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The Big Misconception About Electricity

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  • Published on Nov 18, 2021
  • The misconception is that electrons carry potential energy around a complete conducting loop, transferring their energy to the load. This video was sponsored by Caséta by Lutron. Learn more at Lutron.com/veritasium
    Further analysis of the large circuit is available here: ve42.co/bigcircuit
    Special thanks to Dr Geraint Lewis for bringing up this question in the first place and discussing it with us. Check out his and Dr Chris Ferrie’s new book here: ve42.co/Universe2021
    Special thanks to Dr Robert Olsen for his expertise. He quite literally wrote the book on transmission lines, which you can find here: ve42.co/Olsen2018
    Special thanks to Dr Richard Abbott for running a real-life experiment to test the model.
    Huge thanks to all of the experts we talked to for this video -- Dr Karl Berggren, Dr Bruce Hunt, Dr Paul Stanley, Dr Joe Steinmeyer, Ian Sefton, and Dr David G Vallancourt.
    ▀▀▀
    References:
    A great video about the Poynting vector by the Science Asylum: ru-clip.com/video/C7tQJ42nGno/video.html
    Sefton, I. M. (2002). Understanding electricity and circuits: What the text books don’t tell you. In Science Teachers’ Workshop. -- ve42.co/Sefton
    Feynman, R. P., Leighton, R. B., & Sands, M. (1965). The feynman lectures on physics; vol. Ii, chapter 27. American Journal of Physics, 33(9), 750-752. -- ve42.co/Feynman27
    Hunt, B. J. (2005). The Maxwellians. Cornell University Press.
    Müller, R. (2012). A semiquantitative treatment of surface charges in DC circuits. American Journal of Physics, 80(9), 782-788. -- ve42.co/Muller2012
    Galili, I., & Goihbarg, E. (2005). Energy transfer in electrical circuits: A qualitative account. American journal of physics, 73(2), 141-144. -- ve42.co/Galili2004
    Deno, D. W. (1976). Transmission line fields. IEEE Transactions on Power Apparatus and Systems, 95(5), 1600-1611. -- ve42.co/Deno76
    ▀▀▀
    Special thanks to Patreon supporters: Luis Felipe, Anton Ragin, Paul Peijzel, S S, Benedikt Heinen, Diffbot, Micah Mangione, Juan Benet, Ruslan Khroma, Richard Sundvall, Lee Redden, Sam Lutfi, MJP, Gnare, Nick DiCandilo, Dave Kircher, Edward Larsen, Burt Humburg, Blake Byers, Dumky, Mike Tung, Evgeny Skvortsov, Meekay, Ismail Öncü Usta, Crated Comments, Anna, Mac Malkawi, Michael Schneider, Oleksii Leonov, Jim Osmun, Tyson McDowell, Ludovic Robillard, Jim buckmaster, fanime96, Ruslan Khroma, Robert Blum, Vincent, Marinus Kuivenhoven, Alfred Wallace, Arjun Chakroborty, Joar Wandborg, Clayton Greenwell, Michael Krugman, Cy 'kkm' K'Nelson,Ron Neal
    Written by Derek Muller and Petr Lebedev
    Animation by Mike Radjabov and Iván Tello
    Filmed by Derek Muller and Emily Zhang
    Footage of the sun by Raquel Nuno
    Edited by Derek Muller
    Additional video supplied by Getty Images
    Music from Epidemic Sound
    Produced by Derek Muller, Petr Lebedev and Emily Zhang

Comments • 68 834

  • Haven DeZeeuw
    Haven DeZeeuw 5 months ago +13669

    I’m so glad this video exists. I use to completely not even understand how electricity worked, and now I still don’t.

    • Troy Allen
      Troy Allen Day ago

      @Paul met Debbie haaaa haaaa... not trying to poke fun I just think the statement is hilarious

    • Troy Allen
      Troy Allen Day ago

      Haaaa haaaa

    • We Share
      We Share 2 days ago

      u will soon, @toor

    • Lance Watson
      Lance Watson 2 days ago

      Lol.....😆😆😆

    • eyescreamcake
      eyescreamcake 3 days ago

      Don't worry; Veritasium doesn't understand it, either.

  • Thomas Cronin
    Thomas Cronin 2 days ago +7

    The engineers at work said the wires are actually filled with smoke, and if something goes wrong, one could accidentally end up letting some of the smoke escape from the wires. They might be right...I've seen it happen.

    • bp4924
      bp4924 2 days ago +2

      Magic smoke. When the smoke escapes, the magic goes away.

  • bp4924
    bp4924 2 days ago +1

    I've always been confused about AC.
    DC was easy because it adhered to the water-hose model.
    Your description of the fields was mind-blowingly simple and easy to understand.
    But I will still treat wires as if the ouch comes from getting in the way of their destiny, and I will blame the positive side for that pain.

  • Issenschaf
    Issenschaf 2 days ago +5

    I come up with an emberassing question: Light is mentioned there to travel in a similar way, with oscillating magnetric and electric fields. If we put a mirror on the moon, to see ourselves in the middle of that and aim with a laser on that center, would we get lasered immediately, as if we directly target it to our eyes, because only that distance matters?

    • ronnie carson
      ronnie carson Day ago

      That's full view in the gleem of 90 feet from couch to ally and beyond. It gives you a head ache if you do it too long until you get good at it

    • ronnie carson
      ronnie carson Day ago

      Gleem of a diamond you should be able to see what in it with your own eye not into the light just the reflection where ever you sit n look into the gleem you should be able to focus down yo the whole picture. I've seen power lines in my gf promise ring I gave her. As a kid, I could see the trees and lines and pole in the gleam thru the back den window from the couch in the living room on the other side of the house

    • ronnie carson
      ronnie carson Day ago

      Yes if it were a diamond mirror no matter the distance you will get a rejection only the right adjustment on the lenses. Will get you an exact picture and reflection would be instant you could focus at the speed of light, say just as that planted came out from behind its sun tto be in view , n you hut that mirror with you lazor , in light years distance , you put out your eye if it's that good a lazor or you maybe removed a floater

    • Michael Carroll
      Michael Carroll Day ago

      There is a mirror on the moon, and they do shoot a laser at it.

    • Louis
      Louis 2 days ago +1

      You wouldn’t. Light travels fast but there’s still a delay. It takes light about 1.3 seconds to cover the distance between the earth and the moon, so twice the amount for a round trip.

  • Bee Dub
    Bee Dub Month ago +79

    This is precisely why a "ticker" or non contact voltage tester works. It will start to blink and tick, slightly before making contact with the wire, even through the wire's jacket or insulation.

    • Jiboo!
      Jiboo! 8 days ago

      @T S im getting my bs in engineering physics and my masters in electrical, also i TA for college level physics 200. Tell me again who is more qualified? Were talking about poynting vectors because the original comment was talking about it.

    • Jiboo!
      Jiboo! 8 days ago

      @Mark II he explains it in the video, electrons hit nuclei and impart some kinetic energy

    • Jiboo!
      Jiboo! 8 days ago

      @T S electric and magnetic flux arent vectors as theyre the dot product of two vectors, making it a scalar. The fields themselves are vectors (im using field here as in the electric and magnetic field vectors)

    • T S
      T S 8 days ago

      @Jiboo! also it isn’t the cross product of two fields. It the cross product of two vectors, one is a field and the other is flux

  • MattMGK
    MattMGK 3 months ago +1567

    After watching this video I can confidently say I understand less about how electricity works than I did before.

    • Alan Beasy
      Alan Beasy 2 days ago

      @Akoola If you are going to comment, at least understand a little about the subject.
      1) there are no electrons “flowing” anywhere between magnetic fields. (Do you think electrons are flowing in light waves too?)
      2) your second comment is just as silly. The water pipe analogy is not explaining how coils work.
      But as you have you mentioned it, you could transfer energy between two water pipes without any water connection if you used a diaphragm and pulsed the water pressure..... not that it would be a very efficient way to do it..... nevertheless, there would be a pressure pulse detected at the end of the second pipe even though no water flowed between the pipes.
      I hope that clears up your misunderstandings.

    • Akoola
      Akoola 2 days ago

      @Alan Beasy 2) The "break" in the continuous line at a transformer is irrelevant because the current in one coil of the transformer generates a current in the other coil so that the energy is passed on the the next set of wires.
      Your argument does not stack up. The current in one coil of the transformer MUST be emitting some form of energy in order to affect the current in the other coil. If electrons are not flowing freely between the two coils, how could one affect the other?
      "So while it is interesting to consider the theoretical concepts involved, practically speaking I can just as easily "explain" the flow of electricity using a water pipe.
      The pump is the generator / the pipes are the wires / the diameter of the pipe is the wire gauge / the pressure of the water is the voltage / the amount of water flowing through the pipe is the current (amps). AC would be a little harder to replicate with water, but the concept can still be comprehended."
      So, according to your argument, if two separate water pipe systems are brought into close proximity with each other, the flow in one pipe will affect the flow in the other? Hmm! I don't think so. Unless, they are generating electromagnetic fields.

    • Puh Chew E. Chomp
      Puh Chew E. Chomp 18 days ago

      @socially unacceptable Oh? That's interesting. Meditate to rid one's self of delusions to see the truth. I've learned something new, thank you.

    • socially unacceptable
      socially unacceptable 18 days ago +1

      @Puh Chew E. Chomp that's some typical zen wisdom there. in buddhism you call those delusions and you're supposed to meditate to rid yourself of them.

    • Monkeysrock
      Monkeysrock 27 days ago +1

      The problem might be because when someone says electricity, most people think its the stuff that turns on devices and what the power company charges you for. Electricity is a field, though, and for the most part people are using the word as a replacement for energy. Which is why the power/energy/electric plant are all the same thing. Try to think of it differently. An electric field is generated perpendicular to a magnetic field, and the orientation of those fields tell you the direction of energy, which is what we pay for and is what turns on our lights. Even a lightbuld is just the little wire in the glass absorbing energy and the super tiny vibrations in the material are heating it up so it can glow.
      This may not help but im not a good science communicator and it gets hard when one field being present almost guarantees the other is too so energy is moving no matter what.
      I guess the fast way to see it is that as long as the fields are present, energy flows, but you need stronger fields for more flow, and we use wires to help maintain the fields. That simplification makes confusions though, so try to just recognize that an electric field is not what the power plant sells, and that energy is not electricity. Electricity is just a way to let energy move.

  • Ingsoc
    Ingsoc Month ago +226

    So a question. If the energy doesn’t really flow and is conducted by fields outside of the wire, how does one get electrocuted by only touching the conductor vs the outer wire sheath, and why does the energy seemingly flow through a person and not around them like a wire?

    • eyescreamcake
      eyescreamcake 3 days ago

      @Mike Static shocks are not negligible current. They have been measured and they go up to ~30 amps. The cliché of "it's not the voltage it's the current that kills you" is wrong. It's the _energy_ that kills you, and static shocks have too little energy to cause any damage.

    • eyescreamcake
      eyescreamcake 3 days ago

      @explorer47422 The definition of "electrocute" is "kill with electricity", so you cannot get electrocuted a minuscule amount. :D You're either dead or not.

    • ub2bn
      ub2bn 4 days ago

      ​@Michaela Jantzen You, and Mr. Veritasium, seem to be suggesting electric fields and magnetic fields (which would have to be "self-existent") must merge to create flow/current. But I thought/was taught magnetic fields are generated by the flow/current. So, which is it?

    • Spencer Kimori
      Spencer Kimori 5 days ago

      @Mike how will u explain why birds of air don’t get electrocuted and actually there r people out there who cannot get electrocuted ?

  • CompuNomad
    CompuNomad Day ago

    Amateur Radio operators know this. I learned this when studying for my license back in the 80's. The truths learned here are the building blocks of antenna propagation theory. Effectively, and antenna works because the energy is forced to leave the electromagnetic field and free float through the air. My answer to the question was actually D because I didn't completely understand E. But my assumption was "instantaneous" has to be the answer because basically it's like a string of marbles in a groove of the same length as the marbles: When you push a marble into one end of the groove, a marble on the other end has to fall off. The marble you pushed into one end did not travel to the other end. It simply created an imbalance that had to be satisfied instantly through the string of marbles effectively affecting only the marble at the other end. However, this current is created instantaneously when the current is applied and it occurs on the surface of the wires and very little "flows" through the wires themselves. This is why stranded wire cable is more conductive than solid wire - because there is more surface area. And I don't say that the electrons move of their own accord... they are pushed/pulled along by the field current. This is how inductance works in a field coil, or otherwise known as a transformer. Similarly electrons move in an antenna through inductance and the wave is forced to leave the antenna through a field being setup where the wave can no longer stay with the wires. In the example of the marbles, your fingers could be called the field/wave current. The marbles can't move of their own accord... you actually forced them to move.

  • Daniel Wehlmann
    Daniel Wehlmann 3 days ago

    Hey Greg, i was showing your video several times and I hope I understand it correctly.
    I've been thinking about what energy really is for more than ten years. Sure, they're electromagnetic waves transported through a magnetic field. In quantum mechanics, we constantly observe that with electrons, photons, bosons arriving and colliding in the detector, there is an associated field that enables this mechanism. I just can't believe the sentence that "electrons travel through a wire". It's more like in copper on a chain, one atom donating its electron to the nearest atom, picking up that electron again, and so on. If the electrons only started running when the switch was operated, it would take 170 years for the electron to travel through the wire and reach the lamp in a 500 km long line. As with Maxwell's equations, it is the field that excites the electrons to a higher state and perhaps only momentum is actually transferred. Since the circuit is already present on the other side, "switch on" only takes half the time you would expect. However, with this "massless impact" the transmission speed is not 300,000 km per second but only about a third, since electromagnetic waves propagate much more slowly in a medium. Perhaps Mr. Maxwell is then even right with his calculations. Light would be transmitted without mass in an absolute vacuum at 310,000 km/s.

  • John Williams
    John Williams 10 hours ago

    I assume this is why clamp meters can measure the flow of energy along a wire without touching it. This includes voltage and amperage. It would have been good if resistance were explained in terms of fields.

  • Dylan Dailey
    Dylan Dailey 6 months ago +4603

    EE here; I think most of this info is technically correct, but potentially misleading in some areas.
    For one, while it's true that energy is transferred in the space around a conductor, as opposed to through the conductor, the *vast* majority of that transfer is taking place *extremely* close to the conductor (we're talking millimeters, typically), due to both the magnetic and electric field strengths decreasing exponentially with distance from the conductor. So in reality, the energy being transferred actually decreases superexponentially with distance from the conductor. Now, in power lines, the ground is still a concern because it's a very long conductor, carrying very high voltage, at very high currents; it's a somewhat extreme case. Yet, even though the cable is *miles* long, we only need to separate it from the ground by tens of meters to significantly reduce losses over that long distance. Furthermore, the ground is only a problem because power lines are AC. If they were DC, you could lay the cable right on the ground, and you wouldn't get any significant energy loss.
    Edit: see below, the dropoff is not actually superexponential, but the general idea that energy transfer is greater closer to the conductor is still accurate.
    For two, the analogy of electron flow being like water through a tube is actually still accurate in the case of the undersea transmission line. The metal rings around the cable cause a change in electrical impedance for that section of the cable. In the case of water in a tube, this would be analogous to having an air bubble trapped in your tube. As a pressure wave travels through the water, it will suddenly hit this air pocket, which is far more compressible than the water (i.e. has a different impedance), which will cause the waveform to distort in precisely the same manner as the electric wave does in the cable. Some energy will pass through the bubble, creating your distorted (attenuated) waveform, and the rest of the energy will actually become a wave reflected back in the other direction. This is precisely what's causing the distortions in the undersea transmission line. There's a bunch of reflected waves bounding back and forth between all the iron rings that stretch and distort the original signal. (for the real electrical nerds, check out "time domain reflectometry", which uses this principle to precisely detect where a fault exists on a power line)
    Third; yes, energy transfer from the switch to the bulb will occur in 1/c time (by the way, I think you could clarify this by representing it as d/c time, where d is distance from the switch to the bulb. You never really state where the 1 comes from in that equation (at first I thought you were implying it was a constant value, unrelated to this distance)). And yes, you do clarify that it will only be a fraction of the steady state energy. But I think you should stress that this would be an *extremely* small portion of that steady state energy. The initial energy that the bulb receives will only be due to the capacitive and magnetic coupling between the two long portions of the conductor. And in the case of wire separated by 1 meter, both the capacitive and magnetic coupling would be practically zero. This again is due in part to the exponentially decaying electrical and magnetic field strengths with distance from the conductor, as well as the poor electric and magnetic permiativity of the dielectric (air) between the conductors.
    Fourth; addressing your question about "why is energy transferred during one half cycle, but not returned back to the plant in the other half of the cycle", I think your physical demonstration actually explains that perfectly. No matter which end of the chain you pull, there's something down the line offering resistance to the motion of the chain. Heck, you even get friction between the chain and the tube, which is like resistance in electrical conductors. However, if you attached a sort of clock spring to your wheel (such that the spring always worked to return the wheel to its at-rest position), you would indeed see some energy returned to the power plant (you) on the second half of the cycle. This is analogous to powering a capacitive load with AC.

    • Commenter Of Truth
      Commenter Of Truth 14 days ago

      it just sounds like you gave more information on what he already said, to clarify or slightly adjust into a more detailed format. if its misleading to anyone, I understand that part. but they should dive a bit deeper in understanding anyways lol. so the misleading aspect is autosolved by human intuition. except, a lot of people seem to lack that.

    • Bangkit
      Bangkit Month ago

      Thank you, its much easier to understand!

    • Eddie C. - The Raven
      Eddie C. - The Raven  Month ago

      Just some misleading areas :) You have a much more eloquent way of calling bs than I do

    • Merilix2
      Merilix2 Month ago

      @Sorin Craciun In fact, the answer 1/c doesn't make any sense at all because 1/c is not a unit of time. 1/c is just a constant one can use to translate between time and length units but is neither of both by itself. Unit calculation is somewhat basic physics I'd say.

    • Medi
      Medi 2 months ago

      My god, the video was pretty misleading and at times downright incorrect, and now we have another not-so-correct comment by @Dylan Daily who confuses the hell out of people. In short, no, the answer is NOT 1/c, "for all practical purposes". The energy must travel along the wires to get to the bulb, again for all practical purposes. Many have explained in the comments, so I won't do it again.

  • Lore M
    Lore M 27 days ago +10

    I LOVED this and you explained it so well, I thank you so much.
    In 2017 I was privileged to visit several museums in Glasgow, Scotland and learned a lot about Kelvin (whom I’d never heard of) and saw several of his inventions. I was fascinated by his first tide machine…
    One of the things that I appreciated in your presentation here, is the different theories purported in trying to understand the flow of electricity. It reminds me of Isaiah 40:26 where it speaks of the creator is full of dynamic energy…so hearing and seeing your explanation here (thus putting to rest my erroneous belief that the energy just followed the wire…) makes me appreciate its creator even more. To me, logic demands that these complex and unfailing laws have been designed. I’m certain that there are even more refinements in understanding (in all scientific fields) are yet on the horizon. Thanks for making learning these things so interesting and fun (for me) I appreciate being your student, now. 👏👏👏

  • docbrown237
    docbrown237 Month ago +14

    At last!! I had a high school teacher 54 years ago (Dr. Schoenfeld) that beat your electrical pressure/EM field transfer of 'electricity' through a circuit in our heads. Later, I recall on a test in college Physics 110 where the correct (or accepted) answer was always ' ...by virtue of the flow of electrons through a conductor'. I always wondered how many of us students took a fraction of a loss in our GPA due to this belief. Excellent video explaining how capacitance (or inductance) play a role in something most everyone takes for granted. More I²R to you!

