Basic Qualification · B-005 Basic electronics and theory · B-005-004-005
What is the resistance of a circuit that draws 0.25 amperes from a 12-volt source?
- A 0.25 ohms
- B 48 ohms
- C 3 ohms
- D 12 ohms
Correct answer: B — 48 ohms. From the official ISED question bank, verified word for word.
Why
To find the resistance, you divide the voltage by the current. The full explanation — and one for every question — is in Pro.
Practise this section
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.