Q.

For a short dipole placed at origin O, the dipole moment P is along x-axis, as shown in the figure. If the electric potential and electric field at A are V0 and E0, respectively, then the correct combination of the electric potential and electric field, respectively, at point B on the y-axis is given by          [2025]

1 V02 and E016  
2 zero and E08  
3 zero and E016  
4 V0 and E04  

Ans.

(3)

At point A (axial)

|E0|=2kpr3, V0=kpr2

At point B (equatorial)

|E|=kp(2r)3=E016

V = 0.