I did not expect the glass lens to affect the EM waves like that! That really makes a connection for me that was always missing. The idea that radio, light, and X-rays are the same "stuff" but at different frequencies is now clear in a way it never had been before. My mind is blown.
@shazzz_land2 жыл бұрын
a couple of year ago in some campus dorms in east europe which didn't have internet cable in every dorm but only a wireless point at every floor people would put their wireless receivers near some windows in the hope of getting a better signal. curious now if a decent size glass jar with the opening towards a wireless emitter in which you'd have a wireless receiver would amplify the signal
@WSmith_1984 Жыл бұрын
Here's some more for you. Modern science isn't correct..... All energy and matter in one simple explanation.... here goes... First we have a radio wave all the way to gamma waves which in turn create hydrogen then from there everything is basically a compound of hydrogen and will decay back to hydrogen before turning back to gamma waves..... There are no free moving electrons within matter.... I use this analogy to simplify it in my mind..... imagine a line of people standing a mile long (each person represents a copper atom in a wire) the first person starts a Mexican wave at one end ( the source ) , as the information propagates along the line ( by exciting each atoms magnetic field ) you would see an continuous wave of the peoples arms transferring the charge/information back and forth but the atoms and electrons don't actually move at all..... Think about it, from the source where electricity is "generated" to the ultimate end use, there's various breaks in chain of that electricity, it goes through controllers, transformers, all sort of components.... the transmission happens because of the magnetic field strength of the atoms in the wire being increased and decreased, not because of an actual "electron" flowing anywhere....
@RichardBronosky Жыл бұрын
@@WSmith_1984 I like it!
@ronarant2897 Жыл бұрын
Yes that was very interesting and informative! I was also surprised by that, I wish these types of experiments and demonstration were still done, I think it would help in the understanding or it would have helped me at least.
@claudiozanella256 Жыл бұрын
Indeed I have the same problem, he uses a PERSPEX lens, how can it focus EM waves? Something is wrong.
@quartztoe42852 жыл бұрын
People who were alive during the invention of this technology really teach it better than people nowadays. Nowadays, people just assume you know things and skip past all the fundamentals, but back in the day, they had just learned of this technology and they taught it to newbies the way they learned it.
@saliva77610 ай бұрын
I guess em-Waves werde discovered 100 - 150 years earlier..
@kakandecharlse85485 ай бұрын
South of the Sahara worse. Bad teachers can make people hate a good subject
@jeremycole300824 күн бұрын
Im old enough to remember when paper manuals had a "theory of operation" section, so you could read exactly whats going on, right to the nth degree
@patricksmith44242 жыл бұрын
When you hear a man speaking in that old fashioned more upper class English accent, you listen! I learned so much, and this is how physics should be taught, thanks for posting.
@markwilliamson91993 ай бұрын
Famous of course in Adelaide Father and Son. Proud of our Australian Nobel prize winner. That’s why Adelaide University has the Bragg laboratories. By the way Lawrence was born in Adelaide, Australia so this is the Adelaide accent for someone born late 19th century.
@wphubert6 жыл бұрын
This is a fine demonstration why fundamentals need to taught by great masters and not grad students. A marvelous opportunity to learn !
@bobodeyuca4 жыл бұрын
There are some pretty good grad students tho, when they aren't swamped with their own work
@johnc34032 жыл бұрын
Great learning can be found in many places and it is good advice to grab it with both hands, be critical in your thinking and question everything. Don't be taken in by a pipe, a tweed jacket or some grainy footage, at least, not for sentimental reasons. That's not what we are here for. The laws of electromagnetism have not changed and there are many modern teachers that will take you down the rabbithole of EM theory, just as well as Sir Lawrence did here, ..if maybe a little less dapper in presentation :)
@WSmith_1984 Жыл бұрын
@@johnc3403 here's some for you. Modern science isn't correct. All energy and matter in one simple explanation.... here goes. First we have a radio wave all the way to gamma waves which in turn create hydrogen then from there everything is basically a compound of hydrogen and will decay back to hydrogen before turning back to gamma waves..... There are no free moving electrons within matter.... I use this analogy to simplify it in my mind..... imagine a line of people standing a mile long (each person represents a copper atom in a wire) the first person starts a Mexican wave at one end ( the source ) , as the information propagates along the line ( by exciting each atoms magnetic field ) you would see an continuous wave of the peoples arms transferring the charge/information back and forth but the atoms and electrons don't actually move at all..... Think about it, from the source where electricity is "generated" to the ultimate end use, there's various breaks in chain of that electricity, it goes through controllers, transformers, all sort of components.... the transmission happens because of the magnetic field strength of the atoms in the wire being increased and decreased, not because of an actual "electron" flowing anywhere....
@SplendidKunoichi Жыл бұрын
@@johnc3403 indeed, for some reason people always seem to forget there's a happy medium between great master and grad student called a teacher
@markwilliamson91993 ай бұрын
He was a great teacher at Adelaide University, hence the last called Bragg
@craigdallen2 ай бұрын
Excellent - no graphics, no animations. Just good physical explanation. This really gets the point across..
