Basic Qualification · B-004 Circuit components · B-004-006-003
On a resistor with four colour bands, what does the fourth colour band indicate?
- A The power rating in watts
- B The resistance material
- C The resistance tolerance in percent
- D The value of the resistor in ohms
Correct answer: C — The resistance tolerance in percent. From the official ISED question bank, verified word for word.
Why
The fourth colour band on a four-band resistor tells you how much the actual resistance might differ from the printed value, expressed as a percentage. The full explanation — and one for every question — is in Pro.
Practise this section
The parts inside the box: resistors, capacitors, inductors, diodes, transistors, tubes and what each does in a circuit.