Wavelength and Frequency (Simplified) - Video Tutorials & Practice Problems

On a tight schedule?

Get a 10 bullets summary of the topic

Wavelength is the distance from one crest of a wave to another, whereas frequency is the number of waves within a second.

1

concept

Wavelength and Frequency (Simplified) Concept 1

Video duration:

2m

Play a video:

Light energy can travel through space as electromagnetic radiation in the form of either particles or waves. Now in a vacuum of space, light moves at a speed of 3.00 times 10 to the 8m/s. This is known as the speed of light. Now, when it comes to quantum mechanics and talking about frequency and wavelength, there are these dual ideas that light is just a collection of tiny particles moving together. Whereas others say no light moves as a wave, a unified wave through space. Just realize that both of these help to give us a complete picture of what electromagnetic radiation is and how light energy is involved. Now. In terms of the wave part of this idea, the top of the wave is known as the crust and the bottom is called the trough. So here the top of this wave. So here, here and here these are our crests and then the bottom parts here and here. These are our troughs. Now, when we talk about wavelength and frequency, wavelength uses the greek symbol, Lambda, which looks like this wavelength is just the distance from one crust or trough of a wave to the next one. It is expressing units of meters. So we're talking about one crest to another crest or one trough to another trough. The distance between them, that is our wavelength, which is lambda frequency uses the greek symbol of mu, Which kind of looks like a curvy v. It is the number of waves you have per second. So if we look here, We'd say that this is one two, two and then three waves. So there's three waves involved here. Okay, so this is the first one And then we have this one and then we have this one. So this has about three waves involved. Number of ways you get per second, that is your frequency. So the whole thing is our frequency, which is mu. Now when it comes to mu, it is expressed a units of seconds in verse or hurts. Okay, So seconds in verse is the same thing as hurts. So just remember what we're looking at a wave of light energy. We have wavelengths and we have frequency involved.

2

example

Wavelength and Frequency (Simplified) Example 1

Video duration:

51s

Play a video:

so here it says, based on the image is given below which electromagnetic wave has the highest frequency. So remember, frequency is how many ways we can get per second. So if we don't look, we'd say that from this origin point to this origin point represents one wave here, this will be a second wave. So here's one wave, two waves, three waves, four waves, five waves. This one here would be one wave, two waves and then 25 waves. Then finally here would get one to three, four, 567 and eight. You could also eyeball it and see, like for sure, the image three would have the most amount of waves per second and therefore would have the highest frequency.

3

concept

Wavelength and Frequency (Simplified) Concept 2

Video duration:

1m

Play a video:

So remember when looking at light energy in terms of a wave we have wave length and frequency. And with these two terms we have relationships that can be created. We're gonna say at a fixed speed, the frequency of a lightwave is inversely proportional yeah, to wavelength and directly proportional to energy. What does this mean? Well that means that if our frequency is high, that means our wavelength will be small or low because in verse means that they're opposites of each other. Now, directly proportional means that if one is high the other one is high. So if my frequency is high my energies will be high. Conversely, if I say my frequency values are smaller, low. That means my wavelength values are high or large. And because frequency and energy again are directly proportional. If frequencies are low energies would also be low. So just remember this relationship between these three terms, frequency and energy are directly related. They both go up or go down together. They are the opposite or inversely proportional to wavelength.

4

Problem

Problem

Which energy wave would have the highest frequency from the wavelengths provided?

A

Wave A (453 nm)

B

Wave B (707 nm)

C

Wave C (325 nm)

D

Wave D (910 nm)

Do you want more practice?

We have more practice problems on Wavelength and Frequency (Simplified)