Basic Qualification · B-005 Basic electronics and theory · B-005-004-010
What formula calculates the resistance of a circuit when the voltage and current are known?
- A R = E x I
- B R = E / I
- C R = I / E
- D R = E squared / I
Correct answer: B — R = E / I. From the official ISED question bank, verified word for word.
Why
To find resistance when you know voltage and current, 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.