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ArcticMyst Security by Avery

(Information) What is the Electromagnetic Spectrum?

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Let me first start off by saying that I've always had an interest in learning about the medical field & how different wavelengths of lights work, affect the body and respond to things in the environment which gave me the idea to create this thread since I believe anyone else who is interested or curious in this stuff should have it easily accessible if they happen to be browsing on LPF! :)

I realize this information can easily be found online but realizing this is a laser forum filled with people who enjoy the same stuff I do(mostly) this is something which just makes sense to have. Plus, the more knowledge & information on here the better & smarter we become!

Without anymore delays, let's get started into this thing called the ELECTROMAGNETIC SPECTRUM:



ELECTROMAGNETIC SPECTRUM
What is the Electromagnetic Spectrum? The Electromagnetic Spectrum is very simple once you get to know it, honestly, it really is! This spectrum lists the range of all possible frequencies of Electromagnetic Radiation, which include: [radiowaves]/[microwaves]/[infrared]/[visible]/[ultraviolet]/[x-rays]/[gamma rays]
Below are all of the frequencies listed, their danger & capabilities! capabilities & how they are used(if at all) everyday!


GAMMA RAYS
10650-gamma.jpg

First off, Gamma Rays! Gamma Rays, which are located at the very edge of the Electromagnetic Spectrum have the most energy per photons, along with having a very, very small wavelength! Gamma Rays are only produced by very powerful forces, most commonly from stars in the universe. Since Gamma Rays have very short wavelengths they are capable of going through most materials with ease, these particular wavelength are dangerous to living things since these will pass through living organisms body, leaving behind only massive damage. To stop Gamma Rays multiple layers of cement or lead need to be used!


X-RAYS
10651-xrays.jpg

Next, X-Rays! This particular section of the Electromagnetic Spectrum may seem more familiar with you since this is what is used to take a picture of your bones in hospitals! X-Rays themselves aren't as strong as Gamma Rays but still have the ability to pass through most materials(hence bone pictures). That being said, X-Rays are harmful to humans and exposure to them should be avoided unless protected(why do you think you wear a lead vest? :p)


ULTRAVIOLET
10653-ultraviolet-light-bulb.jpg

Next up, Ultraviolet light. This is where the fun starts! Ultraviolet light, although invisible most of the time can be seen if it is located close enough to the visible light part of the spectrum(380nm+). Ultraviolet light has the ability to fluoresence white materials, making them essentially glow!!! In the medical field UV light is also used to kill of cancer cells and in tanning salons causes you to get a tan :D While close to the visible spectrum, UV light is still dangerous to humans! Too much of it can cause mutations in your cells, leading to possible cancers or burning of your skin(think sun tans). (Lasers exist in this region of the Electromagnetic Spectrum)


[VISIBLE]
10654-visible.jpg

Finally, light we can see! Over millions of years the human eye has evolved to allow us to see all the colors to help us navigate ourselves! All the colors you see fall into this part of the Electromagnetic Spectrum! Without this, well...life would be pretty boring wouldn't it? Visible Light dosen't have the potential to cause cancer or go through blocks of cement but too much of it can cause eye damage! Visible Light in itself pretty harmless but like previously said, avoid too much of it in your eyes(i.e looking at the sun, or laser light in your eyes)! Got it? (Lasers exist in this region of the Electromagnetic Spectrum)


[INFRARED]
10656-ir.jpg

Leaving the colorful world of visible light we enter Infrared Light. Infrared Light is radiation just after what we can see. Infrared light has many uses, from being used in TV remotes to detecting heat on people. The heat you feel from the sun, or a fire is Infrared radiation! Infrared Light is invisible if one goes too far from the Visible Light Spectrum(780nm+). The real danger of this radiation is the heat. Infrared Light isn't too dangerous to humans just avoid letting it stay on one spot for too long! (Lasers exist in this part of the Electromagnetic Spectrum).


