What is the velocity factor of a transmission line?

The velocity factor (VF) of a transmission line is a fractional measure of how fast radio frequency energy travels through it compared to the speed of light in a vacuum. It is mathematically defined as the velocity of a wave in the line divided by the velocity of light in a vacuum (v/c). Because nothing can travel faster than light in a vacuum, this value is always a decimal less than 1 (or less than 100%). Distractors involving characteristic impedance or termination impedance are incorrect because those relate to the line's electrical opposition to current flow and SWR, not the physical speed of the wave. The option suggesting multiplication is mathematically inverted and would result in an impossibly large number.