r^(2))`