Frequency, Wavelength, and the Speed of Light

This video describes what frequency is, how it is measured, how frequency and wavelength are related visually and mathematically, and derives the mathematical relationship between frequency, wavelength, and the speed of light
-More on Light | Wikipedia-
"Light is electromagnetic radiation within a certain portion of the electromagnetic spectrum. The word usually refers to visible light, which is visible to the human eye and is responsible for the sense of sight.[1] Visible light is usually defined as having wavelengths in the range of 400-700 nanometres (nm), or 4.00 × 10−7 to 7.00 × 10−7 m, between the infrared (with longer wavelengths) and the ultraviolet (with shorter wavelengths).[2][3] This wavelength means a frequency range of roughly 430-750 terahertz (THz).
The main source of light on Earth is the Sun. Sunlight provides the energy that green plants use to create sugars mostly in the form of starches, which release energy into the living things that digest them. This process of photosynthesis provides virtually all the energy used by living things. Historically, another important source of light for humans has been fire, from ancient campfires to modern kerosene lamps. With the development of electric lights and power systems, electric lighting has effectively replaced firelight. Some species of animals generate their own light, a process called bioluminescence. For example, fireflies use light to locate mates, and vampire squids use it to hide themselves from prey.
The primary properties of visible light are intensity, propagation direction, frequency or wavelength spectrum, and polarization, while its speed in a vacuum, 299,792,458 metres per second, is one of the fundamental constants of nature. Visible light, as with all types of electromagnetic radiation (EMR), is experimentally found to always move at this speed in a vacuum.[citation needed]
In physics, the term light sometimes refers to electromagnetic radiation of any wavelength, whether visible or not.[4][5] In this sense, gamma rays, X-rays, microwaves and radio waves are also light. Like all types of light, visible light is emitted and absorbed in tiny "packets" called photons and exhibits properties of both waves and particles. This property is referred to as the wave-particle duality. The study of light, known as optics, is an important research area in modern physics."
Wikipedia contributors. "Light." Wikipedia, The Free Encyclopedia. Wikipedia, The Free Encyclopedia, 5 Jun. 2016. Web. 18 Jun. 2016.

[@PrachiPurva]

Being a chemistry teacher ,m just amazed after watching this. This is just superb.

[@CrashChemistryAcademy]

Thanks so much. Comments from educators are always the most gratifying!

[@upaste]

an excellent and clear explanation with good graphics and slow speaking. 10/10

[@wendyplotkin8925]

I have been searching for over 50 years for an explanation of simple wave characteristics that would open up the rest of physics to me. This presentation has achieved that. I am so, so grateful for this experience and can barely restrain my excitement in hoping that the other videos will do the same. Fine teaching is among the greatest gifts one human being can give another!

[@CrashChemistryAcademy]

Thanks, I'm very glad it was helpful! However I should warn you that the model in this video is a simple mathematical wave function, which, while light conforms to mathematically, is missing a few details, an important one being that the wave oscillations quickly diminish from the center down to zero. If you picture a group of waves representing a single photon, say 9 waves, it would have a maximum amplitude at the center, and the amplitude quickly diminishes to zero with the 4 waves on either side of the maximum, all of which are in a 2-dimensional plane in line with the direction of travel. This explanation is not really necessary to understand light-as-wave function, but just wanted to let you know it has been simplified, and there are more sophisticated models out there.

[@joeljosh3877]

Sir, by your teaching I was able to understand the concept of "Frequency, Wavelength, and the Speed of Light".You are helping a lot of students with your video. Keep making such amazing videos.😇

[@johnberry5339]

Very interesting thank you, I just need to watch it another 10 times to sink in... :)

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I'm the same way

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You're doing such a great work for students. Thank you for making the video.

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I'm Malaysian Citizen.. Proud with u to share the superb knowledge

[@CrashChemistryAcademy]

Thank you! Hello to Malaysia!

[@raiskassimibrahim616]

This is the best video ever period. I wish everything science can be simplified like this !

[@8polyglot]

Thank you, so helpful. Needed a clear explanation of wavelength, frequency, and speed of light in order to study for ham radio exam and this helped.

