Answer: Due to unsymmetrical spacing, the magnetic field external to the conductor is not zero. Thereby causing induced voltage in adjacent electric circuits particularly the telephone lines that may cause disturbances in the telephone lines. Transposition of line conductor in transmission line is essential to counter the unbalancing effects of irregular spacing of line connector.
Answer: The basic definition for transposition of transmission line is to rotate the conductors which result in the conductor or a phase being moved to next physical location in a regular sequence. In electrical power transmission lines, the conductor arranges unequal space. So the voltage drops are not same as one place to another.
To eliminate this effect can simply do by interchange the conductor position which is known as transposition. When the transmission line is more than 100 km long, then, as per electrical requirements three phases needed to be transposed. The transposition arrangement is much necessary which there is a capacitance between the power conductor. When the high voltage applied capacitance created between the conductors and conductor and ground.