Basic Qualification · B-006 Feedlines and antenna systems · B-006-007-004
What electromagnetic wave polarization does a half-wavelength antenna have when it is perpendicular to the Earth's surface?
- A Horizontal
- B Elliptical
- C Vertical
- D Circular
Correct answer: C — Vertical. From the official ISED question bank, verified word for word.
Why
When a half-wavelength antenna stands straight up, perpendicular to the ground, the electric field of the radio wave it sends out also points up and down. The full explanation — and one for every question — is in Pro.
Practise this section
Getting the signal out: antennas, feedlines, SWR, baluns, matching, and why antenna length depends on frequency.