The Big Misconception About Electricity

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.

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References:
A great video about the Poynting vector by the Science Asylum: thmy.info/dev/e5mpgauYlaWsp6E/w-d-xo.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

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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

ความคิดเห็น: 62 323

  • DeSinc
    DeSinc2 หลายเดือนก่อน

    but wait.. how can that be possible? what if someone cut the wire at the end and then at the same time you turn it on? does it still turn on instantly, but then "realises" 1 second later that the wire got cut and turns off again? I guess from your perspective, you would be turning it on first, and then from your frame of reference you would PERCEIVE the other person cutting the wire only 1 second later, despite them doing it a second earlier from their frame of reference.. edit: but what about signal reflections? what are they then? what the heck was I dealing with with ADSL ports having the signal reflected back to the first wall socket from the disconnected wire leading to the 2nd wall socket? and why do RAM traces on motherboards suffer from reflection?

  • Rien van der Voorden

    Rien van der Voorden

    หลายเดือนก่อน

    @Baconstrip so can we finally agree that things can happen at the same time? All this talk about relitivity just clouds the entire discussion. I mean, you seem a smart guy, im pretty sure you could have thought out the last example yourself. The second part of your answer again…not needed.

  • Kevin Barone

    Kevin Barone

    หลายเดือนก่อน

    What if the switch was at one of the ends of the infinitely long circuit? If the battery and light bulb are still 1 meter apart, yet im insanely far away from the light bulb, would i be able the throw the switch on and off and communicate information to the people standing around the light bulb instantaneously?

  • Baconstrip

    Baconstrip

    หลายเดือนก่อน

    @Johnathan Killebrew No, thought actually travels significantly slower than light

  • Baconstrip

    Baconstrip

    หลายเดือนก่อน

    @Rien van der Voorden Yes, they do, because they are in the same inertial reference frame. Regardless, the concept of relative simultaneity refers to two spatially-separated events occurring simultaneously in one reference frame and non-simultaneously in another, yet in your thought experiment I only see one event occurring (the snapping of the mechanic's fingers). Say the cut and the lightswitch happened at the same time in the mechanic's reference frame, though. If there were another mechanic, zooming by at a relativistic speed towards the cutter away from the lightswitch, from his reference frame the cut happened well before the switch was flipped - and relativity states this is equallly true.

  • Rien van der Voorden

    Rien van der Voorden

    หลายเดือนก่อน

    @Baconstrip ok. Imagine this. Lets take the example of OP. Cutter to the east. Lightswitch to the west. They are precisly 1 lightsecond apart. Now add in an extra mechanic precisly in the middle. So 0.5 second to both parties. Its a vacuum. The mechanic in the middle snaps his fingers. Both parties get to see the fingersnapping at the same time. Or dont they?

  • Blub Bubbel
    Blub Bubbel4 วันที่ผ่านมา

    This is very interesting. But i was wondering what exactly happens when there are two lightbulbs in a parallel connection or a series connection?

  • Strike

    Strike

    21 ชั่วโมงที่ผ่านมา

    in a series connection, the voltage (U) splits between two lightbulbs with the intensity of the current (I) staying the same. And in a parallel connection it’s the complete opposite

  • Marlon Ruiz
    Marlon Ruiz6 วันที่ผ่านมา

    Thanks for your explanation. In high school I remember touching on exactly what you’ve demonstrated. The teacher said, as best as my memory will do justice, “the electrons that were at the niagara power station on the day they closed the switch have never left. The energy however, has been delivered reliably ever since.” As a result, I’ve always referrenced “energizing” equipment, homes, etc. because the electricity on the wire is just trying to get back to the transformer on the pole. (Im not a scholar, so pardon my “basic-ality”. I agree it’s the distance from the source that determines the speed to illuminate your lamp. I’ve had the luxury to energize and witness your truthful assertion, where a lamp using twice the conductor length, but near the source, visually illuminate before a lamp that is physically further from the source; but electrically closer to the source because it’s utilizing 1/2 the conductor length. I wish I had viewed this video before conducting my experiment. You did a better job than my initial circa 1985 explanation. I also better understand that photo of Tesla sitting calmly in a room with electrical arcs swirling around him. End of my ramble. Cheers

  • Marlon Ruiz

    Marlon Ruiz

    วันที่ผ่านมา

    @humanyoda I didn’t make a video of the event. I only had my team there to help. I really only did the experiment because the memory from high school just happened to possess me and tried it out. I only have my word of honour as evidence.