[@CrashChemistryAcademy]

I love that! You are so welcome! Good luck!

[@juanfelipe8484]

This is one of the best explanations I’ve ever watched

[@vijayagurudas7374]

Fantabulous video and the best digramatic explanation of the concept. As a student at present I am very fortunate to have seen this . Thank you so much Sir😊👏🏿

[@nicolewhitman5068]

Dude! You just saved me! AMAZING LESSON! THANK YOU

[@calvinf9218]

Nice video. I have a test tomorrow and part of it is on energy of radiation, and this made it so much clearer for me. Thanks, mate!

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Explanation is too good...made me understand the thing in no time..thx

[@krishnanshudey3831]

Thanks you for clearing all my doubles. Really all solutions in one video.

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thank you. great explanation

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Loved this video.Nice representation!👍

[@hussein2002yes]

This is perfect. Simple and straight to the point.

[@shivanisamal205]

The best explanation I ever got!!! 💜💜💜 Thank u for clearing all my doubts sir!!!!

[@CrashChemistryAcademy]

You're welcome!

[@ashleybroussard9039]

Beautiful!!!! Thanks so much for posting. Very clear.

[@karinamatos4253]

Incredibly well explained. Thanks.

[@sonalisatirkey2174]

You are saving my life thank you so much, I wish my teacher taught like this

[@tymothylim6550]

Thank you very much for this video! It was really clear and I really enjoyed the animation showing the moving of waves across a fixed point!

[@jeremiahderosier9854]

Thankyou I'm thankful for what you teached me.

[@JohnRaschedian]

That was one perfect explanation. Thank you sir!

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Most excellent video it helped me immensely in my grasp of things in life and nature WOW i can apply this to the world around me thank you so much and also i subsribed to you so god bless

[@anshulprakash5370]

Best explanation ever

[@ASMRChemistry]

I am going to refer this video to my students to visualize frequency etc.! Thank you!

[@CrashChemistryAcademy]

Thanks! Always nice to hear from educators.

[@shivikadubey]

Beautiful explanation + appropriate graphic = complete knowledge ❤

[@AkashdeepSingh-mz1lk]

Thanks sir Excellent explanation Love from india ❤️

[@CrashChemistryAcademy]

Love to India! 💖

[@Animerulespeople]

I get it but I don't TRULY understand it fully. Which is why I'll have to watch this a few more times...

[@anandsuralkar2947]

3:56 i am blind now

[@rachitgupta6109]

Thanks you sir. It helped me a lot getting my concept cleared of frequency, Wavelength and relation with speed of light

[@josuesolisramirez6984]

What a beautifull explanation of this natural phenomenom, still havig a hard time with my light meter and its operating range

[@staceyshpaner1904]

I am forever grateful to you sir! At this exact moment, at 5:57 in the video, I FINALLY understood what is going on in my chemistry class. Wavelength is METERS Frequency is PER SECOND Speed is METERS PER SECOND

[@CrashChemistryAcademy]

I'm glad it helped! often students get confused by symbols versus units-- always keep your units in mind

[@manjaridebnath2293]

cleared the full confusion. Fantastic explanation and also animation..... Thanks a lot

[@YaseinAbdi]

well explained with good graphics illustrations

[@rehanmomin2082]

very amazing video for a physics lecture

[@robertomercado7265]

This was great I knew about frequencies from music and trig but didn't know about the relationship of wavelength and frequency with light speed. Cool.

[@letsplayee]

The animation and explanation is really amazing. Thanks for the amazing video.

[@CrashChemistryAcademy]

You're welcome!

[@srinivasjadi3945]

Good explanation and clarity

[@catube6915]

One of the best explanations.

[@rehanmomin2082]

you have defined very well sir thanks a lot

[@tejdeepteja5089]

WHAT AN EXPLANATION SIR ! THANKS A LOT

[@praveensaw2937]

Bahut aacha video So interesting

[@sanjaykadale3863]

Excellent Explaination

[@user-ru7im4kz2g]

why it looks crazy when I look at that harmonic waves in the video, its blinking into my eyes

[@ayaaltamimie8911]

you deserve the world I've been trying to fit this in my head and I couldn't my brain wasn't braining and u brained it, I love youuuuuu.

