Accelerating Charges Emit Electromagnetic Waves - "Light" - Radio Antennas! | Doc Physics
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- เผยแพร่เมื่อ 12 ก.ย. 2024
- Every charge that accelerates emits light that indicates how it has been accelerating. This can be used for radio and other long-range communications!
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Dude this is the best explanation of how electromagnetic waves are emitted. You killed Yale and Stanford . . . . A big thank you from an engineer who uses this stuff on the daily and now understands it better!!
Agreed, one of the better explanations available
This is only repeated story without thinking. Antenna is reactive part of system , and all science story is wrong. Is impossible to have max value E and B field at same time, also current and voltage. Ok, we use horizontal plane to represent B field , but that do not have any sense with phase shift, only with interpretation. Write new diagram, with B min at point of E max and that is correct. Only book with that presentation is correct, but maybe only few contain valid picture.
+ Electrical Disturbance - I think you are correct: Why should B be in phase with E? I thought the B field exists only for the stationary observer who feels the E field changing. The maximum rate of E field decay is felt by the observer when the slope of the E "wave" is steepest, ie when the wave cuts the x-axis; Am I right? So, at E=0, the B _should_ be Max. Therefore, E and B _should_ be 90° out of phase. Why do all textbooks show them in phase? What am I missing?
Robotix Sir I have one don't if an accelerated charge produces electromagnetic field, we can see the power transmission lines carries accelerated currents then in that case the electromagnetic waves should travel long distances and induce current in all the conducting material around that lines should induce current like as EM waves from antena induces in receiver antena. Please clear this dout
@Electrical Disturbance re:"Antenna is reactive part of system , and all science story is wrong. Is impossible to have max value E and B field at same time" . I will submit, ED, that the folks who researched direction finders in the 1920's onward have some idea about the E and B field phase relationship. I suggest you check out "Direction and Position Finding by Wireless" written by Ronald Keen in 1922. Here is an online source: archive.org/stream/directionandpos00keengoog#page/n6/mode/2up
The fact that you take the time to do these videos and share them reflects the great character you must have! God bless you sir!
This guy makes physics so much fun! :""D
I laugh while learning, that's a plus.
i wish all my professors sounds as enthusiastic as you, it helps a lot listening through the whole thing. And great content! Thank you!
You know what surprises me more about you is the time you take to share to all of us orphans of mother science !
One thousand thanks !
Marcos Rivas That's a nice turn of phrase! You're welcome!
Resonance. I have a video on it. Get ready to fall in love with the universe all over again.
Thanks for the props, too!
👁⭕👁
YOU'RE WHAT'S RIGHT IN THE WORLD! I never thought I would laugh and actually enjoy learning physics. THANK YOU
ME TOO!! I NEVER LIKED PHYSICS,BUT THIS GUY NAILED IT!HE SOUNDS LIKE RYAN REYNOLDS IN DEADPOOL HAHHAHAHHAHA
Great video.
Greetings from Slovakia!
Are you on the West side?
4:44 "Strange because of diarrhea" Like wuuuut Scoob!!!! Lol
It always bothered me as a student that how it physically happens and your video helped me understand that. Thanks a ton sir, your fun way of teaching makes learning a fun experience :)
OMG, you explain this so well that I even got emotional after watching this. THANK YOU so much!
@7:30 "This pissed me off a little bit."
Sums up how I feel about everything I've learned in physics thus far.
Probably the most entertaining video I have seen in months! Thanks for creating this, now I understand :)
Simple and entertaining, just as school should be. Man, must it be so tiring to entertain while lecturing! Thank you, you earned a subscriber
I LOVE this explanation of electromagnetic waves. It uses my previous knowledge of the right-hand rule to intuitively explain how EM waves are created and propagated, which is very interesting! Thank you so much.
This is how i imagine Scott lang teaches physics to Cassie😊 you're amazing
I have pumped almost every video out there to properly understand how propagation works , by far this is the best explanation ever !
I suppose so. And you're right - it's hard to imagine a source that doesn't have ANY linear portion at the output. But maybe it's a shielded cable where the signal is coaxial with the ground...