  • humanyoda

    humanyoda

    วันที่ผ่านมา

    Wow! Please try to find that video. I find this hard to believe.

  • Dagobah 359
    Dagobah 35915 วันที่ผ่านมา

    Derek, I agree about the electromagnetic field carrying the energy, but where you go wrong is that the electromagnetic field is spread out along the entire length of the wires, meaning that most of the energy is going to travel far away from the battery before returning to the light. A very small amount of energy will reach the light in 1/c seconds, but you'll have to wait the full 1 second for most of the energy to get there.

  • Angels world reading

    Angels world reading

    10 ชั่วโมงที่ผ่านมา

    I agree, on a dc circuit With no resistance or interference and low voltages, The entire length of wire on the positive or negative side of the switch will have the same voltage potential as the battery terminals they are connected to but like a static charge it's not enough current charge to say the light is on until close to a second (excluding negligible change from impedance at 12 volts, 1 meter away.) High voltage AC is quite different, you don't even need wires or a switch 😋

  • Mark Meyers

    Mark Meyers

    12 ชั่วโมงที่ผ่านมา

    @Simon S. I agree. The MIT application juxtaposed with this shows them to be completely different.

  • Simon S.

    Simon S.

    12 ชั่วโมงที่ผ่านมา

    @Mark Meyers Hi, Mark. I just got a chance to look into two of your info sources, and would like to get back to you together here. If not mistaken, the former link, the video - nfSJ62mzKyY at Bozeman Science, basically talks about Ampere's Law applied to determining wire current induced magnetic field, the Right hand rule too. The latter one, the MIT's research, however, is somewhat new, as it developed a magnetic inductive *resonant* coupling scheme, similar to traditionally used in power transformers, to deliver "nonradiative energy" from the power source to a 60W lightbulb over two meters distance involving two coils. What's also particular is they used a power source that produces 10MHz magnetic field via the first coil over to the second coil resonating to the source frequency , but I am not clear by their saying "One is connected to a power source-effectively plugged into a wall" so it must be of some device that generates 10MHz current source or the like. As a matter of fact, I could fully understand MIT's experiment and the theory behind it. My background is E.E. with a Master's degree in Power Electronics, particularly Induction Heating in 1992, although I migrated to wireless instruments later on. My point is that MIT's experiment is so different from what's done over here by this guy, who tried very hard to make believe that magnetic energy could fly to the bulb over some distance of his setup, once the switch is on. In one sentence, he neither utilized a 10MHz power source (a DC power source instead which produces some short momentary transient process at most), nor did he used anything to accommodate such as "magnetic inductive *resonant* coupling". Therefore, nothing could really be borrowed from MIT to convince people that his mechanism is as comparable, or at least in parallel. The above are just my insights in the sense of electrical applications. I could be wrong in some way but my intention is not to argue about anything. Incidentally, again, to convince people here one needs to answer most good comments here before it's really accepted. That's probably the way it is today as people look at things from all angles we might not pay sufficient attention into. Thanks Mark for providing the useful info.

  • Nitrofan69

    Nitrofan69

    14 ชั่วโมงที่ผ่านมา

    That is what he said.

  • Kuppili Jayalata patro

    Kuppili Jayalata patro

    วันที่ผ่านมา

    I understand you

  • Nino Nieman
    Nino Nieman13 ชั่วโมงที่ผ่านมา

    This made me think about electricity in a whole new way! I'm still not convinced it's an accurate portrayal of what goes on, although I'm sorry you have to flog some joint's tech products at the start and end. People like you should be publicly funded, you do an enormous amount for education, and describe things so clearly - even if they require the basics of a high-school science background to understand, still, that's a large population even if the material is (understandably) beyond most people.

  • Haven DeZeeuw
    Haven DeZeeuwหลายเดือนก่อน

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

  • Mhurgle

    Mhurgle

    5 ชั่วโมงที่ผ่านมา

    Congratulations on the Advanced Non-Understanding.

  • Pallid Bust of Pallas

    Pallid Bust of Pallas

    2 วันที่ผ่านมา

    top comment

  • C- Hawkins

    C- Hawkins

    2 วันที่ผ่านมา

    I love you. I’m going to keep watching it and maybe one day it will connect and it will be a bing go moment and it will all become clear.

  • Anthony Payne

    Anthony Payne

    7 วันที่ผ่านมา

    At the 12:19 mark he says that the magnetic field propagate through space to light up the bulb. What in the actual F? By that conclusion, every bulb in the area would light up, I mean, unless the magnetic fields only propagate to those bulbs connected to the wires completing the circuit. And that would mean, it’s the flow of electrons in the wire, not the magnetic fields around it.

