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Jasy Rodriguez
11/25/2025
Physics
Electromagnetic Spectrum
88
•
Nov 25, 2025
•
Understanding the Electromagnetic Spectrum
Jasy Rodriguez
@jasyrodriguez_fpij
1 / 3
Understanding the Electromagnetic Spectrum
Electromagnetic waves are electric and magnetic fields that vibrate, creating waves with different amounts of energy. The energy of a photon (bundle of wave energy) is calculated using E = hf, where h is Planck's Constant and f is frequency. Gamma rays have the highest energy photons, while radio waves have the lowest.
All electromagnetic waves share key properties: speed, frequency, and wavelength, related by the equation v = f × λ. In a vacuum, all electromagnetic waves travel at the same speed , but their wavelengths and frequencies differ with an inverse relationship - as wavelength increases, frequency decreases.
Radio waves have the longest wavelengths (1 meter or longer) and lowest energy in the spectrum. They're produced by making electrons vibrate in antennas and are crucial for transmitting sound and images over long distances. You interact with radio waves daily through cell phones, wireless devices, TV signals, and remote controls.
Fun Fact: Radio waves are named after Heinrich Rudolf Hertz, who proved their existence. That's why frequency is measured in Hertz (Hz), representing how many waves pass by per second!
Radio signals can travel in two ways: ground waves that follow Earth's surface and sky waves that bounce off the ionosphere back to Earth. Since Earth's curvature limits direct transmission to about 80 km, repeaters are used to extend signals by receiving and retransmitting them.
Radio Waves and Microwaves
Radio waves transmit information through modulation - changing a carrier wave to carry sound or data. There are two main types: AM (Amplitude Modulation), where the height of waves varies with the sound, and FM (Frequency Modulation), where the frequency changes to match the audio signal. Radio waves range from low frequencies to ultra-high frequencies (up to 100,000 MHz).
Satellites orbiting Earth use radio waves for various purposes: communication (Comsat), weather tracking (Metsat), navigation (Navsat), scientific research, and Earth resource monitoring (Landsat). These applications have revolutionized how we communicate, navigate, and understand our planet.
Microwaves have shorter wavelengths than radio waves and serve multiple important functions. They power satellite communications by penetrating Earth's atmosphere, enable radar systems to detect objects by reflecting signals, and connect cell phone towers in terrestrial communications networks. Your microwave oven works because food absorbs certain microwave frequencies, converting them to heat.
Did You Know? Communication satellites orbit about 35,000 km above Earth's equator at speeds of 11,300 km/h, constantly receiving and transmitting microwave signals to keep us connected!
Infrared radiation sits between microwaves and visible light on the spectrum. Though invisible to our eyes, we can detect it as heat. All objects emit infrared radiation - cooler objects emit blue-green wavelengths, while warmer objects emit red-yellow wavelengths. This principle enables night vision goggles, remote controls, medical scanning, and specialized photography.
Visible Light and Beyond
Visible light is the only part of the electromagnetic spectrum our eyes can detect. It spans wavelengths from about 4×10^-7 m to 7×10^-7 m and includes all the colors of the rainbow (ROY G BIV: red, orange, yellow, green, blue, indigo, and violet). When combined, these colors form white light, which is why a prism can split white light into its component colors.
Ultraviolet (UV) radiation carries more energy than visible light but has shorter wavelengths. While too much UV exposure can damage skin, moderate amounts help our bodies produce vitamin D. UV light has practical applications too - banks use UV lamps to verify signatures and detect counterfeit money by revealing hidden security features.
X-rays pack even more energy with shorter wavelengths than UV radiation. They're produced when fast-moving electrons hit a metal target in an X-ray tube. X-rays revolutionized medicine by allowing doctors to see inside the body without surgery. Long-wavelength X-rays can pass through flesh but not bones, making them perfect for diagnosing fractures, while shorter wavelengths can penetrate metals to inspect industrial welds.
Safety Note: While X-rays and gamma rays have incredible applications, they can damage living cells, which is why technicians leave the room during X-rays and why gamma radiation is used to kill cancer cells.
At the highest-energy end of the spectrum are gamma rays, which have the shortest wavelengths and are emitted by stars and radioactive substances. They're so powerful they can penetrate most materials, requiring thick concrete or lead for shielding. Despite their danger, gamma rays have valuable applications in cancer treatment through radiotherapy and in sterilizing drinking water and medical equipment.
We thought you’d never ask...
What is the Knowunity AI companion?
