Basic Qualification · B-004 Circuit components · B-004-006-002
On a resistor with four colour bands, what do the first three colour bands indicate?
- A The power rating in watts
- B The resistance tolerance in percent
- C The value of the resistor in ohms
- D The resistance material
Correct answer: C — The value of the resistor in ohms. From the official ISED question bank, verified word for word.
Why
The first three colour bands on a four-band resistor tell you the actual resistance value in ohms, which is the measure of how much the component opposes electric current. 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.