@divinecreation62 ай бұрын
Lol what's your problem with graphics or animations
@chrisstrobel84906 жыл бұрын
Actually seeing the experimental apparatus used to investigate these phenomena is truly eye opening.
@adurgh5 жыл бұрын
Why isn't science being explained this elegantly anymore nowadays?
@RiArchives5 жыл бұрын
We'd like to think we're still carrying on the legacy of the greats who have come before, from Faraday and Davy to the Braggs and Longsdale. Whether you're interested in long-form or short-form science content, KZbin exclusives or broadcast TV shows, our main channel uploads new content every week - kzbin.info
@bobodeyuca4 жыл бұрын
I'd argue that it is! There are some really really great lectures all over the world. Additionally, we have resources like youtube, and books like Griffiths Introduction to Electrodynamics for free as a pdf on the internet. If people have a bit of calculus and diff eq background (if not khan academy is great) the world is their oyster! You can pretty much learn whatever you want
@adurgh4 жыл бұрын
im quite familiar with most of the resources you’ve mentioned. They are very good, but nothing that comes close to this here, as far as physics teaching goes..
@whiterottenrabbit4 жыл бұрын
Because nowadays, everything is done in a really half-assed don't-give-a-shit manner, including explaining science.
@vk68323 жыл бұрын
Because people scream about it being 'White supremacy'
@РоманОрлов-л3х3 жыл бұрын
It's butefull lesson. Благодарю тех кто выложил. Такие лекции заставляют задумываться над многими процессами .
@alexeyleontev72203 жыл бұрын
Что за излучатель в его опытах не подскажешь?
@alocin1102 жыл бұрын
What Sir Lawrence Bragg demonstrating is well understood: He demonstrated the deference between Education and Learning. Hats off to him in respect.
@nickharrison37486 жыл бұрын
Super..much better than modern animations
@aniksamiurrahman63653 жыл бұрын
Sir Bragg is a legend.
@kundeleczek13 жыл бұрын
It is much easyer to animate than make things in real. Beside, you have full control during creating animation.
@Traderhood2 жыл бұрын
Nonsense.
@Mahfknamsayn3 жыл бұрын
That visualization of a wave with moving parts is amazing
@luisboza43613 жыл бұрын
I KNOW ABOUT EM WAVES EVERSINCE I WAS VERY YOUNG WHEN I USED TO STUDY RADIO AND TV. BUT THIS CLASS DEMONSTRATES THOSE PRINCIPLES SO WELL THAT NOTHING'S LEFT FOR IMAGINATION. YOU ACTUALLY SEE WHAT HAPPENS. WHAT A MASTERPIECE OF PADAGOGY. SCIENCE FLOWS LIKE A RIVER WITH THIS EXPLANATION. GOD BLESS SIR LAWRENCE.
@banibandyopadhyay46985 жыл бұрын
He is my favorite scientist since i was 10 years old now i am almost 18 it has been 8 years aprox and i been loving physics since...physics is my first love...
@unlikelyprophet32605 жыл бұрын
The earth os flat covered by molten glass dome saline sea moving around magnetic mountain at north generates charge which is conducted through this firmament simultaneously powering stars and running sun positive hot and moon negative cold lights around mixing air into noble gas filled upper atmosphere now you know what tesla knew and you can understand our fathers creation
@wheelie635 жыл бұрын
thats cool........wb
@zapthathattrick6 жыл бұрын
I wish to goodness high school and colleges taught concepts like this before beginning the math
@abdullaalmosalami5 жыл бұрын
The math is what gives you proper respect for the physics, and also shows you even more on how beautiful the phenomenon you are observing is.
@eumesm97705 жыл бұрын
It's like he said. 02:49 what he is teaching it's just 'the nature of this'
@davidmiller49424 жыл бұрын
I agree showing concrete before the abstract is very important. Show visually first and then the math to explain it. Then, the Math becomes much more interesting.
@kimmarlow3094 жыл бұрын
It's interesting that he pointed out it was Faraday that made the discovery, who could not do the math. Maxwell who could do advanced math was able to refine Faraday's work into exact math equations. Quantum super semetry is basically described as best guess for X1 and X2 and 3and4. In particular physics they use the P word to signify best guess on what you know. When they hunted the Higgs particle they thought it should appear within an estimated energy range. There again best guess. You can sum it up as the field of discovery isn't going to be the work of elegant equations, but after the discovery then the math can make the discovery universally understandable, and defined. In Physics Fineman had all kinds of squiggly lines and arrows he used instead of math, because they represented what he thought, but couldn't prove.
@woodytedttrailhunter76064 жыл бұрын
bzzzt, wrong.
@MirlitronOne Жыл бұрын
TWO great science educators at work; Lawrence Bragg AND Bill Coates, long-term senior demonstrator at the Royal Institution. I am glad to have had the privilege to meet the latter, a personal hero.