Our AI companion is specifically built for the needs of students. Based on the millions of content pieces we have on the platform we can provide truly meaningful and relevant answers to students. But its not only about answers, the companion is even more about guiding students through their daily learning challenges, with personalised study plans, quizzes or content pieces in the chat and 100% personalisation based on the students skills and developments.
Where can I download the Knowunity app?
You can download the app in the Google Play Store and in the Apple App Store.
Is Knowunity really free of charge?
That's right! Enjoy free access to study content, connect with fellow students, and get instant help – all at your fingertips.
Can't find what you're looking for? Explore other subjects.
Students love us — and so will you.
4.9/5
App Store
4.8/5
Google Play
The app is very easy to use and well designed. I have found everything I was looking for so far and have been able to learn a lot from the presentations! I will definitely use the app for a class assignment! And of course it also helps a lot as an inspiration.
Stefan S
iOS user
This app is really great. There are so many study notes and help [...]. My problem subject is French, for example, and the app has so many options for help. Thanks to this app, I have improved my French. I would recommend it to anyone.
Samantha Klich
Android user
Wow, I am really amazed. I just tried the app because I've seen it advertised many times and was absolutely stunned. This app is THE HELP you want for school and above all, it offers so many things, such as workouts and fact sheets, which have been VERY helpful to me personally.
Anna
iOS user
I think it’s very much worth it and you’ll end up using it a lot once you get the hang of it and even after looking at others notes you can still ask your Artificial intelligence buddy the question and ask to simplify it if you still don’t get it!!! In the end I think it’s worth it 😊👍 ⚠️Also DID I MENTION ITS FREEE YOU DON’T HAVE TO PAY FOR ANYTHING AND STILL GET YOUR GRADES IN PERFECTLY❗️❗️⚠️
Thomas R
iOS user
Knowunity is the BEST app I’ve used in a minute. This is not an ai review or anything this is genuinely coming from a 7th grade student (I know 2011 im young) but dude this app is a 10/10 i have maintained a 3.8 gpa and have plenty of time for gaming. I love it and my mom is just happy I got good grades
Brad T
Android user
Not only did it help me find the answer but it also showed me alternative ways to solve it. I was horrible in math and science but now I have an a in both subjects. Thanks for the help🤍🤍
David K
iOS user
The app's just great! All I have to do is enter the topic in the search bar and I get the response real fast. I don't have to watch 10 YouTube videos to understand something, so I'm saving my time. Highly recommended!
Sudenaz Ocak
Android user
In school I was really bad at maths but thanks to the app, I am doing better now. I am so grateful that you made the app.
Greenlight Bonnie
Android user
I found this app a couple years ago and it has only gotten better since then. I really love it because it can help with written questions and photo questions. Also, it can find study guides that other people have made as well as flashcard sets and practice tests. The free version is also amazing for students who might not be able to afford it. Would 100% recommend
Aubrey
iOS user
Best app if you're in Highschool or Junior high. I have been using this app for 2 school years and it's the best, it's good if you don't have anyone to help you with school work.😋🩷🎀
Marco B
iOS user
THE QUIZES AND FLASHCARDS ARE SO USEFUL AND I LOVE THE SCHOOLGPT. IT ALSO IS LITREALLY LIKE CHATGPT BUT SMARTER!! HELPED ME WITH MY MASCARA PROBLEMS TOO!! AS WELL AS MY REAL SUBJECTS ! DUHHH 😍😁😲🤑💗✨🎀😮
Elisha
iOS user
This app is phenomenal down to the correct info and the various topics you can study! I greatly recommend it for people who struggle with procrastination and those who need homework help. It has been perfectly accurate for world 1 history as far as I’ve seen! Geometry too!
Paul T
iOS user
The app is very easy to use and well designed. I have found everything I was looking for so far and have been able to learn a lot from the presentations! I will definitely use the app for a class assignment! And of course it also helps a lot as an inspiration.
Stefan S
iOS user
This app is really great. There are so many study notes and help [...]. My problem subject is French, for example, and the app has so many options for help. Thanks to this app, I have improved my French. I would recommend it to anyone.
Samantha Klich
Android user
Wow, I am really amazed. I just tried the app because I've seen it advertised many times and was absolutely stunned. This app is THE HELP you want for school and above all, it offers so many things, such as workouts and fact sheets, which have been VERY helpful to me personally.
