The Electromagnetic Spectrum
Forms of Radiation
Electromagnetic Waves
Electromagnetic (EM) waves are disturbances in electrical or magnetic fields. Unlike mechanical waves, EM waves do not require a medium to travel through, even traveling through the vacuum of space. EM waves also travel faster, as mechanical waves are based on amplitude and EM waves are based on rapid vibration.
The Electromagnetic Spectrum
Electromagnetic waves have a wide range of existence. EM waves vary from low frequency, long wavelength radio waves to high frequency, short wavelength gamma rays and cosmic rays.
Radio Waves
A wide range of the spectrum, radio waves are the weakest electromagnetic waves. They are used to transmit messages over long distance with radios and give information to make music and visuals. This radiation also is made by stars.
Microwaves
Microwaves are stronger than radio waves with higher frequency and smaller size. As suggested by the name, microwaves are used in microwaves to quickly heat our food. They also are used by astronomers to observe the structure of nearby galaxies.
Infrared Light
Infrared radiation in the embodiment of heat. It can be detected with night-vision goggles to detect centers of thermal energy such as a deer in the night. Infrared waves are also used by TV remotes to communicate with a television.
Visible Light
This tiny part of the spectrum is what allows us to see. Everything from fireflies to light bulbs to stars make visible light, which can be detected by anything with light receptors.
Ultraviolet Light
Ultraviolet radiation is what makes sunburns happen. Although harmful in that case, it can be used to sterilize surgical tools and the like. This light also allows the human body to produce Vitamin D.
X-Ray
X-rays are powerful light waves. They're small enough to be used to see into objects such as the human body. In hospitals, X-Rays can be used to observe potential injuries to bones, as bones reflect X-Rays, and airports use them in security scanners for detecting metal objects.
Gamma Rays and Cosmic Waves
Gamma rays and Cosmic rays are the most powerful EM waves. With the highest frequency, smallest size, and shortest wavelength, gamma rays are used in medical practice in the form of PET scans, which can display images of inside of the body. They also can be found most everywhere in space, as stars, supernovas, and the Universe create them.
What is the Electromagnetic Spectrum?