@jeremiahmullikin8 ай бұрын
I'm fortunate to have viewed this presentation.
@muhammadaltaf96515 жыл бұрын
Thank you Sir for such a great lecture and your contribution in science education.
@0011-b2s5 жыл бұрын
One of the most amazing things on this video is the use of a Glass lens to capture and focus a radio wave into the antenna. That was amazing ! I seen it and said No Way!😮 But simple physics works !🤔 I will have to try this! I want to build a super antenna. I heard that using Mercury in a tube connected to your antenna it works great.
@Gabeyre4 жыл бұрын
When measuring the Wavelength, the professor clearly said that based on the lengths measured, the waves were short in length and were similar to light waves not radio which have longer wave lengths. Or perhaps he changed the wave generating apparatus after using the lens and before measuring the wavelengths..
@K.D.Fischer_HEPHY3 жыл бұрын
Btw... this Klystron was rocking a solid 30GHz ! Stunning to think about that this has been allready done in the 50's.
@AndrewKamenMusic5 жыл бұрын
The way this is filmed is incredibly therapeutic lol
@hablemossobreciencia12433 жыл бұрын
Genial! Una de las explicaciones más claras de las bases del electromagnetismo que he visto. Realmente excelente!
@sau0026 жыл бұрын
This video should formally become a part of school curriculum
@locknut53822 ай бұрын
It would be interesting to see a precise date for this recording. As far as I can tell, it must have been somewhere between about 1962 the year after the first proposal of these audience-free recordings, and 1971, the year of his death. Maybe around 1965?
@jamesmhango26194 жыл бұрын
Finally feels confident of what i thought i knew.
@johnlbales27736 жыл бұрын
Outstanding! Wish I'd seen these demonstrations in 1968!
@BiancaAguglia3 жыл бұрын
I wonder if any of the people from 1968 wished they could see these demonstrations in 2021. 😁 I know what you meant though. It would have been amazing to attend one of Sir Lawrence Bragg's presentations.
@Fomites2 жыл бұрын
Was it 1968? I was wondering. If so, how did you find out?
@malcolmbeale49702 жыл бұрын
Thank you, an incredible illustration of electromagnetism and wave propagation. The video is a gem.
@ProDroneControl3 жыл бұрын
Amazing!! With zero mathematics, a rare gem video making us watch the actual behaviour of invisible. Grear professor.
@allanwrobel66075 ай бұрын
Never seen various phenomenon of light shown so clearly. We have a shed load of CGI now but none do the subject justice in the way this presentation does. I wish I had known about this when my son was being taught physics as school.
@birgermuller36876 жыл бұрын
Very informative and easy to grasp. This British gentleman is a good teacher indeed.
@aronhighgrove4100 Жыл бұрын
@ianl707 This ageism is annoying and *not* a good indicator if someone is smart, a good teacher or not.
@ronaldhenry4057 Жыл бұрын
Fantastic presentation on EM energy and waves. Thanks.
@carmelpule69546 жыл бұрын
This is an interesting video indeed. I would have liked to have heard Sir Lawrence Bragg mentioning the fact that electromagnetic waves are to be looked upon as any other formation of ELECTRIC LOOPS and MAGNETIC LOOPS linking each other. For any machine to work, an ELECTRIC loop MUST link at right angle with a MAGNETIC loop.This relation must also exist for DC conditions. In AC conditions, the loops are oscillating but they are still LOOPS, just like two wedding rings, linked, CURLING each other at right angle. These loops were clearly "seen" when he used the transformers working at 50 Hz. The electromagnetic wave in the waveguide and the horn he used, were also loops of magnetic fields linking loops of electric fields. and while in the waveguide the loops of magnetic fields were always in the waveguide space, while the electric loops flowed along the walls of the waveguide and crossed the rectangular waveguide across its flatter face. These loops called the E/M loops kept on creating each other as they left the waveguide horn. What was shown as LOOPS in the transformer, remained as loops in the air between the transmitter and receiver antenna . I wish he said that. When he showed the induction coil experiment he said "When I move the magnet INTO the coil..............." Well of course, he did say that he moved the magnet INTO the coil, but the magnetic lines parallel to the motion did not generate the voltage in the coil by the magnetic lines moving INTO the coil parallel with the motion as what happens is, that more magnetic lines crossed RADIALLY to fill the centre, to cause a rate of change of magnetic flux, which crossed the coil at right angles in a radial manner. I would have been careful when using the word INTO the coil at 2:30, as that suggests that the magnetic line moved parallel with the central axis of the coil and that sort of movement does not generate a rate of change of magnetic flux. The magnetic lines parallel with the movement, "moved radially" to cause the rate of change of magnetic flux linking the coil. If he used a rotating generator that is how the magnetic flux would have moved into the coil, sideways. In fact the rate of change of magnetic flux is clearly shown by the meter as when the magnet was stationary inside the coil, the meter returned to zero . When he withdrew the magnet from the coil the magnetic flux crossed out in a radial manner giving the deflection in the other direction. The magnetic field around the end of the magnet he used is rather complex I wonder how many viewers