  • Steven Lightfoot
    Steven Lightfoot Month ago +27

    You have blown my mind. I am a Mech Eng, and have never heard of the Poynting Vector, but have been struggling to understand power flow direction for at least five years. I think this will lead me to the answer.

  • Robert Ritchie
    Robert Ritchie Day ago

    The most important part of this video in my opinion starts at 6:00 and continues for 15 seconds. Proof that the electric and magnetic fields are separate entities. Thumbs up a very educational video and I agree with the content 100%.

  • Randall Parker
    Randall Parker 6 months ago +650

    I'm 66 years old. As a child, we lived near large transmission lines in a rural area of CA. They passed over one of our pastures. We had a small water pump shed near the base of one of the towers. I "helped" my dad bury the power wires to the pump shed, 400 ft. from our barn/shop when he was installing a new pump. My dad used pipe strapping tape to mount some fluorescent tubes inside and outside of the shed. Everynight the lights were always on and I asked him why. He took me out to the shed, and asked me if I felt anyything... I realized that the hairs on my arms felt tingly, and I felt something in my ears. He explained about how such high voltage cables as above "induce" a magnetic field way around the big cables, that's what gives me the feelings, and what makes the tubes glow like they were wired to something. That had to have been 1960 /61- as I had just started 1st grade. He drew some sketches to show how "he thought" it worked. He gave me a basic electricity book and quizzed me every once in awhile. His sketches looked just like your graphics. I guess my dad WAS a lot smarter when I was younger. LOL

    • m s
      m s 8 days ago

      @MarkoZBogdańca The tube itself is the 'loop'

    • makrisj
      makrisj 26 days ago

      @Daniel Kohwalter In my place there was some1 that coupled many turns on a fence to the neighboring AM antenna. They tuned the loop with variable capacitors and they led the power via a T-match to the heating element of the boiler, having hot water during the winter.
      Up to the moment measurements revealed that the lobe of the antenna has changed radically. All sides of the antenna interact to create directivity, thanks to the conservation of energy. So if you "steal" some of the energy the antenna lobe goes on a different direction.
      Engineers went into the problem, took ferrite loops around the antenna field, found the... "leak", fined the culpit.

    • makrisj
      makrisj 26 days ago

      @graham121150 electrons are being ripped apart from the mercury atom (the vapor inside the tube) and then recombine with another neighboring ion to reform the mercury atom. The electron that recombines with the atom loses energy in the form of UV photon. That photon interacts with the phosphor on the glass of the tube (the white stuff). Visible light is being emitted.
      It could either have an E-field between the ends of the tube, or an E-field between any points in the space surrounding it - if the field is strong enough, electrons could be ripped, recombined, the fluorescent tube will glow.

    • makrisj
      makrisj 26 days ago

      @MarkoZBogdańca If there were high voltage lines, then they had to be AC. Maxwell goes: If your E field across a conductor is changing over time, there is magnetic coupling that induces *reverse phase* voltages to that conductor's edges or surfaces.

  • PersonwithaName
    PersonwithaName 14 hours ago

    If one was able to dampen the electromagnetic waves from traveling around a power line, would that thus mean no electrical current would be transferred? I mean if you could shield the cable somehow from allowing these waves from extending outside of the cable itself.

  • James R. Arnold
    James R. Arnold Day ago

    I'm sure this question has already been asked: So how does energy flow if the wire is insulated?

  • David Simpson
    David Simpson Day ago

    I will guess: E. I'm guessing that the EMF (electro magnetic force already in the wire is like water in a pipe. When you turn on the water, you get what is already in the pipe. So as soon a current is introduced (which is a positive attraction, suction/vacuum so to speak), the draw of electron's EMF is immediate. That's my guess.

  • Toujours L'Amour

    WOW!! That is fascinating. I have an Electronics Engineering degree and they NEVER taught this in school. This is AMAZING!

  • Mr. Jason
    Mr. Jason 6 months ago +554

    This actually raises more questions than it answers.

    • Fullson Chuang
      Fullson Chuang 2 months ago

      @noise5555 1/c is time, not velocity

    • gordo teton
      gordo teton 2 months ago +1

      welcome to actual science

    • Q Revere
      Q Revere 5 months ago

      @Jaden Prayers for blessings of wisdom and good fortune.

    • Jaden
      Jaden 5 months ago

      @Q Revere such big words yet you can't seem to find the period button. Here copy and paste mine ".".

    • Q Revere
      Q Revere 5 months ago

      @Marko Topolnik This would make much more sense, while also making many much more angry, if you incorporated dielectricity into your model.

  • Randy Liu
    Randy Liu 22 days ago +2

    I've been actually thinking about this for some time already. Thanks for the video, although I still don't get some idea
    1. 7"15, the current inside the wires create magnetic field outside the wires -- Shouldn't magnetic field created only when "current changes direction"?
    2. 6"18, when circuit is connected, its electric field extends through the circuit at the speed of light -- How (why) does the electric field spread through circuit? And the speed of light is the light speed in air or in wires (although I don't know how to define speed of light in non transparent object)
    3. 6"31, (electrons) depleted elsewhere -- How is "deplete" defined?
    4. 7"00, the charge on the surface of the conductors also creates an electric field outside the wires -- So which electric field combined with the magnetic field (created by the electron movement -- my 1st question) delivers energy? The electric field from battery that makes electron to start moving? Or the electric field created by the surface charge of conductors?
    5. 8"13, the energy flow is a space integration of the complete circuit, include power source, power drain and conductor, if I understand this part correctly; then the question is, if power source and drain are next to each other, but conductor spread out a long way (1 light second, as your imaginary experiment), the energy flow "along the conductor" only reaches power drain gradually (behind the energy from source "jump to drain", because they are next to each other), so the power drain receives full energy 1 sec later?

  • Fr34k 0.o
    Fr34k 0.o Month ago +8

    Love watching Your videos about mathematics and physics. A real good source of information and study for independent research :)

  • Scott Horton
    Scott Horton Month ago +34

    So if we consider that the wires are really just antennas that allow the EMF's to be focused and contained, we begin to understand why Tesla believed he could transmit power wirelessly.

    • chistine lane
      chistine lane 25 days ago

      What do you guys all think radio is?

    • operatorblack
      operatorblack Month ago

      This is exactly where my brain when when I started processing this video

    • Stephen Church
      Stephen Church Month ago +15

      Tesla knew it could be done when he proposed it because Maxwell had proven the math and Crooks and Lodge had proven it experimentally. This isn't meant to diminish the genius of tesla because he absolutely was a genius inventor but it's important to understand scientific discovery and innovation as a constant building on the work of predecessors.

    • Johnmichael Quinlan
      Johnmichael Quinlan Month ago +6

      he didn't just believe it he proved it at the Royal Academy in a live lecture. They recently repeated the exact experiment you can find it on their youtube page.

  • Jens Schiønning Larsen

    Oh great I got a D - in my high school Physics exam back in 1997, for explaining that the way electricity is being described in the school books are wrong and it was more like what you described it to be.
    Glad to know I could have been an engineer If I had gotten that A in Physics.

  • AT
    AT Month ago +812

    The fundamental law of physics: electricity disappear if you stop paying bills.

  • Perry Nally
    Perry Nally Day ago

    This makes a lot of sense. But if the energy is actually being transferred through the magnetic fields then why doesn't a lightbulb light up that is near the original bulb but not touching the lines? There has to be electrical contact with the current, correct? Or does there?

  • David W
    David W Month ago +3

    This is great info. I learned electron theory in the 70's USN electronics program. Of course, we've learned more between then and now than we had up to that time. I did question using the term "lie" for what we learned. I'd think it was taching to the best we knew, or maybe to the level a non-physicist could grasp... was isa "lie"?

  • Redietu Haile
    Redietu Haile 5 days ago

    @veritasium, what would the vectors look like if you’re using a light bulb near a Tesla coil? The bulb turns on when it’s not touching and the sparks generated by the coil are reduced/muted and I can’t figure out which direction the energy fields are going or what the cross product looks like.
    If anyone can help me out, it’d be greatly appreciated!

  • Daniel
    Daniel 24 days ago +3

    There’s a great book called “There Are No Electrons” by Kenn Amdahl that explains these concepts and more in hilarious and intriguing ways.
    If there’s one thing you can take from this, it’s that electricity is not electrons moving like water through a pipe.

  • giovannipu
    giovannipu 6 months ago +378

    Hello Derek, a physics professor here. I love your videos and I subscribe to your channel - in all honestly, I consider it the best example of public communication of physics and science I have ever met - I am not exaggerating. I actually used some of your videos when teaching to my students. However, you did not convince me with this one - not that I love you any less for this. I have similar objections to some that have been made by others here. The explanations of the fields, and the Poynting vector are gorgeous and very instructive, by the way. But I have tried to explicitly calculate the flux of the Poynting vector on the bulb, and I find it to be quantitatively a small effect (quickly dropping with distance of the bulb). Yes, there is *some* disturbance at the bulb, but I think it is a bit misleading to just say that it "turns on". I suggest to have this checked by other people - I would be very curious to see a follow-up on this. You are actually tempting me to try this out in my own lab.
    Anyway, even if it turned out you had slipped on this one, that does not change my opinion about your work. Physics is non-trivial, and what really matters is to have the right scientific approach to problems, not to never ever make a mistake (even Galileo did) - eventually things sort themselves out if you follow the right track.

    • Ted Rees
      Ted Rees 2 months ago

      @giovannipu But the initial current will not reach the bulb until the voltage at the bulb rises due after the transmission time delay.

    • Ted Rees
      Ted Rees 2 months ago

      @SpeedFlap All wire has inductance and capacitance. They are both finite element models for the em fields.

