Advanced Qualification · A-007 Feedlines and matching · A-007-008-010
If the ohmic resistance of a half-wave dipole is 2 ohms, and the radiation resistance is 72 ohms, what is the antenna efficiency?
- A97.3%
- B74%
- C72%
- D100%
Correct answer: A — 97.3%. From the official ISED question bank, verified word for word.
Why
Antenna efficiency measures how much power turns into radio waves instead of heat. 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