[@CrashChemistryAcademy]

Thanks for the comment. Luv u 2!

[@shashwatvaishnav4458]

this is amazing!! i hv watched more than 10 videos on relation between wavelength, frequency and speed of light but this video is the most satisfactory perfect explanation sir thank u so much💗💗

[@CrashChemistryAcademy]

❤️

[@missionindianforeignservic5476]

Sir I am from India yor vedio helped w a lot to understand this topic, thank u very much sir

[@CrashChemistryAcademy]

love to India💖

[@vista419]

Thanks so much!! This cleared so much up

[@atharvadolhare8263]

Great Explanation

[@mrrkaushal3115]

wow amazing its help me a lot..thank you sir...im from india.

[@dhruvvarma2877]

Really amazing and a helpful video. Hope for new videos to be uploaded. With regards, Yours affectionately.

[@CrashChemistryAcademy]

Thanks! Heavy teaching load... slow going with making vids.

[@Ilyl783]

Thank you! This was very helpful

[@johnknoxville4304]

i loved it. our chem teacher included you video for a better understanding

[@CrashChemistryAcademy]

That's great! Thanks for telling me.

[@bengrizzlyadams6187]

I have a question, when light travels through water, does it keep the the same speed, I know refraction has an impact on wavelength, does it mean it will accelerate the frequency to keep speed a constant?

[@mykhailoshpakov6487]

Ben Grizzly Adams , I think speed of light depends on environment. The professor described speed of light in vacuum , but in water it gonna have lower speed I guess

[@bengrizzlyadams6187]

@@mykhailoshpakov6487 Well, it will have to depend on environment as it seems to reacquire energy when changing means, and it would not make any sense if there is a finite quantum of energy in each photon. (Also how would it travel for billions and billions of light years??) So you have to look into where it acquires that energy from. Is there some form of underlying substrate that gets inducted as opposed to self standing particles? I'd be more incline to think that.

[@konatadesuka]

Excellent explanation. I just couldn't get around the explanation of why a 2400MHz signal had a wavelength of about 12cm. It didn't make sense for me as it's a very high frequency, why "a piece of that wave would be 12cm", same with "short wave" or "30 meter wave". It all came together when the speed of light got involved, so that electromagnetic wave travels really really fast through space. Now it's sensible to think that I can stop time and see that "12 CM" EM wave but as soon as time starts moving again, it propagates really fast and "goes away".

[@CrashChemistryAcademy]

Thanks! It's great to be able to understand the world around you!

[@Noobgamer-xc2jl]

This is helpful education for all . Thanks

[@IanRamon]

thank you very much !! very very clear! visual, slow talk, perfect

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[@andrewferg8737]

Clear and thoughtful explanation. Thanks.

[@fasih333]

Sir superb conceptual lecture you have given, thanks a lot for making such video. Keep making and keep clearing concepts❤❤❤❤

[@CrashChemistryAcademy]

Thanks!

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You are great personality of world astronomy Good presentation 👏

[@BTMECPRUDHVIDHANUSH]

Thanks sir best video for understanding

[@ashish123as]

Excellent sir

[@muhammadbilalhameed9333]

Thanks sir

[@myagrimm4719]

Thank you for such clear explanations!

[@CrashChemistryAcademy]

I’m glad it was helpful!

[@recreationalchannels8693]

Sir, Your videos are outstanding. I watch your videos regularly. Many doubts on Physics were cleared through your channel. Sir it is a request, would you kindly make a video on how Max Planck really derived the value of his universal constant. There are many videos available but nobody reached that point what I am searching for. His actual experiment and his method to derive the constant. Thanks

[@CrashChemistryAcademy]

I like your suggestion, and I may make a video on this, but there was no experiment that Planck did. Planck "discovered" the constant as a way to fix a mathematical flaw in the expression of energy in black body radiation. The math of black body radiation of that time (1900) showed that it would reach infinite energy in the ultraviolet range, which of course was not possible, and Planck found the number that when inserted into the math fixed the problem, which became Planck's constant. It was five years afterward, in 1905, that Einstein showed Planck's constant to represent something real through his experiment about the photoelectric effect, for which he won the Nobel Prize. Planck himself was skeptical that the constant represented any physical reality until Einstein's experiment. That also prompted the Nobel committee to give Planck a Nobel prize, in 1918, three years before Einstein received it.