Anna
iOS user
I think it’s very much worth it and you’ll end up using it a lot once you get the hang of it and even after looking at others notes you can still ask your Artificial intelligence buddy the question and ask to simplify it if you still don’t get it!!! In the end I think it’s worth it 😊👍 ⚠️Also DID I MENTION ITS FREEE YOU DON’T HAVE TO PAY FOR ANYTHING AND STILL GET YOUR GRADES IN PERFECTLY❗️❗️⚠️
Thomas R
iOS user
Knowunity is the BEST app I’ve used in a minute. This is not an ai review or anything this is genuinely coming from a 7th grade student (I know 2011 im young) but dude this app is a 10/10 i have maintained a 3.8 gpa and have plenty of time for gaming. I love it and my mom is just happy I got good grades
Brad T
Android user
Not only did it help me find the answer but it also showed me alternative ways to solve it. I was horrible in math and science but now I have an a in both subjects. Thanks for the help🤍🤍
David K
iOS user
The app's just great! All I have to do is enter the topic in the search bar and I get the response real fast. I don't have to watch 10 YouTube videos to understand something, so I'm saving my time. Highly recommended!
Sudenaz Ocak
Android user
In school I was really bad at maths but thanks to the app, I am doing better now. I am so grateful that you made the app.
Greenlight Bonnie
Android user
I found this app a couple years ago and it has only gotten better since then. I really love it because it can help with written questions and photo questions. Also, it can find study guides that other people have made as well as flashcard sets and practice tests. The free version is also amazing for students who might not be able to afford it. Would 100% recommend
Aubrey
iOS user
Best app if you're in Highschool or Junior high. I have been using this app for 2 school years and it's the best, it's good if you don't have anyone to help you with school work.😋🩷🎀
Marco B
iOS user
THE QUIZES AND FLASHCARDS ARE SO USEFUL AND I LOVE THE SCHOOLGPT. IT ALSO IS LITREALLY LIKE CHATGPT BUT SMARTER!! HELPED ME WITH MY MASCARA PROBLEMS TOO!! AS WELL AS MY REAL SUBJECTS ! DUHHH 😍😁😲🤑💗✨🎀😮
Elisha
iOS user
This app is phenomenal down to the correct info and the various topics you can study! I greatly recommend it for people who struggle with procrastination and those who need homework help. It has been perfectly accurate for world 1 history as far as I’ve seen! Geometry too!
Paul T
iOS user
Understanding the Electromagnetic Spectrum
Jasy Rodriguez
@jasyrodriguez_fpij
The electromagnetic spectrum is a complete continuum of all forms of "light" energy, from radio waves to gamma rays. Each type of electromagnetic radiation has unique properties determined by its wavelength and frequency, with all forms traveling at the same... Show more
Understanding the Electromagnetic Spectrum
Electromagnetic waves are electric and magnetic fields that vibrate, creating waves with different amounts of energy. The energy of a photon (bundle of wave energy) is calculated using E = hf, where h is Planck's Constant and f is frequency. Gamma rays have the highest energy photons, while radio waves have the lowest.
All electromagnetic waves share key properties: speed, frequency, and wavelength, related by the equation v = f × λ. In a vacuum, all electromagnetic waves travel at the same speed , but their wavelengths and frequencies differ with an inverse relationship - as wavelength increases, frequency decreases.
Radio waves have the longest wavelengths (1 meter or longer) and lowest energy in the spectrum. They're produced by making electrons vibrate in antennas and are crucial for transmitting sound and images over long distances. You interact with radio waves daily through cell phones, wireless devices, TV signals, and remote controls.
Fun Fact: Radio waves are named after Heinrich Rudolf Hertz, who proved their existence. That's why frequency is measured in Hertz (Hz), representing how many waves pass by per second!
Radio signals can travel in two ways: ground waves that follow Earth's surface and sky waves that bounce off the ionosphere back to Earth. Since Earth's curvature limits direct transmission to about 80 km, repeaters are used to extend signals by receiving and retransmitting them.
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Improve your grades
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Radio Waves and Microwaves
Radio waves transmit information through modulation - changing a carrier wave to carry sound or data. There are two main types: AM (Amplitude Modulation), where the height of waves varies with the sound, and FM (Frequency Modulation), where the frequency changes to match the audio signal. Radio waves range from low frequencies to ultra-high frequencies (up to 100,000 MHz).
Satellites orbiting Earth use radio waves for various purposes: communication (Comsat), weather tracking (Metsat), navigation (Navsat), scientific research, and Earth resource monitoring (Landsat). These applications have revolutionized how we communicate, navigate, and understand our planet.
Microwaves have shorter wavelengths than radio waves and serve multiple important functions. They power satellite communications by penetrating Earth's atmosphere, enable radar systems to detect objects by reflecting signals, and connect cell phone towers in terrestrial communications networks. Your microwave oven works because food absorbs certain microwave frequencies, converting them to heat.
Did You Know? Communication satellites orbit about 35,000 km above Earth's equator at speeds of 11,300 km/h, constantly receiving and transmitting microwave signals to keep us connected!
Infrared radiation sits between microwaves and visible light on the spectrum. Though invisible to our eyes, we can detect it as heat. All objects emit infrared radiation - cooler objects emit blue-green wavelengths, while warmer objects emit red-yellow wavelengths. This principle enables night vision goggles, remote controls, medical scanning, and specialized photography.
Sign up to see the contentIt's free!
Access to all documents
Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
Visible Light and Beyond
Visible light is the only part of the electromagnetic spectrum our eyes can detect. It spans wavelengths from about 4×10^-7 m to 7×10^-7 m and includes all the colors of the rainbow (ROY G BIV: red, orange, yellow, green, blue, indigo, and violet). When combined, these colors form white light, which is why a prism can split white light into its component colors.
Ultraviolet (UV) radiation carries more energy than visible light but has shorter wavelengths. While too much UV exposure can damage skin, moderate amounts help our bodies produce vitamin D. UV light has practical applications too - banks use UV lamps to verify signatures and detect counterfeit money by revealing hidden security features.
X-rays pack even more energy with shorter wavelengths than UV radiation. They're produced when fast-moving electrons hit a metal target in an X-ray tube. X-rays revolutionized medicine by allowing doctors to see inside the body without surgery. Long-wavelength X-rays can pass through flesh but not bones, making them perfect for diagnosing fractures, while shorter wavelengths can penetrate metals to inspect industrial welds.
Safety Note: While X-rays and gamma rays have incredible applications, they can damage living cells, which is why technicians leave the room during X-rays and why gamma radiation is used to kill cancer cells.
At the highest-energy end of the spectrum are gamma rays, which have the shortest wavelengths and are emitted by stars and radioactive substances. They're so powerful they can penetrate most materials, requiring thick concrete or lead for shielding. Despite their danger, gamma rays have valuable applications in cancer treatment through radiotherapy and in sterilizing drinking water and medical equipment.
We thought you’d never ask...
What is the Knowunity AI companion?
Our AI companion is specifically built for the needs of students. Based on the millions of content pieces we have on the platform we can provide truly meaningful and relevant answers to students. But its not only about answers, the companion is even more about guiding students through their daily learning challenges, with personalised study plans, quizzes or content pieces in the chat and 100% personalisation based on the students skills and developments.
Where can I download the Knowunity app?
You can download the app in the Google Play Store and in the Apple App Store.
Is Knowunity really free of charge?
That's right! Enjoy free access to study content, connect with fellow students, and get instant help – all at your fingertips.
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4.9/5
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4.8/5
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The app is very easy to use and well designed. I have found everything I was looking for so far and have been able to learn a lot from the presentations! I will definitely use the app for a class assignment! And of course it also helps a lot as an inspiration.
Stefan S
iOS user
This app is really great. There are so many study notes and help [...]. My problem subject is French, for example, and the app has so many options for help. Thanks to this app, I have improved my French. I would recommend it to anyone.
Samantha Klich
Android user
Wow, I am really amazed. I just tried the app because I've seen it advertised many times and was absolutely stunned. This app is THE HELP you want for school and above all, it offers so many things, such as workouts and fact sheets, which have been VERY helpful to me personally.
Anna
iOS user
I think it’s very much worth it and you’ll end up using it a lot once you get the hang of it and even after looking at others notes you can still ask your Artificial intelligence buddy the question and ask to simplify it if you still don’t get it!!! In the end I think it’s worth it 😊👍 ⚠️Also DID I MENTION ITS FREEE YOU DON’T HAVE TO PAY FOR ANYTHING AND STILL GET YOUR GRADES IN PERFECTLY❗️❗️⚠️
Thomas R
iOS user
Knowunity is the BEST app I’ve used in a minute. This is not an ai review or anything this is genuinely coming from a 7th grade student (I know 2011 im young) but dude this app is a 10/10 i have maintained a 3.8 gpa and have plenty of time for gaming. I love it and my mom is just happy I got good grades
Brad T
Android user
Not only did it help me find the answer but it also showed me alternative ways to solve it. I was horrible in math and science but now I have an a in both subjects. Thanks for the help🤍🤍
David K
iOS user
The app's just great! All I have to do is enter the topic in the search bar and I get the response real fast. I don't have to watch 10 YouTube videos to understand something, so I'm saving my time. Highly recommended!