Either way, no antenna means extremely inefficient broadcast. This leads us back to an impedance matching discussion. Fun!
Let me just say that you earned my respect. It seams as your words are always trying to keep up with your brain. but you think very fast, so you speak very fast. But I must say again: you have my respect. Please, keep making videos like these. "Thinking mankind" thanks you!
Let me propose a question: could I shift a visible light frequency to an invisible one (and vice-versa)? For example: can I turn visible light to UV light?
Thanks! Shifting light would mean absorption and re-emission. As long as energy is conserved, you can surely do that. Visible to UV is an increase in energy for each photon, so you'd have to have something feeding the beast, as it were. If you look up how fluorescent lights work, you'll see that shifting frequencies down is not only possible, but quite commonplace.
Doc Schuster Or you've got to be really far away and the light source has to be pulsating and moving towards/away from you fast enough for a Doppler Shift into the invisible.
*****
Brilliant! That's a much better answer than mine! Not a convenient procedure for the lab, but quite commonplace in the universe.
This is the best explanation of electromagnetic waves I've found on youtube. THANK YOU VERY MUCH!!
Incredible video......I have been in radio communications my entire work life, and that's the best explanation of RF propagation I have ever seen! Great job, keep them coming! There's a lot more I need to know!!!!
His reasoning is incorrect.
@@amirq25ify omg don’t say that! I’d hate for all those billions of radios around the world to suddenly stop working!
I was so surprised when you mentioned Slovakia. I live there and sometimes it seems like it's a place forgotten by the world. It made my day. Keep the great work up!
+Tomi Adamec Oh, what a horrible feeling! Happy to help!
I knew all this already (more or less) but you still deserve a like for the presentation. Well done. Never lose the energy you have.
What is represented is not the real manner in which E/M waves are transmitted , but it is only a simple time representation. The E/M waves are generated within the transmitter as LOOP of voltage hence current creating a LOOP Of magnetic field. The antenna radiates ELECTRIC LOOPS and MAGNETIC LOOPS curling together as CurlH= J+ dE/dt and note that J and dE/dt are found in an ELECTRICAL LOOP and the CURL OPERATOR means that the ELECTRICAL loop is Curling the MAGNETIC loop.
This diagram of electric and magnetic fields do not indicate the function Curl H= dE/dt.
Many books should revise their interpretation of the E/M wave in space.
Note everybody will do better if they study the E/M loops in a waveguide and that relation in how the E/M waves are curling loops repeated a million times is the real structure off an E/M wave in any electrical appliance that works. IT IS ALL LOOPS AND NOTHING BUT LOOPS.
Those issues that do not curl and E/M wave together has no power associated with them and they are charges and magnetic fields only used as MEMORIES as the DC charge in a capacitor, which has no loops of Electric field but it has only a memory. The same with a magnetic loop, a magnetic loop on its own is only a memory.
That is a really interesting comment - got me thinking about the CURL side of things related to the linear oscillation of charges along a wire. We know that a moving electric charge creates a magnetic field that is looped around it - we can think of the magnetic field arranged cylindrically around the wire. To me that's where the 'curl' of the equation is in all of this - do you agree. I prefer to think of the magnetic field as 'not being a phenomenon of its own (like say gravity is) - to me a magnetic field is just the curly part of an electric field. If the electric charge is stationary (relatively to an observer) then its magnetic field disappears hence its the electric field that is the 'real' thing. I think we might both agree that when it comes to EM theory - it soon gets loopy.
@@alwayscurious413 What has always been a problem for me is that the current and the potential in a dipole antenna as you have is not in phase. When the potential between the ends are at their highest the current has stopped so how come the magnetic field is at it's highest then?
I have mentioned this to other people and been told that I am correct in the "Near field" but it changes when it comes to the far field.
(Near field of cause being within one wave length and the rest being far field). If so how does it change at the border?
I have even been in a conversation (online) with a person (with PHD etc.) that claim that propagation in the near field is instant (not with speed c). He claims (and has a paper showing it) that he and many other have verified it experimentally. This also does not appear correct to me. I do not easily have the capability to make the setup to verify it. What is your opinion?
