Electromagnetic Spectrum (Simplified) - Video Tutorials & Practice Problems
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The Electromagnetic Spectrum is the different forms of radioactive energy that exists in our universe.
What is the Electromagnetic Spectrum?
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concept
Electromagnetic Spectrum (Simplified) Concept 1
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Hey everyone. So in this video we're gonna talk about the electromagnetic spectrum. Now, the electromagnetic spectrum itself is just a continuum of electromagnetic radiation that contains all wavelengths and frequencies Now electromagnetic radiation, this is just the flow of light energy that itself is traveling at the speed of light through space as either an electric or magnetic field. Now it was the physicist max Planck and Albert Einstein that theorized this radiation was made of packets or particles. Now this light particle or packet was referred to as a photon and a group of them was called a quantum. Now, as we move through the electromagnetic spectrum as we go from left to right, we're gonna be going from the radio waves all the way to gamma rays. So we need to realize here is that moving in this direction has a profound effect on our wavelength or frequency and also energy. So as we're moving from left to right towards gamma rays were going to say that our wavelengths will be decreasing and our frequencies will be increasing. Now, remember we talked about this in previous videos that there is a direct relationship between frequency and energy. So here if my frequencies are increasing, that means my energies are also increasing. If we take a look here at the electromagnetic spectrum itself. Up here we have mu which represents hertz which represents our frequency. And we're gonna start out with our long radio waves, they have energies that are around 10 to the zero hertz or one hertz and they can go up further as we move from left to right on the bottom. We have lambda as our symbol, which represents wavelength traditionally in meters. So if we're taking a look here, we can see that our frequency is one hertz and our wavelength is 10 to the 8th m. So you can see wavelength is pretty huge. It's a large number. Frequency is a very small number. And we're gonna start out with our long radio waves to start when we go past the long radio waves, we're gonna go into our radio waves and remember radio waves themselves are broken up into AM and FM. If you're looking at the dial on your car for the radio, you know that you can transition from AM stations to FM stations remember that AM stations typically have smaller numbers. That's because they have smaller frequencies. FM have larger numbers, usually in terms of megahertz and that's why they're higher up. Once we pass radio waves we go into microwave and then after microwave we go into infrared. Now this portion here, that's very colorful. Remember this is the portion of the electromagnetic spectrum that we can see with our own eyes without the use of instruments. This is the visible light region. Okay, so you can see that the visible light region makes up a very small portion of the entire electromagnetic spectrum. After the visible light spectrum we go into UV and after UV we have X rays and then finally gamma rays. Now some books may talk about cosmic rays out in space but we typically don't talk about this within chemistry. So just realize that we're going to go just go to gamma rays now. What can we see here? Well, this wave here represents the relationship of wavelength and frequency. We can see that initially the distance between each wave, it's pretty big. There's a vast distance between them. Remember that distance represents our wavelength. You can see waving starts off pretty high and what happens as we move from left to right. You can see the wavelength is becoming more tightly packed. That's because my wavelength, the distance between crests of the waves is decreasing and the frequency of waves that get per amount of time is increasing. So my frequency is increasing. But you might say jules. There's so many different terms here with the electromagnetic spectrum. How am I supposed to remember all of them? Well, that's when we use our memory too. So our memory tool here says that large rude Martians invented very unusual X ray guns. So if we take a look here at everything we highlighted, we can say large stands for long radio waves, rude stands for radio waves. Martians are microwaves invented is for infrared. Various for our visible light spectrum. This small portion here unusual is for U V X ray is for X rays and then guns here is for gamma rays. So use this memory tool to help you remember the order of the electromagnetic spectrum and remember as we move from long radio waves all the way to gamma rays, we see that our wavelengths are decreasing as our frequency is increasing.
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example
Electromagnetic Spectrum (Simplified) Example 1
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So here we're gonna use our memory tool to help us with this example. Question. It says which kind of electromagnetic radiation contains the greatest amount of energy per Adam here. Remember, as we move from left to right, we're going to say that our frequency increases so mu is increasing and this is important to know because remember, energy and frequency are directly related, so the greatest amount of energy would correlate to the highest frequency. So who's most to the right here if we look, microwave is for Martians. So that's out X rays over here. And the only thing higher than that is gamma rays. And we don't have gamma rays listed as an option. So here are answer would have to be choice. Be Remember. Large, rude Martians invented very unusual X ray guns stands for long radio waves, Radio waves. Here we have microwaves. Here we have infrared, the visible light spectrum. We have UV light X ray and then gamma ray
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concept
Electromagnetic Spectrum (Simplified) Concept 2
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1m
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So the visible light spectrum represents a small portion of the continuum the electromagnetic spectrum itself um that can be seen without the aid of instruments by us. And here we're going to say that in order to remember the colors involved with the visible light spectrum. Just remember Roy G biv here are is red. Then we have orange yellow, we have here green, blue, indigo and violet. Now realize that sometimes in more modern visible light spectrums they'll combine indigo and violet together and just say it's violet. And when we're talking about the visible light spectrum realize that it ranges from 700 nanometers for red light all the way to around 380 nanometers for violet light. And remember in terms of the electromagnetic spectrum we're gonna say that red is near infrared and then the violet end is next to ultra violet. No that's blue, but you get what I mean. So that's a good way of remembering what other electromagnetic radiations are near the visible light spectrum. Red is next to the infrared and then violet is next to ultraviolet. So just remember the visible light spectrum is important to us because that's what we can see with our bare eyes without the use of any types of instruments
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Problem
Problem
Which of the following sources of electromagnetic radiation will have the highest energy?
A
Light A (595 nm)
B
Light B (0.0303 cm)
C
Light C (0.000510 m)
D
Light D (291 μm)
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Problem
Problem
A carbon–oxygen double bond within a sugar molecule absorbs electromagnetic radiation at a frequency of 6.0 x 1012 s-1. What portion of the electromagnetic spectrum does this represent?
A
Radio Waves
B
Micowave
C
Infrared
D
Green Light
E
Gamma Ray
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Problem
Problem
X-Ray detectors are devices that use scintillators to convert X-rays into light in order to detect X-Rays indirectly. Which of the following would be picked up by an X-Ray detector:radiation with a wavelength of 0.85 nm or a frequency of 6.52 x 1011 s-1?
A
radiation with a wavelength of 0.85 nm
B
radiation with a frequency of 6.52 x 1011 s-1
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