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Can you list the top facts and stats about Radio waves?
Summarize this article for a 10 year old
Radio waves are a type of electromagnetic radiation with the lowest frequencies and the longest wavelengths in the electromagnetic spectrum, typically with frequencies of 300 gigahertz (GHz) and below. At 300 GHz, the corresponding wavelength is 1mm, which is shorter than the diameter of a grain of rice. At 30 Hz the corresponding wavelength is ~10,000 kilometers (6,200 miles), which is longer than the radius of the Earth. Wavelength of a radio wave is inversely proportional to its frequency, because its velocity is constant. Like all electromagnetic waves, radio waves in a vacuum travel at the speed of light, and in the Earth's atmosphere at a slightly slower speed. Radio waves are generated by charged particles undergoing acceleration, such as time-varying electric currents. Naturally occurring radio waves are emitted by lightning and astronomical objects, and are part of the blackbody radiation emitted by all warm objects.
Radio waves are generated artificially by an electronic device called a transmitter, which is connected to an antenna which radiates the waves. They are received by another antenna connected to a radio receiver, which processes the received signal. Radio waves are very widely used in modern technology for fixed and mobile radio communication, broadcasting, radar and radio navigation systems, communications satellites, wireless computer networks and many other applications. Different frequencies of radio waves have different propagation characteristics in the Earth's atmosphere; long waves can diffract around obstacles like mountains and follow the contour of the Earth (ground waves), shorter waves can reflect off the ionosphere and return to Earth beyond the horizon (skywaves), while much shorter wavelengths bend or diffract very little and travel on a line of sight, so their propagation distances are limited to the visual horizon.
To prevent interference between different users, the artificial generation and use of radio waves is strictly regulated by law, coordinated by an international body called the International Telecommunication Union (ITU), which defines radio waves as "electromagnetic waves of frequencies arbitrarily lower than 3,000 GHz, propagated in space without artificial guide". The radio spectrum is divided into a number of radio bands on the basis of frequency, allocated to different uses.
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WikiWand AI, hebu tufanye kazi kwa haraka na kujibu maswali haya muhimu: Je, unaweza kuorodhesha ukweli na takwimu za juu kuhusu mawimbi ya redio? Mawimbi ya redio ni aina ya mnururisho wa umeme na masafa ya chini na urefu wa mawimbi katika wigo wa umeme, kwa kawaida na masafa ya gigahertz 300 na chini. Kwa kiwango cha GHz 300, urefu wa wimbi unaolingana ni 1mm, ambayo ni fupi kuliko kipenyo cha chembe ya mchele. Kwa 30 Hz, urefu wa wimbi unaolingana ni ~ 10,000 km, ambayo ni ndefu kuliko kipenyo cha Dunia. Urefu wa wimbi la redio unalingana na mzunguko wake, kwa sababu mwendo wake ni wa kawaida. Kama mawimbi yote ya umeme, mawimbi ya redio katika utupu husafiri kwa mwendo wa mwanga, na katika angahewa la Dunia kwa mwendo wa polepole kidogo. Mawimbi ya redio hutokezwa na chembechembe zenye nishati zinazopigwa na mwendo, kama vile mikondo ya umeme inayobadilika-badilika kwa muda. Mawimbi ya redio hutolewa na umeme na vitu vya angani, na ni sehemu ya mnururisho wa mwili mweusi unaotokana na vitu vyote vya joto. Mawimbi ya redio hutengenezwa kwa njia ya bandia na kifaa cha elektroniki kinachoitwa transmitter, ambacho huunganishwa na antena ambayo hutokeza mawimbi. Zinatolewa na antena nyingine iliyounganishwa na kipokeaji cha redio, ambacho hutengeneza ishara inayopokelewa. Mawimbi ya redio hutumiwa sana katika teknolojia ya kisasa kwa mawasiliano ya redio ya kudumu na ya rununu, utangazaji, rada na mifumo ya urambazaji wa redio, satelaiti za mawasiliano, mitandao ya kompyuta isiyo na waya na matumizi mengine mengi. Mawimbi ya redio ya masafa marefu yanaweza kuenea kwa njia tofauti katika anga ya dunia, mawimbi marefu yanaweza kuenea kwa njia tofauti, mawimbi mafupi yanaweza kuonekana kwenye anga ya ionosphere na kurudi duniani, wakati mawimbi mafupi yanaweza kuenea kwa njia tofauti. "Kwa hivyo, kwa sababu ya hali ya hewa, matumizi ya mawimbi ya redio yanapaswa kuwa chini ya sheria, na kwa hivyo, kwa mujibu wa sheria ya kimataifa ya Umoja wa Kimataifa wa Mawasiliano (ITU), mawimbi ya redio ni ""ngurumo za umeme za masafa ya chini ya 3,000 GHz, zinazosambazwa katika nafasi bila mwongozo wa bandia.""" Radio spectrum imegawanywa katika idadi ya bendi za redio kwa msingi wa mzunguko, iliyotengwa kwa matumizi tofauti. Oops kitu kilienda vibaya: