An ideal transformer has 480 volts applied to its primary and a primary-to-secondary turns ratio of 4:1. What secondary voltage is expected?
- A480 volts
- 120 volts
- C4 volts
- D1,920 volts
Where to look it up
Explicit exercise assumptions; not a universal code requirement.
Why B is correct
Vs/Vp = Ns/Np = 1/4, so Vs = 480/4 = 120 volts. The result uses the stated primary-to-secondary turns ratio and the ideal-transformer assumption.