    • Ted Rees
      Ted Rees 2 months ago

      This video is misleading. Just because the Poynting vector points in the direction of energy flow, it doesn't mean that it causes the energy flow. The conclusion is also dead wrong. Anyone working in a lab with a fast scope can observe the time it takes for a signal to flow down a wire. You don't need a stupid impossible single wire 2 light seconds long. All you need is a few feet of wire on a bench, and a signal generator with a fast pulse generator. Sync the scope from the generator, and probe along the wire. you will see that the pulse is delayed a bit more than 1 nano second per foot. Putting the end of the wire next to the signal generator doesn't make the time delay go towards zero.
      By the way, for fast signals, the wire should be a transmission line, that consists of another return line spaced closely to the signal line, that is grounded. It could be a twin pair, or a twisted pair, or a coax with carefully crafted test points. The load should be a resistance equal to the characteristic impedance of the transmission line. Otherwise, you get the signal bouncing from the end of the line and traveling back to the generator.

    • Ersin Emre
      Ersin Emre 4 months ago

      Professor all your calculations are inaccurate because of we don't know how fast the space is expanding. He is good in this video because İ always thought what the hell a lot electrons coming from.

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      Amani 4 months ago

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  • Duke Of Hesse
    Duke Of Hesse Month ago +2

    I got as far as James Clerk Maxwell. From then on I found my mind wondering more about how I was going to cook a cheeseburger, grill or seared in a pan. But I liked the chain in the plastic tube part. That was pretty clear even if it is wrong.

  • Ric P
    Ric P 25 days ago +5

    hey, what are good books you would recommend for a novice trying to learn about electricity the 'correct' way? - Thanks for the great video

  • MFM
    MFM 25 days ago +4

    i would say yes, because i have seen multiple arcs from powerlines over the years from when people get too close with construction vehicles. the higher the voltage, the higher the wire, because you need it to be farther away, as the field is larger.

  • David Yancey
    David Yancey 16 days ago

    Yes! I see the light!!! Wonderful subject, well demonstrated, and doesn't it feel like this has some even more profound realizations down the road. Thanks.

  • John Chessant
    John Chessant 6 months ago +522

    The part about AC was mindblowing. The Poynting vector is S = E x B but if both E and B are reversed, then S = (-E) x (-B) so the energy flow stays the same!

    • Michael Smith
      Michael Smith 6 months ago +1

      Well as far out towards infinity as it can get… you can’t really have an instantaneous voltage rise, but you can get close.

    • Vlog City
      Vlog City 6 months ago +1

      @sumilidero yes that is true!
      but by their own rules and logic if the resistance of the source is higher than the resistance it should circulate in the secondary circuit if a path is available

    • Daniel Douglas
      Daniel Douglas 6 months ago +1

      @sumilidero We have both. C being mainly what turns on the bulb, plus the series and mutual L of the wire (with negligable coupling coef.) over the 1 meter gap.

    • AlwaysDisPutin
      AlwaysDisPutin 6 months ago +1

      @Eric Dugal lol It literally says S = E x B but

    • sumilidero
      sumilidero 6 months ago +1

      Until you have L or C component that can store energy. Then it pumps it back to the source at the part of the cycle, aka 'reactive power'

  • Patricia Duncan
    Patricia Duncan 25 days ago +5

    There was a leap in education between my A Levels in the 60s and the OU degree I did much later. As a teacher, I taught the field concept. I totally agree with your explanation. I love Physics.

  • Tim Appleby
    Tim Appleby Month ago +1

    If electricity didn't work this way, how would EMPs be effective at knocking out a grid? Seems reasonable to me that if the electromagnetism in closed end circuits opposite the energy delivery systems suddenly lost their energy, it wouldn't be able to be easily replenished.

  • Peter
    Peter 21 day ago +1

    I know that when they installed the transatlantic cable they had to splice the cables a number of times, but why didn't they test it on land before dropping it? I assumed the conductive water was what caused the interference, not the iron sheath.

  • Dexter Lakeriver
    Dexter Lakeriver Month ago +2

    I my electrodynamic class we used this poynting vector as well, but for electrical application (unless RF applications) most problems can be solved by considereing each wire as an resistor, inductor and capacitor at the same time. Many people knows about the RF cables for television, The shielded ones, they are used in a what called "75 Ohm System" in which the properies are well defined, and it is much easier to use this concept instead of using poynting vector directly, of course they easy considereation can be derived from the poynting vector. The electron is moving picture which is shown heare is a little bit missleading in terms of that the electron have to travel from the source to the bulb. It is more like you have a all electrons in place only kick one after another until the pulse is reaching the bulb plus the velocity of the electrons itselfs. And yes moving charges creates mag. fields, which is a major damping faktor of the initial pulse. The phenomena is called inductance. So it is not something new or changing to use the poynting vector directly to calculate the energy transfer it can sometimes be convinient to use it. Unless you don't have to do something with RF applications use the electron as electrical energy carrier and ohm's law. have a good one :)

  • number 33
    number 33 6 months ago +128

    It's pretty easy to test this. Just take a 100m length of 50 Ohm coax cable arranged in a big loop with the ends 1m apart, connect a 50 Ohm pulse generator to one end and a 50 Ohm resistor across the other end. Use an oscilloscope with two matched probes to see how long it takes for the voltage to arrive at the resistor. If it makes you happier you can put an LED in series with the resistor and cal it a light bulb. The result will be about 0.5 microseconds and not 3 nanoseconds.
    Of course I know I'm talking to myself, there's no way Veritasium can read 30,000 comments.

    • Aditya
      Aditya 22 days ago

      Derek probably did read your comment

    • George Hnatiuk
      George Hnatiuk 6 months ago

      @Coco Sloan time = distance/c so yes, 1 second = 300 000km/(300 000km/sec)

    • Coco Sloan
      Coco Sloan 6 months ago

      @George Hnatiuk So if the distance between battery and lightbulb is 300 000 km only than it would take 1s for the lightbulb to shine ? Is your ping lower near your router ? Check it !

    • George Hnatiuk
      George Hnatiuk 6 months ago

      @Coco Sloan that is not what is going on here. There is no faster than light energy transfer occurring or suggested. Veritasium is claiming that the primary path for energy transfer is not along the 300 000km wire but in the 1 meter air gap from the battery to the bulb. Yes there is a slight coupling there but it is INSIGNIFICANT for the dominant transfer of energy occurs much later in time than 1m/c along the wires.

    • Coco Sloan
      Coco Sloan 6 months ago

      But OFC he's wrong. Its a comment-bait Sir . He's example suggest that distance of 300 000 km can be crossed over faster than light . Why ? Because the electromagnetic field is already there ? So there's something faster than light ? Yeah right . Only stupid thought is faster than light !

  • ray Nic
    ray Nic Month ago +10

    I always assumed it was more like a Newtons cradle type of thing. I mean one electron stimulates the next, it does really get displaced and run the distance. Waves in the ocean move similarly. A wave travelling at 20 mph isn't moving all the particles in the wave at 20 mph. The particles are barely moving, but the energy pushing one particle into another keeps the wave moving. With the exception of a breaking wave or when they run out of resistance at the beach and run up.

    • eb bay
      eb bay 13 days ago

      exactly correct its not the flow but the movement that gives the power

    • Amos Backstrom
      Amos Backstrom Month ago +1

      You're still basically right. However a small amount of energy is transmitted through the air at the speed of light. The switch is so close to the bulb so it "receives" this energy first (picks it up like an antenna). This amount of energy is negligible and would be practically undetectable, nevermind being able to light a bulb with it!
      What Veritasium did here is very misleading in my opinion. While he did a good job explaining certain aspects of the science, overall he's cherry picking variables to push a narrative, which leads to misunderstanding.

  • Richard Mathews
    Richard Mathews Month ago +5

    This reminds me of a problem on transmission lines posed by one of my physics professors. I’m not sure which one, but I think it was Richard Feynman. It was expressed differently, but I think it comes down to the same thing.
    To make my point even stronger, I’m going to make the lines be half a lightyear long instead of a light-second. The battery is big enough to provide power for years.
    The video is absolutely correct about energy flow being dictated by E × B, but the conclusion that the light bulb immediately lights up is wrong. The short explanation is that for a year the circuit is equivalent to having thousands of ohms of resistance in series with the bulb. With any realistic combination of battery and bulb, that will not allow enough current to light the bulb.
    The sets of wires act as two transmission lines running to each side. When the switch is first closed, almost all of the energy flow will be along each transmission line. The wavefront of that energy will move at almost the speed of light. There will be almost no energy flowing through the bulb. We can determine this quantitatively as follows.
    Each transmission line has a characteristic impedance determined by the ratio of the thickness of the conductors to the distance between them. With conductors that are 1 mm thick and separated by 1 m, this is an impedance on the order of around 1000 Ω.
    For the first six months, energy flows down the two transmission lines. How the lines are terminated doesn’t matter during that period. Until the wavefront reaches the end of the line, it might as well be an infinite transmission line. If there is a matching resistor at the end, it acts like an infinite transmission line forever. An infinite transmission line acts exactly the same as if it were replaced by just a resistor. The energy flowing into the transmission line is exactly the same amount of energy as the equivalent resistor would turn into heat. The circuit is equivalent to having a battery, a bulb, and two 1000 Ω resistors in series. There is no light with so much resistance.
    If the lines are terminated with a short (which is what this video posits) or an open, there will be a reflection wave that will take another six months to reach the bulb. If there is an open, B in the reflection wave cancels B in the original wave; so E × B is zero, producing no light. If there is a short, current will flow, B will be non-zero, and the bulb will illuminate a year after closing the switch (the reflections will actually go back and forth for a while, so it may actually take several years to reach a steady state).
    How do we know this? Once the round-trip transmission delay passes, the length of the transmission line is irrelevant (neglecting resistive losses). It will behave exactly the same as it would if the short or open were at the end of a light-second transmission line or a one-meter transmission line, and we know what happens in the latter case from experience.
    During the round-trip transmission delay-something like 2000 Ω of serial resistance and no light. After the transmission delay, negligible serial resistance thus giving light.
    Here is a final though experiment that maybe makes the importance of the transmission line clear. What happens if you place the switch at the end of the line, half a lightyear from the bulb? Can closing the switch instantly make the lightbulb light up? What does E × B look like before and after you close the switch?

