TransformersQuestion 903 of 1506

A step-down transformer has 400 primary turns and 100 secondary turns. The primary current is 4 A. What is the secondary current?

1 A
16 A
4 A
0.25 A

Show answer

Correct answer: 16 A

The turns ratio is 4 to 1, so the current rises by 4 times: 4 A × 4 = 16 A.

Source: Lessons in Electric Circuits II: AC (Kuphaldt), 1.1: What is Alternating Current (AC)?

Questions last reviewed: 18 October 2026

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