@@leonhardtkristensen4093 - thanks I’ll look into it and get back to you. As an aside IMHO there is no near or far field as far as light itself is concerned. It does not ‘know’ where it is or what it is allowed to do (eg so called wave particle duality.). We use these models to assist with the mathematical modelling of the amplitude distribution we are likely to get when we observe it.
@@alwayscurious413 Having studied a little more I have found out that what you are talking about is some thing called curl. I have been thinking about the direct magnetic field and the direct potential. I believe to be able to calculate on it it is either a necessity or at list an advantage to use curl. It is a little above the calculations I am used to and remember how to do.
@@leonhardtkristensen4093 - yes the curl of the field is a critical parameter and heavily utilised in maxwells equations. With curl we can think of water circulating in a whirlpool - it’s not going anywhere (that is the divergence) but it has a property we can see - a circular rotation. So when a charge accelerates back and forth along a linear length of wire it has to create a ‘curled’ magnetic field around the wire. If we ‘curl’ the wire into a coil then the circular motion of the charge passing through the coil (solenoid) creates a linear magnetic field run John through the centre of the coil. So oscillating electric and magnetic fields are related via this strange curl effect. When we create light (radio wave) from an antennae someone else on YT (genius) described the light emission as being related to the ‘shearing’ of the changing fields. No shear then no light. It is fascinating stuff. In terms of the math it can all be understood by waving your hands (trust me) - the maths just puts the numbers in!
For years....I have tried to understand EMW. This video creates that understanding.
I'm so happy to hear that! Thank you!
He also hit upon a major fallacy of "science." The meter used to be defined based on the length of a single metal rod at a certain temperature. All other meter sticks were made to fit that length. It was a unit of measurement based on a material. Then they decided that light has a "constant velocity" and used the fastest measured "velocity" as the constant, which occurred when measured in vacuum. Then they re-defined the meter to be based on the "velocity of light" while still claiming light has a constant velocity in vacuum. The problem with this is that light does not have a "constant velocity", even in vacuum. The rate of electromagnetic induction (erroneously called velocity) is determined by the magnetic permeability and dielectric permittivity properties of the medium through which the waves are propagating. There is no perfectly homogeneous medium in the entire existence of nature. The vacuum is not a perfect vacuum. There are various atoms floating around in different concentrations in different areas of space. Sure the difference between the actual rate of propagation and the assumed rate of propagation is minute enough to where it is irrelevant at short distances, but when cosmological scales come into play, this error becomes magnified. The truth is, our distance measurements on the cosmological scale are truly undeterminable because we have no way to determine the variations of the medium between the observer and the object being observed. We measure the time it takes for an em wave to propagate to and reflect back to the observer and then used the "constant velocity of light" to determine the distance. It is funny how we actually utilize time to measure distance. Further complicating the matter are erroneous interpretations of redshift, which can have several causes; not just the doppler effect.
learning EM waves has never been so exciting..Good explanation full of coherence and humor. THANK YOU
Awesome. I am so happy you are doing this! My students are going to love this when I tech EM next fall. Thanks.
Dude...or should I say sir, your explanation is the best on youtube...you were able to deliver this boring topic coming up in my test using humor(grade8), intelligence and most importantly..with absolute simplicity....cheers! Many thanks..like
Saying hello from the great country of Slovakia.
+Šimon Šimonn My son just said, "SLOVAKIA!!!" Yay!
What's something like great in Slovakia.. it's not ex ussr state
@@jitendranihaliya5677 former yugoslav however
@@tord1508 So what yogaslavia was not great empire ..
Thank you for making these videos for us; they're tremendously helpful for university physics!
your cool way of deliver plus the information within makes this an informative and relaxing video.
I love how enthusiastic you are!
I'm so happy to hear it. I'm sure when I get to synchrotron radiation, you'll be well beyond that, as well. Maybe YOU should make the video... Keep learning!
5:40 I thought that current is going from positive to negative by convention. So it would also be in the direction of the electric field....How come its opposite on your drawing?
Ahh, that's because electromagnetic force travels the path of leas resistance. You are correct both flow from positive to negative but electromagnetic force travels in a circular motion. The fact that he drew the lines in an opposite direction seems to be what threw you off. Imagine a coil being wrapped up alongside the current flowing in a straight direction, that might make more sense. You can visualize the flow by drawing ang an imaginary line through the arrows left to right. The imaginary coil (EMF) is indeed flowing left to right. Draw a coil so you can physically see the directions going up, down, left, right creating a circular motion.
@@rodrigogomez5035 Are you saying he drew the arrow in the wrong direction? Also, what is electromagnetic force? Did you mean to say that electromagnetic _waves_ travel in a circular direction?
Your videos are awesome! i enjoy learning physics from your videos because my professor is so BORING and I get nothing out of him. honestly I've learned more in a day from your videos than I do in a month from the class I paid for...I have an exam coming up so expect to see a boost in views lol!
Guys, do me a favor and don't question his awesomeness lol. The doc's good at promoting healthy INTUITION. When you do it mathematically, things might be somewhat skewed, but his presentation was on point. :)
I wish all of our teachers were this much exited .
Thanks for letting me know, Tom! You're welcome. Keep up the hard work.
Well, the presentation was nice but I have two doubts: -
1) You say that the current is maximum when the electric field is maximum. But, we know that in simple harmonic motion, the velocity is maximum at the mean position. Thus, when the charges are maximum (and we have maximum electric field), they should produce no current. Hence, the rate of flow (velocity) of charges i.e. current should be maximum when electric field tends to zero. Hence, maximum magnetic field should be observed when electric field tends to zero as the magnitude of the magnetic field depends on the velocity of charge.
2) I did not understand why the electric field should move forward...
Gramercy...
I love your enthusiasm!!!!! THANKS>> I LEARNT ALOT!!!!
I'm glad to hear it! It's easy to be enthusiastic with such great students.
This is a beautiful explanation! I've struggled with understanding Maxwell's Equations on an intuitive level for what feels like forever, and now I finally feel a bit confident on the topic. Thank you so much!
The magnetic field goes around the antenna experimentally. The sideways pointing magnetic field atrocity probably started in 1888 by Oliver Heaviside.
subscribed.... You sir are a rockstar. you love this stuff and I appreciate the time that you put in this small video. your manner of teaching has cleared up years of confusion in just under 15 minutes. absolutely lovely!
Finally I have found true explanation of those sinusoids. No YT channel pay attenention to question fwom where they getting from. But now I got it. Thanks a lot :-)
Great question. Their amplitude is in strength of field. Only waves that have physical media have an amplitude that can be measured in distance. Nice work!
Great video. Thank you for actually spelling out how these systems interact with each other, and explaining the physics behind it. A lot of videos on signals are either wayy too specific or wayy to general.
Wow it's impressive what a focused mind can do. I think you must have a good grasp of things I'm just learning. I don't know enough about these things yet but I think it's about the pictures I took recently....you might like my latest video.
Im from Slovakia and you made my day with this one :)
i m from programing field, but developed interest in this... ur videos r super cool.. subscribed.
How does the current move down??? Its for a school project.
AWESOME. makes me want to spend my life getting to know all this weird stuff.
Awesome video! Thank you! Does the E-field from a radiowave come from the alternating source voltage rather than the electrons in the wire then? People usually say that when you oscillate charges in a wire you get an EM wave but the way you put that wouldn't make that quite correct. You seem to say that the electric field comes from the AC voltage source rather than the charges themselves and that it is only the magnetic field that actually comes from the charges (current)?
Isn't the magnetic field at a maximum when the electric field is changing most rapidly? which is when the electric field is at zero, that's when the electric field is changing most quickly, so the magnetic field is not zero when the electric field is zero. At the peak of the electic field, for a moment, the electric field is not changing at all, and that's where the magnetic field is zero, because the magnetic field needs a changing electric field to exist. So the two fields are not both zero at the same time as you have drawn?
John, I have gone through the same reasoning several times in my life. It seems great. I can't tell you a single thing that's wrong with it, actually. I suspect the magnetic field is created a 1/4 wavelength away somehow. This point continues to confuse me. Perhaps someone more adept can address this. Suffice it to say that B and E are peak at the same locations and zero at the same locations at every instant for a light wave. BUT HOW?!?!
