By Jolie Smith
What starts an electromagnetic wave?
A vibrating electric charge creates an EM wave. In other words, a charged object, made from particles with opposite charges meeting, with a nonzero acceleration (is not steadily moving) is able to create electromagnetic waves.
EM Waves vs. Mechanical Waves
Mechanical waves require a medium to travel through while electromagnetic waves do not travel through mediums but instead travel through a vacuum.
Mechanical waves are caused by wave amplitude or the elasticity of the medium through which it passes and not by frequency, while electromagnetic waves are produced by the vibration of the charged particles.
Radio stations emit sounds radio waves that are captured by your radio and bring wavelengths that make music.
Cellular phones use radio waves to transmit sound, though they are much smaller waves than AM or FM radio waves.
On a much different scale, radio waves are also emitted by stars and gases in space.
Radio waves have the longest wavelength and the lowest frequencies and energies on the electromagnetic spectrum. They have frequencies anywhere from 300 GHz to as low as 3 kHz, wavelengths from 1 millimeter to 100 kilometers, and energy of any amount less than10^-5.
Microwaves have the 2nd longest wavelengths and 2nd lowest frequencies and energy on the spectrum, with a range of 10 to 0.01 centimeters in length, 3 x 10^3 to 0.0 Hz in frequency, 10^5 to 0.0 in electronvolts.
Infrared waves are specific light waves that are emitted by our skin and objects with heat.
Night vision goggles can pick up these light waves. Fast food restaurants utilize infrared radiation from special lamps that help cook their food; TV remotes also use infrared waves to connect to the T.V. In addition, infrared light can assist astronomers in finding and mapping the dust between stars in space.
Infrared waves have the third highest wavelengths and third lowest frequencies and energy amounts, with a range of 0.01 to 7 x 10^5 centimeters in length, 3 x 10^12 to 4.3 x 10^14 Hz, and 0.01 to 2 eV.
Visible light waves
Visible light waves are the light waves we can see with our naked eyes. Fireflies and light bulbs emit visible light. The wavelength of these waves separate them into different colors that we perceive. Stars in outer space also emit visible light waves.
Visible light waves are the middlemen of the electromagnetic spectrum, having the fourth longest wavelengths and fourth lowest frequency and energy, with ranges of 7 x 10^-5 to 4 x 10^-5 centimeters, 4.3 x 10^14 to 7.5 x 10^14 Hz, and 2-3 eV.
Ultraviolet radiation is the strong radiation emitted by the Sun and is cause for skin burns and tans additionally to providing the necessary radiation/light for plants to grow on Earth. Additionally, ultraviolet radiation is used in hospitals through UV lamps that sterilize the equipment and surrounding air.
Ultraviolet radiation contains the third smallest wavelengths, while having the third highest frequency and energy, with ranges of 4 x 10^-5 to 10^-7 centimeters, 7.5 x 10^14 to 3 x 10^17 Hz, and 3 to 10^3 eV.
X-ray radiation is frequenty used in hospitals, doctor's offices, dental offices, and airport security clearances. X-ray waves are able to penetrate substances with the strong radiation and therefore display images of inner contens, such as one's bone structure. Additionally, hot gases emit x-rays in space.
X-ray radiation has the second shortest wavelengths and second highest frequency and energy, with wavelengths of 10^-7 to 10^-9 centimeters, frequencies of 3 x 10^17 to 3 x 10^19 Hz, and energies of 10^3 to 10^5 eV.
Gamma rays have the shortest wavelengths and highest frequency and energy, with wavelengths of 10^-9 centimeters, frequencies of less than 3 x 10^19 Hz, and energies less than 10^5 eV.
NASA explores the science of gamma rays and their extraordinary presence in our universe