there will be no corona glow

corona glow will be uniform along the length of the conductor

there will be minimum power loss

hissing sound will be more intense

corona is voltage effect

corona takes place on short transmission lines

corona is accompanied with power loss

corona attenuates lightning surges

they have high potential difference

they are closely spaced

they carry D.C. power

they have high potential difference and they are closely spaced

increasing the operating voltage

reducing the spacing between conductors

increasing the effective conductor diameter

any of the above

Mean free length

Atmospheric temperature

Number of ions

Size and charge per ion