14 Answer the following questions based on case study Potential due to an electric dipole The electric field of a dipole at a point with position vector r depends not just the magnitude r but also on the angle between r and p Further the field falls off at large distance not as 1 r typical of the field produced by a point charge but as 1 r The electric field obeys the superposition principle Since potential is related to the work done by the field electrostatic potential also follows the superposition principle The important contrasting features of electric potential of a dipole from that due to a single charge are a The potential due to a dipole depends not just on r but also on the angle between the position vector r and the dipole moment vector p It is however axially symmetric about p That is if you rotate the position vector r about p keeping e fixed the points corresponding to P on the cone so generated will have the same potential as at P b The electric dipole potential falls off at large distances as 1 r not as 1 r characteristic of the potential due to a single charge Potential due to an electric dipole 2a i The potential due to a dipole plane 0 0 x is a Directly proportional to r and zero respectively b Inversely proportional to r and zero respectively P c Both varies as V 40 12 d None of the above ii Two charges 10 C and 10 8 C are located 15 cm apart At what distance on the line joining the two charges inside the system is electric potential zero Take the potential at infinity to be zero a 15 cm b 7 5 cm c 9 0 cm