MICROWAVES
10655-microwave.jpg

After Infrared Light are Microwaves! Microwaves don't generate heat. How does my food cook then? When Microwaves hit water it causes the water particles in food to heat up, essentially cooking it. Microwaves are used for well...making your favorite food! :) Microwave radiation is pretty harmless but should be avoided in high doses as getting hit with this would essentially heat you up. Since your body is mostly water, this would cause you to "cook-up" as it attacks your water cells, just like when meat is put in a microwave.


RADIOWAVES
10657-radio.jpg

Last but not least, are Radiowaves with wavelengths which can reach the size of a football field! This part of the Electromagnetic Spectrum has the lowest energy & longest waves, which allows them to travel long distances. Your favorite radio station uses Radiowaves to send music over long distances so you can hear it from miles, even 10's of miles away! So thank Radiowaves next time your favorite song comes on the radio :p (Radiowaves do not pose any harm to humans generally).



DONE! Above was a brief overview of the Electromagnetic Spectrum & it's properties. I hope you enjoyed reading the information and would greatly appreciate any feedback on how easy this was to read!

Keep on lasing & learnin'

-Alex :)
 





gozert

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Very informative. I knew most of it already, but the gamma rays were pretty new to me. Rep added :beer:
 
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Useful information! I would like to add that Terahertz Radiation exists and it is between infrared and microwaves, but it has very limited uses. It has similar properties to that of infrared waves and microwaves. Small detail, might not even be worth adding in the OP :p
 
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Useful information! I would like to add that Terahertz Radiation exists and it is between infrared and microwaves, but it has very limited uses. It has similar properties to that of infrared waves and microwaves. Small detail, might not even be worth adding in the OP :p


I appreciate the kind words, and the information on Terahertz radiation. I'll see about adding them since this is just supposed to give a generalized and easy view on different waves. In more detail there are also: Far-UV/Mid-UV/Near UV etc... :)

-Alex
 
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@Greenlander Hope you dont mind me adding on:)
ELECTROMAGNETIC SPECTRUM
What is the Electromagnetic Spectrum? The Electromagnetic Spectrum is very simple once you get to know it, honestly, it really is! This spectrum lists the range of all possible frequencies of Electromagnetic Radiation, which include: [radiowaves]/[microwaves]/[infrared]/[visible]/[ultraviolet]/[x-rays]/[gamma rays]
Some properties of electromagnetic waves
1. Electromagnetic waves are transverse wave, which oscillates at 90°
2. They transfer energy from one place to another
3. When electromagnetic waves passes through a medium, its speed and wavelength change but frequency does not change
4. They travel through vacuum with the same speed of (3e8)m/s

GAMMA RAYS
10650-gamma.jpg

First off, Gamma Rays! Gamma Rays, which are located at the very edge of the Electromagnetic Spectrum have the most energy per photons, along with having a very, very small wavelength! Gamma Rays are only produced by very powerful forces, most commonly from stars in the universe. Since Gamma Rays have very short wavelengths they are capable of going through most materials with ease, these particular wavelength are dangerous to living things since these will pass through living organisms body, leaving behind only massive damage. To stop Gamma Rays multiple layers of cement or lead need to be used!
Gamma ray has a wavelength of less that (1e-3)nm. Exposure to them can kill living cells. Scientists and Doctors have put this potentially harmful property to good use, by using it to treat cancer.

X-RAYS
10651-xrays.jpg

Next, X-Rays! This particular section of the Electromagnetic Spectrum may seem more familiar with you since this is what is used to take a picture of your bones in hospitals! X-Rays themselves aren't as strong as Gamma Rays but still have the ability to pass through most materials(hence bone pictures). That being said, X-Rays are harmful to humans and exposure to them should be avoided unless protected(why do you think you wear a lead vest? :p)
X-ray has a wavelength of around (1e-2)nm to 10nm. Similar to gamma ray, x-ray also has high frequency (ie. high energy) which can also be used to kill cancer cells.
X-ray also plays a part in security checks (ie. airport security). They are used to screen bags for potential threats efficiently and effectively. X-ray can also be used to check for tiny flaws in heavy metal equipment.