  • Robert Martinez
    Robert Martinez 4 days ago

    Resistance can literally be measured and electrons in an ac circuit don’t move back and forth where they stand. They bounce off the next valence electron knocking that electron to the next atom. This happens full circle in one direct then back in full circle the opposite direction. The electrons are being pushed with a magnet spinning in a the center of a coil of wires. When the North Pole of the magnet is at its peak at any given point it is pushing the electrons in that wire in one direction and the opposite by the South Pole of the magnet. This can also be measured. And you can use a sine wave to prove this. Yes this also creates a magnetic field in the wire but the electrons are producing energy, the same energy is creating the magnetic field. But the electrons in low resistance create heat as through the filament of a light bulb. That filament has low resistance so the electrons need to fight hard to pass creating high energy and heat which then create the filament to get hot and glow creating the light. Also you said that the metal from the underwater sea cable distorted the magnetic field however we use emt and other metals as conduits and it does not create distortion.

  • Junk Mail
    Junk Mail Month ago +1

    Electroboom, I'm a retired electrical engineer. I love your video. I wanted to say, importantly, the word is impedance NOT impotence!!! Yours is the third of three videos I've watched on this. First was Veritasiums, then Dave at EEVblog, then yours. Dave said that we engineers think about things differently. That we have tools to analyze things and validly track physics and the rules of science. You fellows have collectively reminded me of much of the complexity we were trained to understand and analyze and calculate. I've much forgotten what I was trained and educated to deal with. I've been so browbeaten by the mindless politics and public chaos of people and the media news etc. I've forgotten the promises of my youth and education. RU-clip, multimedia and Internet is a terrible way to waste a capable mind. You've helped to retrieve my past capabilities. Thank you. Amind is a terrible thing to waste, and you've given me a wake-up call.

  • Matteo L.
    Matteo L. 6 months ago +241

    I think one of the most difficult things about the Poynting vector is to visualise the cross product in your mind. That video with all fields represented in space is extremely helpful and should be shown in EM courses.

    • Ferretcatcher
      Ferretcatcher 6 months ago

      Poynting vector is a redundant term; all physicists know that vectors point!

    • Alex Maltais
      Alex Maltais 6 months ago +2

      I don't think this video is appropriate for a university course.

    • Randy Pittman
      Randy Pittman 6 months ago +1

      Once again I remember why I nearly failed E&M in college.

    • Eugene Bird
      Eugene Bird 6 months ago +4

      The vector isn’t a real thing, it’s just a mathematical device.

    • marvinalbert
      marvinalbert 6 months ago +1

      @Isaac Groen Actually arrow directions are pretty wrong, they're much more parallel to the wires.

  • sickleandsuckle
    sickleandsuckle 13 days ago

    I remember learning about the Poynting vector in undergrad but never knew its significance. Now I do!

  • Matteo Cucchi
    Matteo Cucchi Month ago +1

    Great video, thanks. However, something is not in line with my intuition. Yes, electromagnetic energy gets to the bulb from the battery in no time. But is this energy that is lighting up the bulb? How does the resistance of the wire, the actual motion of electrons, and the voltage drop get into the picture?
    For example, some devices (LEDs, transistors..) would need a voltage to work, rather than electron flow. Does this electromagnetic energy make them work without "knowing" what's on the wire? i.e. its resistance.
    Moreover, if one assumes no resistance of the wire, we are assuming infinitely high electrical mobility, which reflects on infinitely high drift velocity of the electrons, and not a fraction of millimeter as stated in the video.
    On the contrary, if one assumes finite mobility, also the resistance is finite, and will be very large for such a long cable...and electrons will move very slowly and the light bulb will hardly turn on.
    Not sure I am raising good points, but i can't generalize the lesson of the video to other examples.

  • Waldemar kamiński
    Waldemar kamiński 22 days ago +1

    Very funny!
    The drift speed of the electron is known to be 1/10mm/second. In the example: An electron "leaving" a battery 100m away will reach us after 28 hours. So, even if it "pushes" other electrons in the wire/cable. And there would be "friction" in the filament of the bulb would still not heat up and would not light up.
    This is knowledge from primary and secondary school that the current flows and it is not.

  • Artifactsofmars
    Artifactsofmars 2 days ago

    OK I will break this down for you. First off, the reason that A/C is used for long distances is that D/C suffers too much in the way of I^2*R losses (current times the resistance squared) to be effective. So it is transmitted over long distances using A/C. The energy is conserved because of a force called counter electro motive force in the generator. Along the way of transmission, there are still I^2*R losses (due to heat), and every time there is an energy conversion, some power is lost.
    This makes wind and solar GROSSLY inefficient, as they produce D/C electricity that has to go through inversion (changed to A/C) and then the electricity goes through step-up transformers for transmission through the high tension lines. That does not apply to hydroelectric.
    Most household gadgets actually put the household current into rectification, or conversion into DC for internal use. Your original example would not work because D/C current as I said does not flow very well over long distances.

  • Backlash
    Backlash 3 months ago +588

    WOW! I'm 80 years old. Started learning electronics in the Army in 1959. We were taught the "Right Hand Rule" in the study of inductors and transformers. Although we knew about the magnetic field around conductors we never applied that knowledge like this. Thank you for teaching an old man a new trick.

    • Backlash
      Backlash 2 months ago +2

      @Matt Donahue Exactly! That poor elephant.

    • Matt Donahue
      Matt Donahue 2 months ago

      @Backlash you must mean being "westinghoused"?

  • Samuel Schneider
    Samuel Schneider Month ago +6

    So in theory you could disrupt, strengthen or average this energy transfer by influencing this magnetic flux? Would this be similar to the application of the ferrite bead you see on charging cables?

    • John Hunter
      John Hunter Month ago

      thanks for letting me know what that ferrite bead is for and what it is called. I always wondered and now I know!

  • Jorge Almeida
    Jorge Almeida 7 days ago

    I have a question... if the bulb would take 1/c seconds to light up, then the magnetic field would be traveling from the batery to the bulb faster than light wouldn't it? is that even possible?

  • Paul Capri
    Paul Capri Month ago

    Very interesting and also difficult for this layperson to understand. I think part of what makes it hard to understand is the fact that we do not experience an 'electric shock' outside of the wire but only when e come in contact with the wire itself. I suspect the explanation of this will involve Amperage.

  • Octopus Ears
    Octopus Ears 3 days ago

    I can literally feel my brain working overtime watching these videos

  • Lone Kanne-Hansen
    Lone Kanne-Hansen 6 months ago +695

    "Now that you understand how electrical energy flows..."
    Bold assumption, sir! I'm still wrapping my head around this lol

    • foxopossum
      foxopossum 2 months ago

      Lol same. I feel like I need to watch again but take notes 📝

    • Terry Plank
      Terry Plank 3 months ago

      @Neo the Riot Your not stupid he is selling BS wrapped in facts

    • Colin Brown
      Colin Brown 3 months ago

      Thats cause its deceptive

    • Michael H
      Michael H 5 months ago

      It’s interesting but useless to me. Shame really, I want to understand, then remind myself it actually doesn’t matter if I do or don’t.

    • Lukas Wögerbauer
      Lukas Wögerbauer 6 months ago

      @Neo the Riot
      Think of the electromagnetic field as a very narrow tube around the wire. Only with very high voltage this electromagnetic field will become strong enough that you have to keep a physical distance from the wire. The field is not as strong or wide as shown in the sketch.

  • Davids Gaisevskis
    Davids Gaisevskis 29 days ago

    Two questions
    1) if the wires were a lightyear long, would the light come on immediately too as opposed to one year of waiting?
    2) if the electric meter was placed one light year away, how much of electricity consumption would it register?

    • Fattah Pras
      Fattah Pras 28 days ago

      watch his newest video for answer

  • Cly Roth
    Cly Roth 18 days ago +3

    As this vid explains (without saying the words), the photon is the force carrier particle for electromagnetism, not the electron. All electric and magnetic interactions (energy exchanges) are transferred by photons split off from electrons dropping to lower energy levels. Invisible Mr. Spock just told me so.

    • Rob Cairney
      Rob Cairney 17 days ago

      And it is only at that (quantum) level that it really makes sense. In this explanantory video there is a lot of assumed information such as ' impedance' that we all naturally assume is something that impedes the flow, but does it really? It's all a bit like the innaccuracies taught to trades people so they can do their jobs, without having to grapple with significant real and complex knowledge. Anyway, the full quantum level explanation requires a lot of assumptions as well, because it just does not add up in the classical macro world we have evolved to understand.

  • heavyhappylove Burger
    heavyhappylove Burger Month ago +2

    I only have electrical theory up until N3. Electronics n2. I am 46yrs of age and let me tell you something...you guys are all brilliant and it is so exciting to be able to learn through a medium like today. I would have never BELIEVED in 1998 that the present DAY, through mankinds advancements in tech was REAL. Thxfull for all the engineers for all their hard work in making earth incredibly exciting. i have depression and every time i see things like today even though sometime i get hacked, and stil it gives me hope for a chance on a future. @@@@@This also my my first sincere comment of 2022. @@@@

  • Rizzit
    Rizzit 3 days ago

    So I'm a go with E) as my first impulse stopping at 0:37 seconds. first of all copper has resistance and the impact of impurity for 300k km wiring will have a huge draw. Second, I'm unsure but I think electricity bounces on the inside of the conducting material a bit like light does inside of fiberlines in telecom, the insulation around the copper is just there to force one of two directions. thats my general understanding i'm stoked to see the answer

    • Rizzit
      Rizzit 3 days ago

      0:43 lol...