deciphered " INTO" and "OUT OF" in the right meaning of rate of change of magnetic flux. Again, when he had the coil picking up the nails, 3:13 he was absolutely correct when he said, " we make electrons RUN AROUND this wire", as that suggest the ELECTRICAL LOOP that I spoke about. But when at 2:22 his finger went straight down showing the magnetic field went down into the coil, there he should have said that the electrons going around the loops of the wire would create magnetic loops going AROUND the coil through its central orifice/ opening and not just straight down. When he showed the standing waves using the mechanical arrangement at 16:36 Sir Lawrence Bragg said that each wavelength included two LOOPS. Again I am afraid to say that the model is not an exact model of an electromagnetic wave as the Potential Energy is stored in the rubber at the central axis and the moving weights the kinetic energy and there are no LOOPS anywhere in that model. Those we see are not loops, but a sinusoidal shape where the intensity of the motion goes positive and negative but not in a loop. In an electromagnetic wave each wavelength does have two full LOOPS but they are not in the forms Sir Lawrence has shown. An electromagnetic wave proceeds to use the loops as shown by that transformer experiment where the coils included the FULL ELECTRICAL FIELD OSCILLATING LOOPS and the iron paths contained THE FULL LOOPS OF THE OSCILLATING MAGNETIC FIELD . It is E/M linked and curling loops that reaches the receiver from the transmitting antenna. Loops, always full loops. When at 1:05 he described waves using matter and electrons and electromagnetic fields do not use any matter, he should have hinted that the VOLTAGE at the antenna would create a voltage PRESSURE and it is the voltage field that can be radiated into space where there is no matter. But voltage pressure on its own will arrive at distant points but will never carry any information in that CONSTANT pressure state. But the RATE OF CHANGE OF PRESSURE which is related to RATE OF CHANGE OF ELECTRIC FIELD well now the rate of change of electric field is what one can use at a distance . A whip or a loop antenna can have fields due to voltage pressure or current flow in them but it is the rate of change of the Electric Fields or Magnetic fields LOOPS that can cover the distance in space where there are no particles, What is more, it is the RATE OF CHANGE OF ELECTRICAL AND MAGNETIC FIELD THAT CAN CARRY OUR INFORMATION. Well, really the rate of change of an electrical loop is really a special form of current , a special current, a little different from a conduction current, the latter moves where there are particles but the current due to the rate of change of electric field exist where there are no particles. Recently I tried to make an electro-mechanical model of an electron whose characteristic will cause the "model " to behave as the real electron behave. In this model I had to include, Mass, negative charge, but not in one central mass, but distributed negative charges on a flexible membrane which will cause the many elemental negative charges to oscillate on this flexible membrane, Well, as the elemental charges oscillate they create a circular magnetic field around them and as a whole the mode of vibrations are similar to the higher modes of vibrations in a tuned high frequency cavity. These voltage vibrations creating the electrical and magnetic looped fields are biased in their voltage potential because of the accumulated negative charge of the whole electron. When stationary the mass and charge and the biased E field are available to the outside world but not the magnetic curls in different orientations, When the electron as a whole is moved by shooting it or under the influence of an external electric field or when an external magnetic field is moved towards it, the magnetic loops line up and the moving electron will create a curling magnetic field with its direction of motion felt in the outside world. I have tried this model to explain the working of Motors, Generators, transformer, back emf in inductances, mutual inductances, capacitors , heat radiation in resistors , light emission from red hot metals , It seem that in its form, my model can show mass characteristics and also wave motion characteristic. I should publish this, as through its simplicity, it offers quite a few explanations why the electron behaves as it does in any of what Sir Lawerence Bragg described in this video.
@GODT1TAN6 жыл бұрын
I'd like to hear more about your model
@AntonioTFernandez6 жыл бұрын
holy crap thats a lot of writing, isaved this on a docx ill read it later thanks for taking the time to explain concepts that are important and elusive
@Me-qh2ux5 жыл бұрын
@@AntonioTFernandez on the other-side of the planet there is someone like u who did the same.. and its me
@elams18945 жыл бұрын
Hi, I read your comment and you seem well versed in field theory. Firstly, can you define an electron and what is a negative "charge". In your model, are you not describing a capacitor? Cheers
@Kalumbatsch5 жыл бұрын
I'm sorry, but that's just a load of babble.
@DevRajyaguru-lx8pi20 күн бұрын
Thinking through experiments is the first stepping stone in science! Gradually you build up intuition to understand more complex phenomenon and sometimes even get the counter-intuitive thoughts. But all starts with this. And finally ends up in an abstract world of mathematics, where you see the ultimate truth, leaving behind what you even started with.
