Search results
Results from the WOW.Com Content Network
The global electromagnetic resonance phenomenon is named after physicist Winfried Otto Schumann who predicted it mathematically in 1952. Schumann resonances are the principal background in the part of the electromagnetic spectrum [2] from 3 Hz through 60 Hz [3] and appear as distinct peaks at extremely low frequencies around 7.83 Hz (fundamental), 14.3, 20.8, 27.3, and 33.8 Hz.
The dispersion characteristics of the Earth-ionospheric waveguide can be used for locating thunderstorm activity by measurements of the difference of the group time delay of lightning signals at adjacent frequencies up to distances of 10000 km. [7] The Schumann resonances allow to determine the global lightning activity.
Main gases of the ionosphere (about 50 km; 31 miand above on this chart) vary considerably by altitude. The F layer or region, also known as the Appleton–Barnett layer, extends from about 150 km (93 mi) to more than 500 km (310 mi) above the surface of Earth. It is the layer with the highest electron density, which implies signals penetrating ...
The fundamental Schumann resonance is at approximately 7.83 Hz, the frequency at which the wavelength equals the circumference of the Earth, and higher harmonics occur at 14.1, 20.3, 26.4, and 32.4 Hz, etc. Lightning strikes excite these resonances, causing the Earth–ionosphere cavity to "ring" like a bell, resulting in a peak in the noise ...
However, resonance can also be detrimental, leading to excessive vibrations or even structural failure in some cases. [3] All systems, including molecular systems and particles, tend to vibrate at a natural frequency depending upon their structure; this frequency is known as a resonant frequency or resonance frequency.
Winfried Otto Schumann (May 20, 1888 – September 22, 1974) was a German physicist and electrical engineer who predicted the Schumann resonances, a series of low-frequency resonances caused by lightning discharges in the atmosphere.
For premium support please call: 800-290-4726 more ways to reach us
Radio waves (black) reflecting off the ionosphere (red) during skywave propagation. Line altitude in this image is significantly exaggerated and not to scale. In radio communication, skywave or skip refers to the propagation of radio waves reflected or refracted back toward Earth from the ionosphere, an electrically charged layer of the upper atmosphere.