A short electric dipole has a dipole moment 15×10−8 C−m. A point charge of 10 μC is placed at a distance of 10 cm on the dipole axis from the centre of the dipole. Then potential energy stored on the charge-dipole system is

Potential at the point due to the dipole, V=14π∈0pr2=9×109×15×10-8(0.1)2 volt                                                                                      =135×103 volt∴ Electro static potential energy stored in the system =VQ=135×103×10×10−6 J=1.35  J