@alexandrpetrov11103 жыл бұрын
This is a fine demonstration why fundamentals need to taught by great masters and not grad students.
@robertolarios41995 жыл бұрын
Really a privilege to learn from a Nobel Prize.... And yes, he´s the one (with his father) of the Bragg´s Law !
@algorithminc.88503 жыл бұрын
Wow ... a wonderful find ... of real quality ... both this video and your many archives. Thank you.
@mostafaabdelaziz23164 жыл бұрын
You changed my way of thinking about EM waves...really better than modern explanations with animation
@nadmey90996 жыл бұрын
How beautifully demonstrated. Good old days
@MN-sc9qs6 жыл бұрын
Great public demonstrations!
@generuffalo43746 жыл бұрын
50 Hz ?? ( @ 4:56 ) NOW the British accent MAKES PERFECT SENSE This is ABOVE and BEYOND anything, and everything I have viewed on KZbin thus far
@RWBHere2 ай бұрын
It's partly a refined early 20th Century Adelaide accent which had been influenced by his educational environment. Most of the world uses roughly 50 Hz for its electricity grids. North America is one of a minority of places which use 60 Hz instead. Each has some advantages and disadvantages. For instance, coils, motors and transformers can be slightly smaller at 60 Hz, but transmission losses are lower at 50 Hz.
@jamesleem.d.74426 жыл бұрын
This guy "Coates" made a great straight man: Rigid facies, never smiled, always immediately on cue. I laughed so hard I fell out of my chair here in the lab. Great teaching !!
@alwayscurious4136 жыл бұрын
Great spot. He appears on many such videos and was an unsung hero. He instinctively knew he was not the star of the show and so got on with the job classic style. Same thing happens in rock concerts too when a roadie comes flying in from stage left to catch a falling microphone stand etc, change guitar. Morecambe and Wise lampooned this kind of thing with the singer Shirley Bassey where they wore the obligatory brown labcoat used to denoe the role of the 'unsung'!
@jaymzs82219 ай бұрын
Maybe not the most charismatic gentleman but I do love all the demos! Helps the simple mind (like my own) grasp these abstract phenomena.
@dominicestebanrice7460 Жыл бұрын
Thanks for posting this for free public consumption; it is really remarkable. Quick Q: is there a modern equivalent to the Klystron apparatus used here? Put another way, how would is this demo be replicated today?
@Mark-xq6ux5 жыл бұрын
This really is amazing. It visualises something invisible and helps understanding electromagnetic waves. Thanks a lot.
@kidschannel66142 жыл бұрын
I have to say that this is the most simple and exciting lecture I've ever taken in my entire life. I just really hope that physics is taught in this way all around the world to make new scientists.....
@MasterMindmars3 жыл бұрын
At 15:45 there is difraction. As the waves pass through the holes, they are deviated an angle and interact constructively and destructively, creating an interferometry pattern.
@udaykerkar7074 ай бұрын
From (GOA) INDIA Lot of thank to Royal Institute of science London This is way of demonstration I am expecting from knowledgeable person and that is right way of teaching. Lots of thanks to sir Lawrence. That's why I didn't likes our Indian Education system. You should teach small small concept by demonstration and not quantity of syllabus quality Of syllabus is important.
@odal677011 ай бұрын
15:29 Anybody knows how far left or right you can go before the receiver stops altogether? How wide is the range of the em waves at the distance Bragg is at?
@ejmakela75252 жыл бұрын
What is the name of the contraption that was used to demonstrate standing waves around 16:10? My American ear couldn't understand the term(s) that he used. The device is so beautiful!
@kokomelon3807 Жыл бұрын
dayyyyyuuuuuuum, waves are waves after all! This is cool, maybe Im bias as I already knew most of it but dang I didn't know all these stuff. It's my first time seing that in action aside from visible light!
@zenersmytok36192 ай бұрын
Those were great demonstrations.
@oedu_limaa2 жыл бұрын
Aula incrível! Poderíamos criar um canal com dublagem em português br
@npsfam5 ай бұрын
Superb presentation. I am a radio person and I still learned and relearned this important subject.
@mrslave415 ай бұрын
12:28 “Polarization” I don’t get it. What creates the direction of the electromagnetic wave propagation? The wave is traveling from right to left. But why would it go up and down versus left and right? What’s causing that?
@inspirationalmarvel Жыл бұрын
This is too much for just one video 🎉🎉🎉thank you so much best science video ever watched on KZbin by me
@ovalwingnut10 ай бұрын
What a wonderful career. Helping others "to understand"... 500 good human points awarded - posthumously I wish I was better at math & engineering. I wasn't so I had to settle for working at Boeing
@maxasaurus30088 ай бұрын
Interesting demonstrations, thank the physics gods someone had the forethought to record it! The intro leads me to hope there might be one or two more topics covered. ❤
@brahimimohammed94187 жыл бұрын
Great Video many thanks
@munivoltarc6 жыл бұрын
It was a wonderful insightful practical explanation, could any body please tell me what the apparatus that is producing electromagnetic waves, i couldn't able to heard properly the pronunciation.