[@chris_0266]

Why is it that al Chemistry videos have such a bad audio??? Apart from that, I found this very helpful!!

[@CrashChemistryAcademy]

It little known, but the majority (89.6%) of chemists are deficient in their understanding of electronics.

[@chris_0266]

@@CrashChemistryAcademy Yet all chemists must be pretty smart. Here we are learning from their videos HAHA thanks for the useful video again!

[@CrashChemistryAcademy]

😊 I'm glad you liked it!

[@melvinmazariegos6065]

Great Video!

[@PizzeyTechnology]

Great video, very clear explanation and graphics. Thanks.

[@mochax]

Thanks great explanation

[@OrenLikes]

1:01 "A wave cycle is a single up-down motion" shown: down-up motion... In other places, waves shown to start downward. Sure, they oscillate, but "traditionally" they shown starting upward.

[@asdfghjkl-fn5no]

this was amazing, thank you

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istg i love this tysm, may god bless you.

[@Nik-by5mi]

Can you do a video explaining "Why Light slows down when traveling through Glass!" But it can then "re-speed up" when it exits the glass? how does this happen and why? Also: Does the speed of light stay constant when traveling through the glass medium? Meaning does it keep getting slower and slower through thicker glass or does it stay at a constant slower light speed. (assuming the glass is equal temper all around) Thanks Nik

[@CrashChemistryAcademy]

Great questions! I wish I knew more about this. I have looked for answers to these questions for a few years and have found that there does not seem to be concrete agreement among physicists about the mechanism for light slowing in a non-vacuum. Also, I do not think your question of the constancy of the speed is really answerable since the speed of light going through a transparent medium like glass is measured from the point of entry to the point of exiting. I imagine someone has tried to measure light speed within the medium, but I have not seen anything about it. Food for thought!

[@Nik-by5mi]

@@CrashChemistryAcademy Yes, I too am having trouble finding these answers as well.. It would seem like these answers should be common place. Odd they are not. - Aether force -

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You got my subscription!

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Thanks sir you have made concept very very easy

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Thanks alot

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Thnx for sharing 👍

[@INFOGUIDEBENGALI]

Lucid explanation. Thank you very much.

[@sohailjanjua123]

Hi, I like your lecture. Thanks

[@ericpham5198]

I think light speed depending on two separate frequency because light need two crossing frequencies one with emf and the other of gravitational or electric field therefore each color has different speed

[@ASHUTOSHKUMAR-cq7rk]

I'm not know properly english but your diagram is helpful .

[@amirbazgir2106]

Great video

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Thank you for explanation

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Thank you so much. This helped a ton

[@CrashChemistryAcademy]

Yay!

[@anilkumsrtripathi9772]

Thank you sir for explaining. If this thing taught in my school literally physics will become interesting for me

[@CrashChemistryAcademy]

😊

[@brookzera218]

Wait why am I understanding this ! Lol u r the best teacher !!!

[@shehzadsingerstudios6948]

Wow great info...nd lght is so fast amazing

[@rafidismail3505]

Thank you!!!!!!!!!! It was super super helpful and I got a test tomorrow

[@SoapBoxingInTheDark]

Thanks Dr.W

[@CrashChemistryAcademy]

Thanks Spencer, always a pleasure! 👍

[@malasharma2723]

Thank you sir...... It clear all my doubts......... Thanks a lot........ 😃

[@annanelson9422]

very helpful thank you so much!!

[@MrTimothytim]

Do you have a exact spectrum chart of radio frequencies in harmonic over tone resonance?

[@rigveda5105]

Very good explanation!