Radio waves are detected using electrical circuits that receive these electromagnetic signals in an antenna, and then the radio frequencies are modulated through capacitors before emerging as sound in a speaker. Radio waves are normally less than a kilohertz long up to 20 gigahertz. Since humans cannot hear these frequencies, radio signals are often translated into sounds by electrical devices.Continue Reading
Antennas that receive radio signals are generally the same size as the wavelength they are designed to receive. Wider antennas detect longer, or fainter, wavelengths. Communications antennas are usually one-quarter the size of the transmitter, especially with applications for automobiles, satellite television and cellular phones. Receiving antennas are smaller simply to save space while the transmitters are stronger so detection is easier.
In March 2014, the Niels Bohr Institute announced a new method to detect radio waves using lasers that operate at room temperature. Very low frequencies of radio waves are measured in very cold settings that are a few degrees above absolute zero to reduce background noise created by heat. Background noise distorts readings and measurement so the laser technology reduces any background noise and allows scientists to take more accurate measurements. Instead of resistors that read the capacitors in an electrical circuit, a laser interprets the capacitor's signal and turns the radio waves into light energy instead of sound.Learn more about Optics & Waves
In large doses, radio waves, also known as radio frequencies, can disrupt biological functions and break down tissue. There is still much debate over whether or not the radio frequencies emitted from mobile communication devices and the systems that support them pose any danger.Full Answer >
Radio waves are able to wirelessly carry important information almost instantaneously and, aside from just transmitting audio and television signals, they make cell phones, global positioning systems and space communication possible. Radio wave technology has allowed for significantly faster and easier communication and navigation.Full Answer >
When sound waves strike a surface, they reflect off of that surface and can return to the source of the sound as an echo. To a listener, this may be identical to the original sound, just delayed and possibly distorted by its path through the air. If the echo arrives quickly enough, it may seem to be part of the original sound, forming a reverberation instead of an echo.Full Answer >
Although both sound and light are fast by human standards, light is far faster than sound because waves of sound must propagate through a medium, while the speed of light is tied to fundamental universal constants. Light travels at about 300,000 kilometers per second, and the speed of sound is usually around 300 meters per second.Full Answer >