Doc Schuster I always thought that it's like an open capacitor, while charging there is current (=magnetic fields) but when it's full there is no more current but an electrical field, magnetic & electric fields are (in my conviction) 90deg out of phase.
What I don't understand (if both would be in-phase) is that at 0,180.. deg. all fields would vanish and then reappear out of nothing, having the fields 90deg out of phase would mean that the energy/information is always there.
Knowing that the magnetic field is c times smaller than the E field, I'm asking if this has been ever measured?
I've always been suspicious of displacement current; seems like a bunch of nonsense to me. We can always say that the zero phase angle difference is a quantum or relativistic effect; that will silence most or the science sheeple, but just maybe the foundations of electromagnetism are faulty.
Indeed, the magnetic field will be 90 degrees out of phase, if the light is circularly polarized.
That appears to be the type of light generated by this antenna.
Ok, so let's say we have a dipole antenna. Through this antenna there's electric current (because it's also connected to a feeding point). By feeding the antenna you actually make the electrons, which were before just sitting there in the conductor, move. By moving, these electrons generate a variable magnetic field (keep in mind tho that a charge does not need to be moving to have an electric field) which changes direction at every half period of time. In all this time, electrons move from one side of the antenna to the other generating a magnetic field as they move and then an electric field as they "sit" at one end of the antenna(also generating a maximum in the wave of the electric current). This is why we say that the electric current is 90 degrees out of phase from the voltage. When the electromagnetic field radiates into space, the H plane will be perpendicular to the E plane and vice-versa, so it is in SPATIAL QUADRATURE (90 degrees) and the vectors of the E and H field change direction(NOT the direction of propagation of the entire electromagnetic field) at every half a wavelength. Oh and also the whole E field being perpendicular to the H field is due to the "pattern grid" it creates in free space when radiating. Someone correct me if I'm wrong
"At the same time we've got, essentially, a current in this wire. Now thats a little bit strange because of diarrhea." HAHAHA great explanations btw, I'm a Chemistry major currently in Medical school and stumbled on your video. You really know your stuff! Thanks for posting :)
...yes. You are entirely correct. However, at low speeds, this radiation is very small. But think about the cloud chamber tracks that you've seen - they all curve in.
datz a mindblowing explanation! wow! have been always wondering about em waves but never got it ryt.
indeed this video deserves more views.
Great explanation for such great concept! I used to draw that E/B propagation wave when I was at uni, as I was a shortwave fan (dixer) it made sense to me and I got it right so far. but here the UNLOCKING piece was the timeline and and the Electric field move while a new one is generated at the source. that explains why a source cannot be a constant electric generator, unless you want a single pulse at the switch-on/off step. Brilliant! new subscriber indeed!
Hey man, really nice video, but I have one quick question. When you drew the electromagnetic field, shouldn't the magnetic and the electric field have a 90º Phase difference to each other?
I thought the current is 0 when the electric field is at its maximum, so that must mean that the magnetic field is 0 when the electric field is at its maximum, right?
Alejandro Márquez Nope , that drawing is correct , there is no phase difference between electric and magnetic field . Another thing is that in his example he just had an antenna , no circuit , the +\- ve terminals weren't connected. It's connected to an alternating power supply. So the charges keep changing creating a change in the electric field , and whenever a electric field changes with time , magnetic field is induced.( opposite is also true ).thus when electric field is max, magnetic field is max and when electric field is 0 , magnetic field is also zero.no phase diff
Now consider the alternating power supply is connected ( the two wires are connected) , now a current is present. This current lags behind the emf ( alternating power supply) by a phase diff. Of pi/2 (90°)
Now if you know what polarisation is , if this wave is polarised in a certain manner , a phase difference of 90° can be created between the E field and M field I believe .
Hope this helps.
I wonder if there is an experiment showing that a charged body, accelerated, emits a wave. Not a dipole, but a charge. It would be fundamental to see that.
The best explanation ever, happy to discover your channel. Job well executed
I enjoyed it, one of the best I've seen.
Thanks! Your channel looks great, too. I did a fair amount of proton NMR for my thesis.
