Basic Qualification · B-005 Basic electronics and theory · B-005-012-005
When a parallel coil-capacitor combination is supplied with AC of different frequencies, there will be one frequency where the impedance will be highest. This is the:
- A resonant frequency
- B maximum frequency
- C inductive frequency
- D reactive frequency
Correct answer: A — resonant frequency. From the official ISED question bank, verified word for word.
Why
When a coil and capacitor sit side by side in a parallel circuit, they fight each other's effects at a specific pitch of alternating 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.