Red Seal Electrician Practice
TransformersQuestion 1425 of 1506

A single-phase transformer has 500 turns on the primary and 1000 turns on the secondary. The primary is connected to 120 V. What is the secondary voltage?

  1. 120 V
  2. 139 V
  3. 240 V
  4. 416 V
Show answer

Correct answer: 240 V

Vs = Vp × (Ns ÷ Np) = 120 × (1000 ÷ 500) = 240 V.

Source: Computed, 1.1: What is Alternating Current (AC)?

Practice transformers

Questions last reviewed: 18 October 2026