In the morning we get the latest news from an AM or FM radio, newsfeeds on our mobiles, the television; mobiles help us pay for small purchases throughout the day such as our coffee, baguette or parking meter using NFC contactless technology, they enable us to alert the authorities in case of an emergency police, fire brigade, ambulance ; and they also enable connected objects to communicate thanks to consumer devices such as Wi-Fi, Bluetooth, LORA, DECT… and of course private and professional communication.
They have become indispensable. Radio Waves using waves to communicate. As we communicate by voice, modulating the mechanical waves emitted by our vocal cords, great physicists such as Hertz, Tesla, Branly and Marconi understood that it was possible to use electromagnetic waves to convey information through the air.
Also, when radio waves are absorbed by a conductor , they create an alternating current. This electrical current has the same frequency as the radio waves. Information is coded into the wave before transmission, which can then be decoded when the wave is received.
Television and radio systems use this principle to broadcast information. Microwaves are used for cooking food and for satellite communications. High frequency microwaves have frequencies which are easily absorbed by molecules in food. The internal energy of the molecules increases when they absorb microwaves, which causes heating. Microwaves pass easily through the atmosphere, so they can pass between stations on Earth and satellites in orbit. Does electromagnetic radiation travel in waves?
What are some electromagnetic waves that are lower than visible light? What is the frequency of a electromagnetic wave with a wavelength of 1. What are the longest and shortest visible electromagnetic waves that humans experience?
Do all stars radiate heat energy, light energy, and electromagnetic waves? What electromagnetic waves travel the fastest? What electromagnetic waves have the longest wavelengths?
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