GATE Electrical Engineering (EE) 2016 Shift 1 Solved Paper

A single-phase transmission line has two conductors each of $10\mathit{m}\mathit{m}$ radius. These are fixed at a center-to-center distance of $1\mathit{m}$ in a horizontal plane. This is now converted to a three-phase transmission line by introducing a third conductor of the same radius. This conductor is fixed at an equal distance $\mathit{D}$ from the two single-phase conductors. The three-phase line is fully transposed. The positive sequence inductance per phase of the three-phase system is to be $5\%$ more than that of the inductance per conductor of the single-phase system. The distance $\mathit{D}$, in meters, is _______.