Basic Qualification · B-005 Basic electronics and theory · B-005-011-007
A transformer primary winding consumes 10 watts. Neglecting losses, if the secondary voltage is 5 volts, what is the secondary current?
- A2 amperes
- B0.5 amperes
- C1 ampere
- D5 amperes
Correct answer: A — 2 amperes. From the official ISED question bank, verified word for word.
Why
Since the transformer has no losses, the power going in equals the power coming out, meaning the secondary side must also deliver 10 watts. The full explanation — and one for every question — is in Pro.
Practise this section
Basic electronics and theory is section B-005 of the Basic exam: The theory: Ohm's law, power, series and parallel circuits, AC and DC, frequency and wavelength, decibels, and the metric prefixes the exam leans on.
Drill B-005 — free, no account