A very cool video. I love your (slightly mental) delivery
You may say that every accelerated charge radiates electromagnetic energy in the form of waves. However it is not correct to say that every accelerated charge radiates light. This is because light does behave (in some ways) like electromagnetic waves, but no one has demonstrated conclusively that light is composed of electric fields and magnetic fields oscillating perpendicular to each other. No one has (to my knowledge) ever produced light by using only electric and magnetic fields.
Radio waves are made by antennas.
Photons are made by atoms.
If the frequency of a radio emission was increased to the spectrum of visible light, then the radiating antenna would not emit visible light?
Skoolkids are not told that radio waves (ie em waves) are a different animal to photons. A 10 mm radio wave is not the same animal as a 10 mm photon. Radio waves consist of my photaenos which are the radiating part of a photon. And, re the Hertzian rolling E by H nature of radiating emissions from photons, i like the work of Ionel Dinu who has analysed the Hertz experiment & he says that Hertz's interpretation of Hertz's waves was wrong, there is no rolling E by H emission. Likewise Ivor Catt says that there is no rolling E by H emission anywhere in nature, it is a Heaviside slab of E by H energy current, a TEM.
The so-called flow of so-called electrons in an antenna or in any wire is a secondary effect. There is a slab of transverse E by H energy current flowing along the outside of the antenna/wire. As explained by Heaviside, Ivor Catt & Forrest Bishop. There is no such thing as charge or voltage.
Photons have a central/internal part (the central helix) & an external part (the photaeno).
The central helix has a front end & a rear end, & is (possibly) 1 wavelength long. The wavelength is simply one turn of the helix (there is no wave).
The central helix is an annihilation of aether. Annihilation of aether gives gravitational mass & inertial mass.
The track of the annihilation forms a helix. The helical annihilation moves axially throo the aether at the speed of light c, & along its helical track at more than c.
Photaenos radiate out (to infinity) from the central helix.
Photaenos annihilate aether, hence they have gravitational mass & inertial mass.
Photaenos include a vibration (excitation) of the aether.
Photaenos propagate outwards throo the aether at perhaps 5c in the near field (approx 2 m) & perhaps c in the far field (wolfgang g gasser).
www.electronicspoint.com/forums/threads/experimental-evidence-for-v-c-in-case-of-coulomb-interaction.168813/
Photaenos radiate from fixed locations in the aether, ie from fixed locations along the central helix.
Photaenos do not have a sideways velocity in the aether, ie each photaeno is shed from the central helix as the rear end of the central helix passes.
In a free photon every photaeno is initially attached to the central helix, & later it detaches.
In a confined photon the central helix has formed a continuous loop, in which case the photaenos do not detach (the central helix has no rear end).
Electrons & other elementary particle are confined photons.
Photaenos give us charge fields & electromagnetic fields.
An attached photaeno gives a high field strength, an unattached photaeno gives a weaker field.
Hence a free photon has 3 parts, the central helix, the attached photaenos, & the unattached photaenos. A confined photon has 2 parts, it has no unattached photaenos.
Man-made radio signals are carried by photaenos, they are not carried by photons.
A photon with a (natural) 10 mm wavelength (the length of its central helix), is a different animal to a radio wave with a (forced) 10 mm wavelength (which has no central helix).
Free photons are slowed by the nearness of mass (confined photons), as suggested/proven by Shapiro (Shapiro Delay).
Shapiro Delay is due to the photaenos (from the free photon)(& from the confined photon) fighting for the limited use of the aether.
Fighting/congestion slows the photaenos & this slowing feeds back to the central helix, slowing the central helix.
I call this slowing "photaeno drag". It contributes to the bending of light. It gives us diffraction near an edge.
Photaeno drag is very strong inside mass (air water glass). It gives us refraction, & reflexion.
STR is krapp -- & GTR is mostly krapp.
We are presently in the Einsteinian Dark Age of science -- but the times they are a-changin'.
The aether will return -- it never left.
Yep. Synchrotron Radiation. We typically don't mention it in the first year classes, though.
YAAAAS thank you so much for this, I've always been kind of not okay with EM waves, because like what's moving? What's making a wave? and now I know.
Your explanation is RAD! keep up the good work
"THIS IS LIGHT!!! PEOPLE!!"
