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radio wave
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radio waves
How does a radio convert waves into sound?
Figure 1: The electromagnetic spectrum. Schematic diagram showing the propagation of high-frequency (shortwave) radio waves by reflection off the ionosphereSpecific ionization conditions vary greatly between day (left) and night (right), causing radio waves to reflect off different layers of the ionosphere or transmit through them, depending upon their frequency and their angle of transmission. Under certain conditions of location, ionization, frequency, and angle, multiple “skips,” or reflections between ionosphere and Earth, are possible. At night, with no intervening layers of the ionosphere present, reflection off the F layer can yield extremely long transmission ranges. Diagram showing how radio waves travel beyond the horizon: one path follows the Earth's surface as a ground wave, while another, the sky wave, bounces off the ionosphere and returns to Earth. Diagram of the electromagnetic spectrum with labeled sections for radio waves, microwaves, infrared, visible light, ultraviolet, X-rays, and gamma rays, each paired with an example use and corresponding image.
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Italian-born physicist Dr. Enrico Fermi draws a diagram at a blackboard with mathematical equations. circa 1950.
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radio wave: References & Edit History

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Article History

Type Description Contributor Date
Invalidated site: Mustansiriyah University - Radio Wave Propagation in the Ionosphere (PDF). Aug 12, 2026
Add new Web site: Physics LibreTexts - Propagation of Radio Waves and Thermal Emission. Mar 05, 2026
Add new Web site: NYU Tisch School of the Arts - ITP Physical Computing - Radio Waves. Nov 05, 2025
Add new Web site: AIP Publishing - Physics Today - The many uses of radio waves. Apr 17, 2025
Add new Web site: Mustansiriyah University - Radio Wave Propagation in the Ionosphere (PDF). Jan 07, 2025
Add new Web site: USC Viterbi School of Engineering - Catch a Wave: Radio Waves and How They Work. Jul 26, 2024
Add new Web site: Harvard University - Harvard Natural Sciences Lecture Demonstrations - Radio Wave Properties. Aug 22, 2023
Add new Web site: NASA Science - Radio Waves. Apr 04, 2023
Media added. Apr 09, 2020
Add new Web site: Science with Kids - Facts About Radio Waves. Apr 03, 2019
Add new Web site: LiveScience - What are radio waves? Oct 27, 2017
Added "(For a fuller treatment, see also electromagnetic radiation: Radio waves.)" Jun 26, 2017
Added new Web site: Window To The Universe - Radio Waves. May 11, 2009
New article added. Mar 17, 2009
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