  • Sam Gralla
    Sam Gralla 6 months ago +249

    It's great to see the Poynting flow argument reaching such a large audience! I always cover this in my college E&M classes. But I have to say that the claim that the light bulb turns on right away is pretty misleading. Consider the case where the circuit is actually open -- somebody cut the wire 300km away. By causality, the light bulb's behavior is identical in both cases (closed and open circuit) for t

    • Lady Mercy
      Lady Mercy 6 months ago +1

      Yes.
      The wavefront intersect the light-bulb almost instantly. But the wavefront carries 0 energy, because the energy is the integral of power with respect to time. Their thought experiment only functions in this way in the specific instance when the amount of light being emitted is "none." And if they did integrate across time, then they'd have to contend with destructive interference coming in from the other side of the circuit. It becomes a problem of "how long does it take to build a square wave that resembles a DC current?" That number is obviously proportional to the length of the wire, regardless of what Poynting's hand mnemonic suggests. His mnemonic for helping him to remember which part of his body is on which side only indicates angle through space, not duration through time. It's an inappropriate usage of the information it was meant to convey. Bad science all around.
      But honestly, I'm just stoked that they decided to make a video pointing out the flaws of the fluid-through-pipes analogy that misconstrues electrical transient phenomena. That's a step forward, by my estimation

    • Urano
      Urano 6 months ago

      @GimpIsNuts dude I'm so glad you made this comment because I didn't catch that at the start of the video. I went back and it's at 12:30 where he reiterates what I said. So thank you.

    • Daniel Gould
      Daniel Gould 6 months ago +1

      This video is pure nonsense. All you have done with the Poynting vector fields is replaced one question (1) with another equivalent question (2):
      1. How long does it take for electrons to start moving through the light bulb?
      2. How long does it take for the Poynting field to "reach" the light bulb (in the sense that the integral of the Poynting field through a small bounding surface S around the light bulb, is nonzero)?
      Clearly, (2) depends on (1). If there are no electrons running through the light bulb, then there is constant magnetic field around the lightbulb and therefore the integral of the Poynting field across a surface S around the light bulb is zero, and the energy transfer rate is zero.
      You fallaciously assume that the Poynting field from battery to lightbulb can be established at the speed of light, which is why you reach the false conclusion that the light bulb turns on after a time of 1m/c. I also wonder if you are fallaciously thinking that the Poynting field transports energy at a "speed" of c? If you think about it, there is no such thing. There is just a rate of energy flow; it makes no sense to ask how fast it is moving unless you can identify a particular chunk of energy and see how long it takes move from A to B. But you can't do that.
      To get the correct answer, you need to apply your own logic from earlier in the video: the electric field within the wire can propagate around the circuit at a speed of at most c. Until there is an electric field across the bulb, there are no electrons flowing through it, the integral of the Poynting field is zero, and therefore energy transfer rate is zero.
      So the correct answer is "at least 1 second".

    • WeBeGood
      WeBeGood 6 months ago

      This is my take on it, really like your comment about someone cutting the wire 300km away.
      The energy may be flowing only 1 meter, but it took 300,000,000 meters for the E/M field to be established in the wires leading into and out of the light bulb. There is no E/M field in wires connected to the light. I'm using shielded wires so that the two long parallel wires don't create any electromagnetic interference with each other causing them to behave like a transformer

    • Colruyt Gaming
      Colruyt Gaming 6 months ago

      ye I was already questioning because of the part where he says the electrons move a bit , if it was supposedly turned on the reaction of electrons 300.000 km away moving a little bit should have happened faster than the speed of light which would break the law of physics

  • terrell lewis
    terrell lewis Month ago +6

    I was an EE and understand the flow of electricity through wires and circuts. This illustration is the best explanation I've seen. Thanks.

    • brian g.
      brian g. 27 days ago

      I have a good basic understanding as a telephone tech testing lines I was trained by an old timer with 30 yr experience. Have to say I don't understand anything here.

    • Thanatos
      Thanatos 28 days ago +4

      Make sure to check out the update video released today, he mentions a few mistakes made and clarifies further

  • EtherFi
    EtherFi Month ago +55

    I'd like to re-imagine this question a little. Let's not stop at a wire that's 1 lightsecond long. Let's make it 1 lightyear long. Now, let's turn the bulb on and off at one second intervals. According to this, the bulb turning on and off will still happen nearly instantaneously vs the switch. Now, tell me what happens when someone half a lightyear away cuts the wire....

    • Commenter Of Truth
      Commenter Of Truth 14 days ago

      ​@Andrew Seligman Id say the fields react immediately, as they arent some kind of choice making entities. but their produced fields arent running like they were a moment ago, so they 'begin' to shrink their field i.e. energy. so if the system is disrupted, it ends at the speed of light.

    • Visa Valpola
      Visa Valpola 23 days ago

      ​@Jenni Armstrong The formula veritasium used and the point of the video was that for some energy to get to the lamp it will not matter how long the cable is. For some energy to get through the only thing that matters is the distance between the switch and the lamp. So the 1/c s in the video should be 1m/c which is 1 m / (299 792 458 m / s) which is about 0.0000000033356 seconds. I said that a small amount of energy would get there almost instantly which was referencing this time. It is not however the full voltage and it does not travel along the wires and therefore the lenght of the wire does not matter for it. But as it is only a small part of the electricity I pointed out that for the full amount you would take a lot longer and that amount is not insignificant. The point of the video isn't that most of the energy doesn't travel in the magnetic fields very close to the surface of the wires (which is why we use them) but that many people don't understand that the energy is actually transmitted through fields and some of those fields can travel through air. He was not trying to deny that most of the energy follows the wire just saying that contrary to popular belief some doesn't.

    • Visa Valpola
      Visa Valpola 23 days ago

      @Jenni Armstrong I did catch the point of the video it's just that it's missing a part of the formula the correct formula is 1 ly/c for the full energy and 1 m/c for the partial energy. Veritasium missed the unit of distance in the formula and admitted to it in a later video. It's not a big problem to do that but apparently it has caused you to misunderstand the calculations.

    • Jenni Armstrong
      Jenni Armstrong 23 days ago

      @Visa Valpola you didn't catch the point of the video. The formula for a 1 light second cable is 1/c seconds for the lamp to light. Ergo, if the cable is a light year, it takes 1c years for the lamp to light.

    • Andrew Seligman
      Andrew Seligman 28 days ago

      @Visa Valpola Thanks Visa. That makes sense.

  • Bobby P
    Bobby P 6 days ago

    I love how in the beginning he states that he as a teacher propagated the myth that electrons carry the charge and then they all proceed to laugh at how dumb people are for believing it.

  • Joe Peng
    Joe Peng Day ago

    Would this still hold true for sending information, say, along network cable? What if the cable is not metal wire but optic fiber?

  • Coach
    Coach Month ago +470

    I could watch this 1000 more times and my brain would still believe electricity is either witch-craft or magic.

    • Coach
      Coach 11 days ago

      @IT Security Solutions, Inc. Ok

    • IT Security Solutions, Inc.
      IT Security Solutions, Inc. 14 days ago

      As an Electrical Engineer, most of technology which is not understood is said to resemble Magic. Electricity is not Magic, just energy which is everywhere. If you consider this Magic or Witch-craft, that may be your Paradigm.

    • Mike Steele
      Mike Steele 14 days ago +1

      @Herner Weisenberg he is not a lay person - he has at least a masters degree in physics and was a college physics professor. Also, the guy behind the channel itself has a PhD in physics education. They frequently educate other physics professors.

    • Limitlez
      Limitlez 15 days ago

      @InuranusBrokoff Thunderfoot is not a reliable source either. Maybe he's gotten better, but a couple years ago, he was realllly bad

  • Mareinna Shaw
    Mareinna Shaw 17 days ago

    So. What's your thoughts on the electric universe theory by thunderbolts project? I've been following them for years and it reframes so much of what we know... I feel like a lot of standard science these days is analogous to the issue that very few people know how electricity in a simple light bulb circuit works.

  • Keanu Miguel Ninobla
    Keanu Miguel Ninobla 29 days ago

    Hi Veritasium. Your fan from the Philippines. This video makes sense. It is easier to visualize our science teacher's teachings about electricity than this. That is why it is so hard to understand. Thank you for explaining it better and opened my mind.

  • Kenneth Shafer
    Kenneth Shafer Month ago +8

    So here's my question: What happens when you add another switch way out equidistant from the bulb and the battery? So that the information "the circuit is complete" has a necessary lightspeed delay?

    • J Modified
      J Modified Month ago

      The initial induced current at the bulb will be exactly identical whether the second switch is on or off, until distance_between_switches / c. That induced current does not require a complete circuit.

  • Jack Edward
    Jack Edward Month ago +1

    Every time I watch this channel I feel like I’m failing a science test :(

  • Geologian
    Geologian 6 months ago +180

    So, viewing the energy transfer as field and flux makes a lot of sense, but how does resistance actually draw power out of the field? Does putting an additional resistor in a circuit warp the field? What about resistance in the line? Really cool stuff, I think you're gunna need a follow up video that deals with the details and minutia.

    • 3dw3dw
      3dw3dw 6 months ago +1

      When we think in terms of dimensions specify the measurement of a height dimension from a width, or depth dimension. We can easily recognize that we have 3 spacial dimensions to work with. But what if we have more? What if electrons occupy or even comprise another spacial dimension. One that also contains the FIELD or magnetism. Suppose electrons are in a different spacial dimension than the nucleus of it's atom and there is a force that ties them together. We may even find that the spacial dimension itself is the electron, or more to the point the only electron. I know what I am saying is tough to agree with, especially we we've accepted that we know so much, but once upon a time we thought we knew the earth was flat and we were willing to burn people alive for suggesting otherwise. Please do consider the spacial dimension where the field resides as integral to the universe and yet independent of height width and length as they are independent of one another.