@carmelpule69546 жыл бұрын
It is a low powered klystron working using velocity modulation. A device called magnetron may also be used as they use in microwave cookers. The latter is easy to operate but do be careful as they are dangerous.
@karthikr30446 жыл бұрын
Klystron,or u can use magnetron from a microwave oven
@mgabrielle23436 жыл бұрын
@@karthikr3044 Long as you don't get your brain in the way or it will fry up like an egg from grey to white matter. Stop fooling with things you don't understand, leave these to the experts like myself.
@karthikr30446 жыл бұрын
@@mgabrielle2343 sorry brother,I didn't get what you said 🤔🤔,it's a klystron isn't it?
@anabelcamacho65845 жыл бұрын
real knowledge is pleasurable to receive
@VPXM20125 жыл бұрын
This knowledge is actually just a description of all the stuff people should know. It's like going to a restaurant, and the waiter is spoon feeding you.
@yueibm6 ай бұрын
Could it be causing confusion when the early near field / reactive field / magnetic induction demos (e.g. at 6:00) are shown while saying "electromagnetic wave" and "space" when in actuality the demos are not designed to be good radiators?
@planktonfun16 ай бұрын
This is the best explanation teachers couldn't do today
@markwilliamson91993 ай бұрын
Very proud of Lawrence Bragg, Adelaide Australian born and educated. He and his father put Adelaide Uni on the map in Physics
@natarajsetty8513 жыл бұрын
In my school age if I could have this kind of teacher I could have become a great scientist
@dinnade93385 жыл бұрын
Love this video.. These days we need more experimental videos likes this ... not sure why this got 40 dislikes?
@Number6_2 жыл бұрын
How do you know it got 40 dislikes?
@aronhighgrove4100 Жыл бұрын
@@Number6_ Dislikes were still visible years ago.
@Welcometothemandela9 ай бұрын
This was a really interesting and great video. He was able to explain things very well, kept me interested in what was going to happen
@NUKE-W.E.F. Жыл бұрын
Got to hand it to the Royal Institution Of Great Britain, they make some very informative videos!
@islamzohny41667 жыл бұрын
it's amazing explains .. thank you Ri Archives
@mktwatcher7 жыл бұрын
Question, didn't Sir Lawerence Bragg in his demonstration show that microwaves could be focused with an optical lens? I realize that radio waves are a form of light ( packets of energy ) in the form of electromagnetic waves falling at a place on the EM scale where the waves are longer than the visible we're able to see which are shorter waves on the EM scale. But, the only thing I currently see online are either new meta material developed by MIT that can precisely focus microwaves and some other references fresnal lenses, plano fresnal plano lenses, or slotted fresnal lenses can focus microwaves. It could be that the lenses he used he used was a glass fresnal lens but that I Just couldn't see because of the quality of the film transferred to digital video. Thank you.
@alanpartridge21406 жыл бұрын
L G Ignore the fact that the lens used was also an optical lens. The same effect could be achieved with a suitable shaped block of paraffin wax. Let me know if you haven't understood and I'll give you a more detailed explanation.
@alanpartridge21406 жыл бұрын
Likewise the Aluminium mirror does not have to be an optical mirror.
@glutinousmaximus6 жыл бұрын
... It doesn't really matter that the waves happen to be microwaves - any part of the electromagnetic spectrum with be similarly affected.
@bradley58195 жыл бұрын
L G I heard X-rays can’t be focused with a lenses
@comic4relief Жыл бұрын
9:53 Very interesting. What if other materials were tried there?
@VoidHalo6 жыл бұрын
No captions? This is surprising for RI. People with hearing problems should be able to enjoy these.
@RiArchives6 жыл бұрын
We definitely agree but are very limited in terms of resources. We were very kindly provided with funding to digitise these incredible snippets of archival footage but it didn't quite cover the cost of creating subtitles. Fingers crossed we'll get to unlock some soon. We've also enabled community contributions on all out videos, where some kind souls have volunteered their time and talents to provide closed captions.
@VoidHalo5 жыл бұрын
Is there any way to volunteer to add captions?
@RiArchives5 жыл бұрын
@@VoidHalo Yes! We have community contributions turned on for our videos, so you can click on the three dots under the bottom right corner of a video and select 'add translations' in the drop down. For this video, it would take you here - kzbin.info_video?v=Vwjcn4Vl2iw&ref=share
@kapsabet3 Жыл бұрын
The best physics lesson I ever had. Thank you.
@БогданСташинский-в5с6 жыл бұрын
Супер! Красивые опыты. Сейчас одна компьютерная симуляция.
@Verschlungen6 жыл бұрын
Of the various comments, I believe yours is the only one that touches on the most important aspect: namely, that "one computer simulation today" cannot possibly compare with a demonstration like his that uses a wide variety of beautiful physical equipment!