How important is this again???
close your eyes and try moving through life
Just for some channel input, I subbed at "tHiS iS a RaaAaAdioOoo" @ 11:22 lol
This is great. I wasn't planning on watching a video on Antennas but it randomly autoplayed and well.. not disappointed in the least. Love your enthusiasm and eccentric speaking style while explaining the topic. Kinda of hilarious while informative. *thumbs up and shit*
Holy shit! You just made me understand how antennas work! Thank you sir!
yay, you used slovakia :) btw love your videos, they really help with things i only kind of understood in highschool and need to understand fully now
but why does the electric field shift towards right in the first place?(by the way your videos are amazing! :)
Kunal Kulkarni Excellent. Information about the arrangement of charges (that's what electric field is) travels at the speed of light. If the charges change their arrangement, the new field will not be the same as the old field, but information about the old field is still propagating away from the charges like ripples in a pond. Very good question.
Thanks a lot! Interesting to learn about this phenomenon :)
Doc Schuster electric field is something that is present in the conductor (which propagates electrons ) and movement of electrons causes magnetic field to generate outside the conductor . so question is how the information of changing electric field propagates outside the conductor or antenna? Thanks in advance
@@VikeshPyati No such thing as an electron. Rather the field propagates. And no one has yet defined a field..
Best explanation ever! Even after 10 years and watching numerous videos, I finally understood. Thanks :)... I have a doubt: because an antenna uses AC current, the magnetic field propagates through space. That means if I use DC, its field stays around it and doesn't propagate, similar to a permanent magnet??
love your explanations you make it so simple and so appealing !
The transmitter antenna seems to be tuning fork transmitting its vibrations to the other tuning fork/antenna.
Light travels at a rate of induction through the aether. Aether transfers vibrations of light like tuning forks.
There is no aether! That is the key result yielded by the Michelson-Morley experiment. Electromagnetic radiation seems to propagate as a wave, but interacts with matter as a particle. Refer to Young's double slit experiment and Einstein's explanation of the photoelectric effect.
Classical Physics breaks down in the realm of the very small and the realm of the very large.
Thanks! And to answer 3...it seems like it should. But then...why don't we have wire/antenna visible light sources?!? I'll have to think more about it. Excellent question. Anyone else care to lend a thought?
Dude, this is so well presented
Best lesson I've ever learned in my life, I feel like a kid again.
Many thanks for the very interesting and fun way of explaining EM waves. DANG!
I LOVE your energy! This has been so fun
So that's how the EM wave is produced and propagates! Many thanks
Hello, thanks for your great explanation, I am wondering why the B field is in same phase of E field but not 90 degree lagging. By what Maxwell equation said B field is proportional to rate of change of E field.
very nice lecture.. very well explained. Congratulations
Wow. Never saw a light radio explained so well ;)
I loved every second of that! DANG
Your video is always fun to watch :)
Insane teacher... Really enjoyed!!
Currently sitting in the QUIET QUIET QUIET library and laughingg my butt offf!!! but trying not to so i sound like a little dog sneezing LOL
All one has to do is to describe the arc of a circle to get radial forces, ray deviation, and radio waves. The sine wave is forward propagation during gyrations. Electric field 2-D dispersion. If any point on this graph goes around in circles, that'd be radial.
I'm just curious, what makes us so confident to assume that the speed of light will be constant throughout time that we use it for the definition of the meter? We only officially measured it relatively recently in the history of science. Also, how would we even know if it changes given that the metric system is now based off of it?
i really appreciate you doc!!!thanku shooooooooo much for this!!!
That's how the freaking physics is taught! Wow! You're a genius!
Thanks, yo! Keep on learning.
BEST VIDEO ON TH-cam FOR SIMPLE EXPLAINATION OF WAVES!!!
I'm still puzzled about one thing- Why does the frequency of the recieving antenna HAVE to be the same as the frequency of the propogating antenna? Please don't tell me its just the laws of nature (I'd appreciate a detailed explaination). Thank you in advance
This guy is awesome.
Wow thank you very much. I have been wondered about this for soooo long!!!
Great! Great! Awesome explanation! Thanks!