Sudenaz Ocak
Android user
In school I was really bad at maths but thanks to the app, I am doing better now. I am so grateful that you made the app.
Greenlight Bonnie
Android user
I found this app a couple years ago and it has only gotten better since then. I really love it because it can help with written questions and photo questions. Also, it can find study guides that other people have made as well as flashcard sets and practice tests. The free version is also amazing for students who might not be able to afford it. Would 100% recommend
Aubrey
iOS user
Best app if you're in Highschool or Junior high. I have been using this app for 2 school years and it's the best, it's good if you don't have anyone to help you with school work.😋🩷🎀
Marco B
iOS user
THE QUIZES AND FLASHCARDS ARE SO USEFUL AND I LOVE THE SCHOOLGPT. IT ALSO IS LITREALLY LIKE CHATGPT BUT SMARTER!! HELPED ME WITH MY MASCARA PROBLEMS TOO!! AS WELL AS MY REAL SUBJECTS ! DUHHH 😍😁😲🤑💗✨🎀😮
Elisha
iOS user
This app is phenomenal down to the correct info and the various topics you can study! I greatly recommend it for people who struggle with procrastination and those who need homework help. It has been perfectly accurate for world 1 history as far as I’ve seen! Geometry too!
Paul T
iOS user
The app is very easy to use and well designed. I have found everything I was looking for so far and have been able to learn a lot from the presentations! I will definitely use the app for a class assignment! And of course it also helps a lot as an inspiration.
Stefan S
iOS user
This app is really great. There are so many study notes and help [...]. My problem subject is French, for example, and the app has so many options for help. Thanks to this app, I have improved my French. I would recommend it to anyone.
Samantha Klich
Android user
Wow, I am really amazed. I just tried the app because I've seen it advertised many times and was absolutely stunned. This app is THE HELP you want for school and above all, it offers so many things, such as workouts and fact sheets, which have been VERY helpful to me personally.
Anna
iOS user
I think it’s very much worth it and you’ll end up using it a lot once you get the hang of it and even after looking at others notes you can still ask your Artificial intelligence buddy the question and ask to simplify it if you still don’t get it!!! In the end I think it’s worth it 😊👍 ⚠️Also DID I MENTION ITS FREEE YOU DON’T HAVE TO PAY FOR ANYTHING AND STILL GET YOUR GRADES IN PERFECTLY❗️❗️⚠️
Thomas R
iOS user
Knowunity is the BEST app I’ve used in a minute. This is not an ai review or anything this is genuinely coming from a 7th grade student (I know 2011 im young) but dude this app is a 10/10 i have maintained a 3.8 gpa and have plenty of time for gaming. I love it and my mom is just happy I got good grades
Brad T
Android user
Not only did it help me find the answer but it also showed me alternative ways to solve it. I was horrible in math and science but now I have an a in both subjects. Thanks for the help🤍🤍
David K
iOS user
The app's just great! All I have to do is enter the topic in the search bar and I get the response real fast. I don't have to watch 10 YouTube videos to understand something, so I'm saving my time. Highly recommended!
Sudenaz Ocak
Android user
In school I was really bad at maths but thanks to the app, I am doing better now. I am so grateful that you made the app.
Greenlight Bonnie
Android user
I found this app a couple years ago and it has only gotten better since then. I really love it because it can help with written questions and photo questions. Also, it can find study guides that other people have made as well as flashcard sets and practice tests. The free version is also amazing for students who might not be able to afford it. Would 100% recommend
Aubrey
iOS user
Best app if you're in Highschool or Junior high. I have been using this app for 2 school years and it's the best, it's good if you don't have anyone to help you with school work.😋🩷🎀
Marco B
iOS user
THE QUIZES AND FLASHCARDS ARE SO USEFUL AND I LOVE THE SCHOOLGPT. IT ALSO IS LITREALLY LIKE CHATGPT BUT SMARTER!! HELPED ME WITH MY MASCARA PROBLEMS TOO!! AS WELL AS MY REAL SUBJECTS ! DUHHH 😍😁😲🤑💗✨🎀😮
Elisha
iOS user
This app is phenomenal down to the correct info and the various topics you can study! I greatly recommend it for people who struggle with procrastination and those who need homework help. It has been perfectly accurate for world 1 history as far as I’ve seen! Geometry too!
Paul T
iOS user