@krishnasree20536 жыл бұрын
Sir excellent video sir I have a doubt I want clear explanation of frequency in communication and frequency in electrical 50 hz
@glutinousmaximus6 жыл бұрын
Quite brilliant demonstrations! Thanks for posting!
@otilium75032 жыл бұрын
A very good demonstration of what light really is. A blazing magnetic wave!
@edgarfov2 жыл бұрын
Incredible teacher. Such a clear demonstration, beautiful apparatuses. mechanical heaven for me. tnx.
@vahagnmelikyan2906 Жыл бұрын
Is it possible that magnetic field is disturbance of ether? To me sounds like when a charge is moving its like a jet moving in air and causing circular waves around it. Maybe there is ether that is being disturbed by a moving charge creating waves?
@b43xoit2 жыл бұрын
Are those windings in the middle shorted out?
@Gruntol56 жыл бұрын
Waves from visible down to gamma are also referred to as 'photons' - the wave/particle duality. At what wavelength do we stop referring to them as photons, and why?
@julioduran26156 жыл бұрын
Good demonstration about electromagnetic waves. Thanks for the video.
@yanaungmoe62946 жыл бұрын
11:20 How is the apparatus set up, so that the resultant EM wave's polarization is vertical?
@chuckcrunch13 жыл бұрын
vertical element in the horn . basically a little rod in a vertical orientation
@Narigopia3 жыл бұрын
Close caption shows binnacle, finicum or vannakam model. What is the correct name of that mechanical contraption where Bragg shows the nodes and loops concept and how is constructed?
@PinkeySuavo8 ай бұрын
I dont get the experimemt in 11:40... How the hell electric field wave is 2d? I just cant imagine visuslly it... With sound waves its easy to visualise that because it goes out like a sphere. On videos of shock wave it can be seen nicely. I thought light can be visualised similarly but it looks like its completely different.
@robertgift6 жыл бұрын
Interesting to see demonstrations! Thank you.
@AaronHollander3146 жыл бұрын
Are there "photons" in wavelengths other than visible light that act like matter?
@Mr69sideshow6 жыл бұрын
Photon's, the particles that make up light, don't behave like particles of matter. They can pass right through each other, and they don't bind together to make bigger structures.
@AaronHollander3146 жыл бұрын
Are their photon-like particles in any other wave length or is that unique to the tiny visible range?
@Greg_Chase6 жыл бұрын
Starting at 4:25 he explains how an EM (electromagnetic) wave is created off the oscillations in the antenna. He glossed over something. About 99.9999% of people on Earth are unaware of this issue. I'll use "C" for current and "M" for magnetic field below. If space is 'empty', and you listen to him saying "the antenna has an electric current (1C) that is oscillating up and down, and that creates a magnetic field (1M, next to the antenna), and that magnetic field creates oscillating current (2C, next to the magnetic field but further from the antenna), and that creates a magnetic field (2M, next to the 2C electric field and still even further away from the antenna), and that creates an electric field (3C, next to the 2M magnetic field and still further away from the antenna) and so on, until enough "electric field creates magnetic field which creates electric field which creates magnetic field which.....which finally reaches the receiving antenna." **LET'S REVIEW THE FACTS** 1) the original, oscillating current flow occurred in a metal antenna 2) the original magnetic field was created next to the metal antenna 3) from that point on, there is 'nothing in space to create the electric fields and magnetic fields in a daisy chain to reach the receiving antenna **WHAT THEN IS IN "EMPTY" SPACE THAT ALLOWS THE CREATION OF ALL THOSE magnetic fields and electric fields one after the other between the sending antenna and the receiving antenna?** I've got an electrical engineering degree and they glossed over this in university. The virtual particle field, aka the Zero Point Energy Field (ZPF) is the medium that allows the creation of all those 'in between' magnetic and electric fields. en.wikipedia.org/wiki/Virtual_particle . . .
@dlwatib6 жыл бұрын
I came down here to say the same thing but in much less detail. If electromagnetic waves propagate through space, then that's proof that space isn't empty. We may not be able to otherwise detect that electromagnetic medium, but we know it has to be there. We're like fish that can't detect that we're swimming in water because it's all around us.
@AJAdkins996 жыл бұрын
Greg Chase have you heard of a little thing called...quantum physics?