    • kashu
      kashu 6 months ago

      @FloPhysics the poynting vector will be pointing inwards; resistive wires draw in power to maintain the work being done on the charges to keep the same current while going through the resistive material

    • kashu
      kashu 6 months ago

      resistors draw power when current flows through them, this current is due to an electric field through the resistors and it produces a magnetic field around the resistor boundary. we thus have electric and magnetic fields just outside the resistor aligned such that the poynting vector points inwards and so there is an overall flux contributing to the work done on moving charges internally, generating heat!

    • Cheshire
      Cheshire 6 months ago

      The resistor slows electrons down (through impurities in the conductor material among other things). This is also a form of acceleration and thus creates an electromagnetic field. This field cancels out part the existing field around the wire and thus saps off some of the energy flow.

    • Robert
      Robert 6 months ago +1

      The electric and magnetic fields associated with the EM wave excited electrons that then lose that energy through collisions with atoms in the conductor. So the current saps energy away from the poynting vector. If you notice all the poynting vector lines converge at the light bulp, that is where the currents effective sap that energy away from the EM fields and transfer it to heat

  • Matthew Wilson
    Matthew Wilson Month ago

    Love this. Could you gain further proof through the thought exercise of a field around a wire traveling at a different rate (or the overall impedance of a wire being lower) if the wire was in the vacuum of space vs the wire being in Earth's atmosphere? I know you mentioned the Atlantic telegraph cable. I am surmising that the the traveling electromagnetic field must interact with any substance surrounding the wire (to a limited distance) in some way.

    • Matthew Wilson
      Matthew Wilson 28 days ago

      @J Modified Thanks very much. I'm a biologist trying to make materials for a welding class and want to make sure I am not just reinforcing the incomplete ideas I was taught.

    • J Modified
      J Modified Month ago

      Sure, this is a common experiment done by EE students in an EM fields lab course - verifying that signal speed depends on the medium surrounding the wire, such as insulation vs no insulation. I did it myself when I was an EE student 30 years ago.

  • Diário de um casal viking

    I like how Derek presents a scientific paper in form of a video.

  • Dale Simmons
    Dale Simmons 26 days ago

    Excellent video!! Your next video could explain how the impedance in the wire is related to the 'current' it can carry.

  • Antoni Strzałkowski
    Antoni Strzałkowski 4 days ago +1

    Does all of that mean that the circut didn't even need to be closed, as information couldn't travel to its edges before the light bulb turned on?

  • Dalnore
    Dalnore 6 months ago +312

    That's a great video about power transmission! I remember being surprised by that in the university.
    I really don't like the 1/c answer, though. While it's technically true that there will be some voltage on the lightbulb after 1/c simply because the electromagnetic fields generated around the wire will reach it, but it has nothing to do with them being connected by wires. In the same way, you can say that turning on this battery will "turn on" every single lightbulb on the planet. This is also technically true, because there will be some field generated by the battery in the entire space, and it will induce some voltage everywhere. Although its value will be negligibly small, as the magnitude of fields around the wire quickly drop with the distance from it. Only after 1 second, the proper connection through the electromagnetic mode of the wire will be established.
    If you replace the wire with an ideal coaxial cable (which doesn't let any EM fields outside the inner space between the two conductors), the answer will always be 1 second, as there's no leakage and thus no way for the lightbulb to receive the EM energy from outside the incoming cable.

    • Fourth Root
      Fourth Root Month ago +1

      @Antonio Monzon Derek didn't have meters in the numerator. 1/c is not the same as 1m/c.

    • Antonio Monzon
      Antonio Monzon Month ago

      @Fourth Root [m]/[(m/s)]=s
      No unit problem there.

    • Fourth Root
      Fourth Root 5 months ago

      @wbeaty "1/ c" is not a number.

    • Fourth Root
      Fourth Root 5 months ago

      @Dalnore 1 m / c would be correct. But that's not what he wrote or said. He said "1 / c seconds" which is completely different and totally wrong.

    • wbeaty
      wbeaty 5 months ago

      @Fourth Root Agreed! Dereck was using expert-speak here, perhaps appropriate for talking with physicists. But he's supposed to be informing beginners, not speaking jargon with fellow experts. It's only 3.3nS or "1/c" in seconds, because of the 1M gap, and this improper use of units keeps the fact hidden.

  • Daniel Zubovic
    Daniel Zubovic Month ago +3

    What's awesome about this explanation is the implications of wireless charging and power delivery. It's only a matter of time before we figure out how to have energy just flow through the air, without the need of all these wires everywhere. The future is wireless

    • LuckyDrD
      LuckyDrD 25 days ago

      Nikola Tesla was working on that.

    • Herner Weisenberg
      Herner Weisenberg Month ago +1

      The claims of this video are misleading. Ask yourself this: if the energy is not conducted in the wire but by the field, how comes your wires will melt if you bridge your breakers and draw too much power through them? ;D

    • Don McNevin
      Don McNevin Month ago +1

      If they can solve for telecommunications, navigation and radar maybe. But you also can't just create a huge voltage potential floating around for someone's kite to stumble upon. That's kind of mother nature's job.

  • patrick sohacki
    patrick sohacki Month ago +2

    I discovered this myself when I was playing with one of those lightning plasma balls and my Xbox 360 would turn off and on/ open its disc door depending on my finesse. no way I'm the only one

  • Nico Rösel
    Nico Rösel 4 days ago

    So moving the bulb and the battery to the outer sides of the cable (so that their distance would be 1 light second) would increase the reaction time of the bulb to 1 sec?

  • tom thibodeau
    tom thibodeau Month ago

    Great video, big fan. The central point of this video is well taken, and it provides an opportunity for us to think about what nature is actually doing in these situations, this a diamond in the rough as far as an EE topic Thanks... that said the answer is E not D. Because the loop area of this wire would introduce inductance. Quick search of online calculators puts this inductance at 0.636H, sounds low but that is good enough for this analysis, I propose the follow setup. Battery voltage =12V. Light source power 10W. this gives a steady state loop current of 0.83A. If we assume the light source needs to reach this 10W level to "turn ON", it will take 44.1mS for the light to turn ON...There is also a capacitive affect as well which would also increase the delay.Both of these are opposing fields.

  • Honor4OP
    Honor4OP 6 months ago +118

    If physically possible, I would like to see a video in which a disturbance in the field interrupts the light from switching on/off regardless of a wire moving electrons. I believe it can serve as an amazing example of how the energy is stopped or negated through the air rather than through the wire (:

    • Marc Fruchtman
      Marc Fruchtman 6 months ago

      @Leon Buijs Hmm, probably you were taught about it but didn't internalize... When they talk about electric charges that is the electric field. When they talk about the electromagnetic wave that is the moving part that gets induced by the moving charge.
      You can have an electric charge (battery or capacitor)... that is static (not moving). When it is static there is no EM field.
      When the charges move (whether positive or negative) then the EM field is created.

    • Leon Buijs
      Leon Buijs 6 months ago

      @Marc Fruchtman The EM field is one thing. The electric field is the most overlooked part. I never even heard of it in physics class, found out only recently.

    • Amy G
      Amy G 6 months ago

      YES this is exactly what I was thinking the whole video

    • Marc Fruchtman
      Marc Fruchtman 6 months ago +6

      @Phillip Otey How much insulation do you need to stop an electromagnetic wave that extends into infinity? It's not possible. Instead, think of it this way... the energy of the EM Wave in the air or free space is inversely proportionate to the square of the distance, so, very very little energy is reaching the bulb 1 meter away thru the air. It is NOT enough to light the bulb. Veritasium is making a mistake.

    • Phillip Otey
      Phillip Otey 6 months ago +3

      You could add insulation between the wires and the conductive sphere.

  • Briz KT
    Briz KT Month ago +3

    I'm a Master Electrician who has an EE degree. I very much understand the science, but there is a disconnect between the explained science in this video and practical application.
    The physical mass of the conductor has to play a part. If it were strictly true that current flows around the conductor rather than through it, why aren't conductors hollow? Imagine how much copper could be saved by running a 1/2 copper pipe instead of running 500 kcmil stranded wire. Some may say, "look! You said stranded wire," like the space between the strands makes a difference. Strands for this kind of wire is not for conductivity, but to be able to bend it. I think a simple experiment can at least shed more substantial light. The control is a standard 500 kcmil wire with 37 strands with a resistance of .021 Ohms per 1000 feet. Experiment conductor 1, is a 1/2 copper pipe. Experiment conductor 2, use 37 strands that are the same size of 500 kcmil wire, but loosely separated. My solid hypothesis is the standard 500 kcmil will conduct the best, which still begs the question of the validity of the claim that current flows "around" conductors" as opposed to through. I do not disagree that how we observe the flow of current through a conductor is detecting the magnetic field around the conductor. What I think is a more likely explaination is that the field emanates from each and every copper atom.
    Another experiment is taking a long conductor and test the shift of electrons with a strong enough voltage applied to one end. With a scale sensitive enough, I would like to see if the end with a strong positive voltage applied will weigh more than the side with the negative voltage. This would indicate a shift of electrons from one end of the mass to the other. Even if I'm wrong, such an experiment would still be fascinating.

    • Commenter Of Truth
      Commenter Of Truth 14 days ago

      I see it as fields existing where they will exist. and if theres a hollow wire, the entirety of the field will be effected in some way because the way it which it is flowing energy. it is producing exactly the same field if there is no physical altercation to its energy production. but since the field exists from a different environment, it will be different, some how some way. maybe not even percievable, unless the actual energy or other aspects are changed, but if its JUST made hollow, with no alterations to the energy its getting, I dont see it altering how fields are produced, atleast, the amount of energy or the size of the energy would be the same quantity.

