SignalPrep
Advanced Qualification · A-007 Feedlines and matching · A-007-004-008

The impedance of a half-wave antenna at its centre is low, because at this point:

  1. Avoltage is low and current is high
  2. Bvoltage and current are both high
  3. Cvoltage and current are both low
  4. Dvoltage is high and current is low

Correct answer: A — voltage is low and current is high. From the official ISED question bank, verified word for word.

Why

At the exact centre of a half-wave antenna, the electrical pressure, or voltage, drops to its lowest point while the flow of electricity, known as current, reaches its peak. The full explanation — and one for every question — is in Pro.

Practise this section

Feedlines and matching is section A-007 of the Advanced exam: Feedlines and matching at the advanced level: transmission line theory, impedance transformation, stubs and matching networks.

Drill A-007 — free, no account

Cette question en français · All A-007 questions