Propulsion AC generators creating 4160 VAC use transformers to provide nominally 120 VAC to the automatic voltage regulator. What is the turns ratio of this step-down transformer?

Correct Answer: Option C — 35:1

The turns ratio is determined by dividing the primary voltage by the secondary voltage. For a 4160V to 120V transformation, the ratio is 4160/120, which equals 34.66. Rounding to the nearest standard transformer specification provided in the options, 35:1 is the correct ratio for this voltage step-down application.