    • J Modified
      J Modified Month ago +1

      "If it were strictly true that current flows around the conductor rather than through it, why aren't conductors hollow"
      Current flows through the conductor only. Energy flows around it and not in it, or at least that is a reasonable way of looking at it.

  • Cristian Jansenson
    Cristian Jansenson 6 days ago

    I am still missing something in this explanation: Where do the electrons that move inside of the conductor come from?

    • Jakub Znojemský
      Jakub Znojemský 6 days ago

      Well everything is made from protons and electrons and metals have electrons connected quite freely which makes them good conductors so you have some e- in by default
      and then if you use batery it has inside chemical reaction which produce excesive electrons on one pole and shortage of them on the other resulting in voltage and possibly direct current.
      Or you can have alternating current generator which is more tricky it transforms motion via electromagnetic induction into voltage. Not sure about this one but since all the phases (ACDC poles) of generator come from coils it just makes the same electrons run back and forth in loop through whole cirquit.

  • William Mitchell
    William Mitchell 4 days ago

    This video is more proof that we still don't know what electricity is and how it actually works. These "misconceptions" being taught in our education system are known to be false, yet are still being taught. This behavior is not limited to the subject of electricity. A major part of our education problem is that we are teaching things we know are not true and we are teaching things we cannot prove. Until we separate fact from fiction, the world's education systems will continue to suck and all scientific research will continue to suffer no matter how much money is thrown at it.

  • Rusty yB
    Rusty yB 14 days ago

    While an EM field exists around the wires, due to electron flow, the wires carry energy. Any inductor stores energy, but the electrons must keep flowing to support the EM field. Trying to cut off the electron flow will force the EM field to essentially expend itself in a traumatic way unless an outlet for the energy is provided.

  • lv8pv
    lv8pv 6 months ago +170

    My grandmother lived on a very remote and isolated island in Norway. When they first got electricity, they had one lightbulb connection hanging from the ceiling in the best living-room (it was only used when having fine visitors). The thing was that when the electrician first lay out the cables, they had no bulb to put in the socket. Also the electricity was not yet connected to the house but would be soon. So each night they put a bucket under the empty socket just in case the electricity would be connected while they was sleeping. Not to spill anything on the floor.

    • lv8pv
      lv8pv Month ago +1

      ​@michange3141592 hehe my mother saw a television the first time when her father brought here with him to visit someone in the city. After a good long while she ask her father why they had a small man inside a box

    • SkyLark
      SkyLark Month ago +1

      They applied themselves to understand it . They even respected it. Interesting

    • creative intentions
      creative intentions 6 months ago +3

      That's crazy. It's not water

    • Cmdr Sighman
      Cmdr Sighman 6 months ago +4

      I have a friend who turns off the switches on all his unused power points - not because of safety, even though that's sensible - but because he believes electricity pours out when there's nothing plugged in, wasting his money.

    • michange3141592
      michange3141592 6 months ago +8

      A colleague's grandparents, living on farm land in Belgium, would dress up on Sunday to watch television, thinking the presentator was actually talking to them and did see them.

  • Kyle Crawford
    Kyle Crawford 3 days ago

    So he never did directly say it, but was the actual energy field travelling straight from the battery to the nearby bulb, like outside the long circuit? That part wasn't clear since it contradicts the vector he describes. I swear this only made it more confusing.

  • dan428
    dan428 8 days ago

    I usually understand all these science videos pretty well but this one pretty much boggled my brain to a mush.

  • Xavier Cebeira
    Xavier Cebeira Month ago

    So I can understand why cables would be magnetically shielded to avoid interference, however would this not also drastically increase the impedance?

  • Casey Teate
    Casey Teate 3 days ago

    Didn’t Leedskalnin say this in some esoteric way a long time ago? I think it was something very close to this. He definitely said conventionally accepted knowledge on the matter was wrong.

  • Kamil Pekala
    Kamil Pekala 6 months ago +110

    Oh yes, please do an experiment in the Mojave desert! Also let's check a few more variations:
    1. arrange the circuit in a circle - that way the shortest path through space would be the diameter
    2. enclose stuff in a Faraday cage to block the fields from taking a shortcut and see if it lengthens the time to light up the bulb

    • MyNameIs
      MyNameIs 6 months ago

      WHAT IF the both wires go half the distance to the moon and back in the same direction ( not in the opposite directions as it is here)???

    • necron 1050
      necron 1050 6 months ago +2

      the faraday cage might not be possible it depends on the wave length of the EM weather it works or not. if it is possible it would be really interesting

  • Felipe E. Galindo
    Felipe E. Galindo 23 days ago

    I have watched this video 4 times. I understand the subject well now, yet I still enjoy watching it again every couple weeks

  • Chris Pergrossi-Contin

    This is well-made! Great job! However, the electric field DOES flow continuously between A and B, transmitting energy from the power station to your house. Electrons are formed in an positron field, which is easily resembled by an “electric” field. Anyway to test: an electric field always has exactly 1 ground, and a polar-high, so find ground from voltage!

  • Jay Bee
    Jay Bee 21 hour ago

    Intuitively my guess is E, electron movement should follow quantic law where time may not be relevant to allow for intrication.

  • Jarno Langenbach
    Jarno Langenbach Month ago +2

    I was once taught in school that there are always electrons in the entire wire, this way if one electron pushes on one side, another electron gets pushed out the other side. This way a light would turn on almost instantly (not instantly because it takes some time for the electrons to move). Would this explain the 1/c answer of the question if the light would turn on at any current?

    • Morbad th' Worst
      Morbad th' Worst Month ago +1

      @Box Fox That's a nonsensical question. You may as well be asking "what if a duck wasn't a duck"? The speed of light in a vacuum is a universal constant; it doesn't really have anything to do with light specifically...light itself often moves far slower than *c*. Anything faster than *c* would violate general relativity. So far, nothing has been observed to do this...our tests keep getting better and we keep demonstrating that the law holds. Nothing needs to move faster than *c* to explain any phenomena actually observed to exist.

    • Box Fox
      Box Fox Month ago +2

      Man doesn't know all forms of energy. Light may not be the fastest energy. Only the one man knows of.

    • Box Fox
      Box Fox Month ago +2

      @Morbad th' Worst what if light isn't the fastest form of energy?

    • Morbad th' Worst
      Morbad th' Worst Month ago +2

      No, because that would imply you were transmitting energy faster than the speed of light, which is impossible. Even if you had a completely inelastic/infinitely rigid rod that was one light-second long, it would still take one light second for the opposite end to start moving if you pushed the other end. Those electrons at the far end of the wire in this example are the same way; they take at least a second to start moving. The reason the example would work is that ones in and around the bulb are much closer.

  • Thomas Henderson
    Thomas Henderson 6 months ago +170

    The magnetic field is definitely there. Whenever I'm welding steel and the floor hasn't been swept in a while the steel filings align with my earth lead, which leaves some nice patterns!

    • Thomas Henderson
      Thomas Henderson 6 months ago +2

      @flawn And that's cool. 👍🏻

    • flawn
      flawn 6 months ago +3

      @Thomas Henderson everything cool, was just trying to uncover a possible misconception of yours 👍🏼

    • Thomas Henderson
      Thomas Henderson 6 months ago +8

      @Felix @flawn I'm neither debating or claiming anything ground breaking. It's just cool that it's a visible example of the phenomenon and I thought I'd mention it for those who may not typically come across it.

    • Felix
      Felix 6 months ago +6

      @flawn No one said it was.

    • flawn
      flawn 6 months ago +3

      That's not what's in debate. This is a given for a long time. It's the way the energy gets transmitted. Most think over electrons but we just have gotten it explained otherwise

  • swicked
    swicked 27 days ago +1

    Flowing electrons create a magnetic field around them and magnetic fields cause electrons to flow. It's like how mass can't exist without gravity and gravity can't exist without mass. What seems like two different things is one thing.
    Case in point(s): That's why electric induction motors, ones that take in flowing electrons to harness their magnetic fields to generate mechanical energy, are also electric generators, ones that can take in mechanical energy to harness magnetic fields to generate flowing electrons. You can have breaks in the wires between power plants and your home be bridged by inductors that allow the magnetic fields generated by one side to create flowing electrons in the other. The undersea cable's potential was getting drained due to the magnetic fields inducting flowing electrons in the conductive outer shell of the cable... electrons that would then be grounded out in the water. Electromagnetic Pulses are destructive to electronics because the high-powered magnetic field causes electrons to flow in anything conductive that the EMP interacts with. The EMP itself is created by a lot of electrons flowing at once.
    This aspect of electricity isn't that complicated, really. You just need to stop seeing flowing electrons and their magnetic fields as two different things.

  • Roi Baer
    Roi Baer 12 days ago

    Maxwell showed that the electric current is composed, in addition to the rate of particle flow, also to the rate of change of electric field (he called it the displacement current). You could discuss this. It's probably relevant...

  • Donnie Donnie
    Donnie Donnie 5 days ago

    If your explanation is true, you could cut the wire loop at the farthest point away from the bulb/battery and when the switch is on the bulb would turn on. By your example the field is there before it can complete the path, so cutting the loop shouldn't change the result.
    To me this is very similar to quantum entanglement (a connection that moves faster than light) if your experiment is accurate. My example above should prove this, if the bulb doesn't receive energy by breaking the loop at a vast distance away, somehow the energy backs up time (knows the path is complete) and is at the bulb faster than electrons are moving there. Spooky action at a distance? Maybe there is more to this than you first thought? Regardless, very interesting to think about.

  • tacoma rebuild
    tacoma rebuild 3 days ago

    haha, I love how the physicist laughs at how wrong we are understand electrons. well, there's science and academics for ya... if I had a dollar for everytime I was taught wrong by scientist. stop teaching us wrong in k-12 and college then.