how are radio waves discovered?
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Heinrich Hertz proved the existence of radio waves in the late 1880s. He used a spark gap attached to an induction coil and a separate spark gap on a receiving antenna. When waves created by the sparks of the coil transmitter were picked up by the receiving antenna, sparks would jump its gap as well.
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Electromagnetic waves are produced whenever electric charges are accelerated. This makes it possible to produce electromagnetic waves by letting an alternating current flow through a wire, an antenna. The frequency of the waves created in this way equals the frequency of the alternating current.
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1) Electricity flowing into the transmitter antenna makes electrons vibrate up and down it, producing radio waves. 2) The radio waves travel through the air at the speed of light. 3) When the waves arrive at the receiver antenna, they make electrons vibrate inside it.
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Characteristics of electromagnetic waves Electromagnetic waves are transverse waves, similar to water waves in the ocean or the waves seen on a guitar string. This is as opposed to the compression waves of sound. As you learned in Wave Motion, all waves have amplitude, wavelength, velocity and frequency.
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Wireless networks operate using radio frequency (RF) technology, a frequency within the electromagnetic spectrum associated with radio wave propagation. When an RF current is supplied to an antenna, an electromagnetic field is created that then is able to propagate through space.
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All electromagnetic waves, from radio waves with wavelengths L~km to gamma-rays with L~10e-12 m (i.e. 1 picometre, or 1 pm), are made up of bundles of energy called `photons'. ... So EM radiation can show `classical' wave-like properties in some situations, and `classical' particle-like properties in others.
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['Microwaves.', 'X-ray.', 'Radio waves.', 'Ultraviolet waves.']
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Radio waves are a type of electromagnetic radiation with wavelengths in the electromagnetic spectrum longer than infrared light. ... Naturally occurring radio waves are emitted by lightning and astronomical objects. Radio waves are generated artificially by transmitters and received by radio receivers, using antennas.
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Stars and lightning are natural sources of radio waves, but these are also produced by the antenna on a radio transmitter. Many sources of electromagnetic radiation come from man-made technology. On the other side of the spectrum, we have ultraviolet radiation, which is emitted by black lights and fluorescent lamps.
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radio waves, microwaves, infrared waves, visible light, ultraviolet radiation, X-rays, and gamma rays.
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Radio waves are used for communication such as television and radio. Radio waves are transmitted easily through air. They do not cause damage if absorbed by the human body, and they can be reflected to change their direction. These properties make them ideal for communications.
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Radio waves are electromagnetic waves with the longest wavelengths, lowest frequencies, and least amount of energy. They are used for radio and television broadcasts and many other purposes. In radio broadcasts, sounds are encoded in radio waves by changing either the amplitude (AM) or frequency (FM) of the waves.
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['Radio waves.', 'Infra-red waves.', 'Microwaves.', 'None of the above.']
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Most electromagnetic radiation from space is unable to reach the surface of the Earth. Radio frequencies, visible light and some ultraviolet light makes it to sea level. Astronomers can observe some infrared wavelengths by putting telescopes on mountain tops.
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Radio waves. Radio waves are used for communication such as broadcasting television and radio, communications and satellite transmissions. Radio waves are transmitted easily through air. They do not cause damage if absorbed by the human body, and they can be reflected to change their direction.
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Definition: Electromagnetic waves or EM waves are waves that are created as a result of vibrations between an electric field and a magnetic field. ... Description: Electromagnetic waves are formed when an electric field comes in contact with a magnetic field. They are hence known as 'electromagnetic' waves.
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Electromagnetic waves are generated by accelerating (or oscillating) charges. The frequency of the wave simply depends on how fast the charge is oscillating.