ULTRAVIOLET
10653-ultraviolet-light-bulb.jpg

Next up, Ultraviolet light. This is where the fun starts! Ultraviolet light, although invisible most of the time can be seen if it is located close enough to the visible light part of the spectrum(380nm+). Ultraviolet light has the ability to fluoresence white materials, making them essentially glow!!! In the medical field UV light is also used to kill of cancer cells and in tanning salons causes you to get a tan :D While close to the visible spectrum, UV light is still dangerous to humans! Too much of it can cause mutations in your cells, leading to possible cancers or burning of your skin(think sun tans). (Lasers exist in this region of the Electromagnetic Spectrum)

Ultraviolet have a wavelength of around (1e2)nm to (4e2)nm. They are used in sunbed for artificial tanning (popular in countries with long period of limited sunlight. however, overexposure to them will cause premature aging and skin cancer.

It is also used in lab to sterilize medical and laboratory equipment.

[VISIBLE]
10654-visible.jpg

Finally, light we can see! Over millions of years the human eye has evolved to allow us to see all the colors to help us navigate ourselves! All the colors you see fall into this part of the Electromagnetic Spectrum! Without this, well...life would be pretty boring wouldn't it? Visible Light doesn't have the potential to cause cancer or go through blocks of cement but too much of it can cause eye damage! Visible Light in itself pretty harmless but like previously said, avoid too much of it in your eyes(i.e looking at the sun, or laser light in your eyes)! Got it? (Lasers exist in this region of the Electromagnetic Spectrum)
visible light has a wavelength of around (3.9e2)nm to (7e2) nm. It is also used in medical purpose and telecommunications.

[INFRARED]
10656-ir.jpg

Leaving the colorful world of visible light we enter Infrared Light. Infrared Light is radiation just after what we can see. Infrared light has many uses, from being used in TV remotes to detecting heat on people. The heat you feel from the sun, or a fire is Infrared radiation! Infrared Light is invisible if one goes too far from the Visible Light Spectrum(780nm+). The real danger of this radiation is the heat. Infrared Light isn't too dangerous to humans just avoid letting it stay on one spot for too long! (Lasers exist in this part of the Electromagnetic Spectrum).
Infrared has a wavelength of around (7e2)nm to (1e6)nm. Human body gives out infrared radiation. The amount emitted depends on the body temperature. Many intruder alarms are Passive Infrared Detector. These detectors does not emit out infrared but instead sense them. When a person walk into a room, the increase in infrared radiation will be detected.

MICROWAVES
10655-microwave.jpg

After Infrared Light are Microwaves! Microwaves don't generate heat. How does my food cook then? When Microwaves hit water it causes the water particles in food to heat up, essentially cooking it. Microwaves are used for well...making your favorite food! :) Microwave radiation is pretty harmless but should be avoided in high doses as getting hit with this would essentially heat you up. Since your body is mostly water, this would cause you to "cook-up" as it attacks your water cells, just like when meat is put in a microwave.
Microwaves has a wavelength of around (1e6)nm to (1e9)nm. It is use for communication with satellites because they can penetrate the atmosphere and travel through haze, light rain, snow, clouds and smoke.

RADIOWAVES
10657-radio.jpg

Last but not least, are Radiowaves with wavelengths which can reach the size of a football field! This part of the Electromagnetic Spectrum has the lowest energy & longest waves, which allows them to travel long distances. Your favorite radio station uses Radiowaves to send music over long distances so you can hear it from miles, even 10's of miles away! So thank Radiowaves next time your favorite song comes on the radio :p (Radiowaves do not pose any harm to humans generally).
Radio-wave have a wavelength higher than (1e9)nm to (1e14)nm. They have the longest wavelength in the electromagnetic spectrum. It can travel across obstructions, like buildings, better than those of shorter wavelength.
 




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