@Greg_Chase6 жыл бұрын
@@AJAdkins99 Check out QED (Quantum Electrodynamics) and SED (Stochastic Electrodynamics). en.wikipedia.org/wiki/Stochastic_electrodynamics I'm not sure the point of your question as there were no details, but if you're unsure of the existence of the virtual particle field, theoretical support comes from Heisenberg back in the year 1927, (the Uncertainty Principle) so the theoretical underpinnings of the Zero Point Field aka the virtual particle field have been with us for nearly a century. The 'magnetic lines of force' are made possible by the Uncertainty Principle in terms of theory. **SCENE** You're on a spacewalk from the ISS. You have bar magnet M1 in your left hand, and bar magnet M2 in your right hand. You move your hands near each other. Recall this is in 'empty' space, by that I mean what 99.9999% of people on this planet fully believe is 'empty'. You're on a spacewalk, in vacuum. In 'empty' space. Suddenly the two magnets M1 and M2 snap together. How did magnet M1 'know' magnet M2 was there? And vice versa? 99.999% OF THE POPULATION OF EARTH: "Because of the magnetic lines of force." **REALITY** -- Let's put the 'physical' back in Physics. The virtual particles were polarized by the magnets. The physical connection in the vacuum space between M1 and M2 was made by the virtual particles content between them. **POLARIZATION OF THE VIRTUAL PARTICLE FIELD** -- see en.wikipedia.org/wiki/Vacuum_polarization 99.999% of the people of this planet, if you ask "how does the electromagnetic wave known as Light traverse the distance from a distant star to Earth?" will say "The photons from the star follow a ballistic path from the star to Earth." 'Ballistic' meaning linear path from the star to Earth. That's not a wave, 'Ballistic'. Waves are waves. Ballistic path means an original photon *"Po"* from the star travels the entire linear distance in space from the star to Earth. What I'm saying is, 99.999% of the people on this planet believe that a photon on a star takes a linear (ballistic) path from the star to Earth. Travels the whole distance, a photon, from the star to Earth. So I put it to you: Which is correct? Ballistic path or wave? HINT #1: Here's how waves are made. The source of the wave goes UP and DOWN like the electric current in a vertical dipole antenna But the wave travels ORTHOGONAL to the vertical antenna. GO TO TIME 1:20. kzbin.info/www/bejne/aZamnpmXra6doMU The wave machine is conceptually identical to a vertical dipole antenna in terms of how a wave is started on an orthogonal journey out away from the antenna. HINT #2: You're a surfer 100 yards from the beach. 'Rolling waves' are in the water, heading for the beach. Consider a molecule of water "Wm" right next to you. When a rolling wave moves past you, heading for the beach -- does "Wm" move from your position all the way to the beach? Or does Wm move up, then down with the rising and falling of the crest of the wave and stay in your relative location after the wave passes? . . .
@gatyair826 жыл бұрын
Luminiferous ether.. duh
@samuelkrauthamer31116 жыл бұрын
Greg Chase w
@JadeHare12 ай бұрын
Wow!! I would love to have this class at high-school!! 👏
@QaaFvcc5 ай бұрын
Oh my lord give me more knowledge and wisdom. This video is well presented and got me more excited to purse master in Communication wireless.
@mamamia85115 жыл бұрын
true knowledge is pristine and clear
@MyCh2025 Жыл бұрын
Back in time things were real and universities produced real engineers.
@taboosaboo6 жыл бұрын
Of Course now it makes sense. 15:00 . The double slit experiment, is not a wave. It is reflection. Straight through. One bounce. 2 reflections. 3 reflections. And so on. Matter is like a thick hallway to light, even a thin sheet.
@JohnVKaravitis6 жыл бұрын
Please clarify your statement.
@ZopcsakFeri2 жыл бұрын
Did I just watch a person bragging for 20 minutes straight? I have to admit, I thoroughly enjoyed!
@Vinodsinha196 жыл бұрын
Very good lecture ! befor , I watching this video I don't know what is EMR after I know about what is EMR . Thank you sir
@KR725345 ай бұрын
Wonderful piece of experimental physics. Formulas can never teach this.
@k.v.saimadhav42515 жыл бұрын
superb demonstration and experiments
@sunahangrai3601 Жыл бұрын
this video series is a great series on experimental basis for chemistry
@NvTwist4 жыл бұрын
K need some assistance, polarization showed that vertical slits of conductive material conducted (absorb) the waves & at 90° they pass thru..... the double slit (vertical) demo the waves pass thru the slits.... was it made of a nonconductive material? Appeared to me aluminum but I’m missing something here.
@Stephen_M. Жыл бұрын
Great video! Answered several of my questions.
@mikemoise65396 жыл бұрын
This was amazing. Can someone please explain the lens and sound waves? Was that sound waves or electromagnetic waves being focused? Clearly I've seen it done with light but I can't wrap my head around how it works with what he did?
@alwayscurious4136 жыл бұрын
The EM field was being modulated (i.e. a ripple was applied to its amplitude with the frequency of the ripple corresponding to that of an audible note). The ripple was set to be low enough to be barely heard by the microphone but it could be picked up whenever the beam was modified (by a lens or interference) so that the ripple was large enough to be detected. The lens increased the amplitude by focussing all the light into one place, the double slit achieved its effect via interference where the amplitude of the ripples when intefered can be increased by a factor of up to x4.
@anomalyp858411 ай бұрын
What I don't understand though is that an electric field is limited in range, the force charges experience within that field diminish with the distance to the source charge. How is moving that source charge then able to emit it's 'field' outside its own boundaries...