  • Periklis Spanos

    Periklis Spanos

    9 วันที่ผ่านมา

    Me too I feel I am stupet

  • Koen Raad
    Koen Raad14 วันที่ผ่านมา

    Consider a simple DC circuit with wires that have non-zero resistance: the wire surface charge density is slightly higher if close to the power source, and is slightly lower if close to the load. The gradient in surface charge in the direction of the wire length gives rise to an electric field inside the wire, and that is parallel to the wire. This electric field induces an electron drift current inside the wire almost simultaneously anywhere in the wire, such that the friction force in the wire is exactly equal (but opposite in direction) to the wire-parallel electric force. Again, the physics of excess surface charges on (semi)conductors, in particular its highly dynamic nature, is very important for understanding even the simplest electric circuit. Just like the energy flow Poynting vector in DC/AC circuits, the dynamic properties of excess surface charge are not treated in physics or EE education. If you are lucky you learn that drift current velocity is about 100 micro meter per second, but you will not learn that excess surface charge flows with almost the speed of light.

  • Angels world reading

    Angels world reading

    11 ชั่วโมงที่ผ่านมา

    @ian bardon if it stays on for a little while and then turns off or dims off than we're taking about the capacitor in the led driver dissipating its charge slowly. If your led never goes off all the way, use a volt meter to test voltage between neutral and ground (it should be close to 0). Led fixtures may illuminate when there is a difference of potential between circuit conductors and the fixture housing.

  • ian bardon

    ian bardon

    วันที่ผ่านมา

    Hi, you seem to the man who can answer my question, if I have a power cut everything goes of but not my LED wall light's, what going on ?

  • Honor Vids

    Honor Vids

    3 วันที่ผ่านมา

    hmm interesting

  • RequisitionCanada
    RequisitionCanadaวันที่ผ่านมา

    Excellent video, I love the energy and passion!! Most of the misunderstanding about electro-magnetism seems to be due to Gauss observing distinct electric and magnetic fields. Interestingly, without motion of an electron a magnetic field doesn't exist, but what about permanent magnets? Seems like there is a breakdown here. Since Gauss ultimately did not account for the critical existence of elemental monopoles, and Maxwell built from these incorrect assumptions, the Maxwell/Gauss equations overcomplicate a much more elegant answer.

  • Improv
    Improv5 วันที่ผ่านมา

    That was absolutely fascinating. Thank you for pointing this out. I had an inkling about this since I knew that it was possible to remote tap high tension power lines by introducing conductors under it. There's a really cool demo where you can stick fluorescent light bulbs in the ground under them and they light up from the magnetic field, and if they run directly over your house it's theoretically possible to put a copper coil in your attic to draw current off of it. However I hadn't really considered the implications of what that meant. Thank you for drilling down on this =)

  • Фадиме Бекмамбетова
    Фадиме Бекмамбетова7 วันที่ผ่านมา

    Thank you for the video! It's really interesting and I really didn't think of the 1/c answer at first! I saw some nice papers on different interpretations of energy flux density. I don't know if anybody mentioned those already, but here they are: H. E. Puthoff, “Electromagnetic potentials basis for energy density and power flux,” Eur. J. Phys., vol. 37, no. 5, p. 055203, 2016. U. Backhaus and K. Schafer, “On the uniqueness of the vector for energy flow density in electromagnetic fields,” American Journal of Physics, vol. 54, no. 3, pp. 279-280, 1986. In the paper by Puthoff, the proposed energy flux density involves (scalar electric potential) * (current density) + other terms that would vanish at DC. So it's not wrong to say that energy can be attributed to electrons in the wires, but, since we are not looking at DC, it won't be as simple as just potential energy * current density.

  • Dylan Dailey
    Dylan Dailey2 หลายเดือนก่อน

    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.

  • Физхимия микромира

    Физхимия микромира

    3 วันที่ผ่านมา

    @Veritasium It is a pity for the author of this video... He does not suspect that Maxwell made several unfortunate mistakes 149 years ago, which were discovered in January 2021 by a nuclear physicist from Moscow, Cherepanov Alexei Ivanovich. He published his research on the website - "Researchgate" - Another explanation to physicists of Maxwell's mistakes, 01/19/2021-11/01/2021 . Cherepanov's conclusion - there is no "electric field" in nature - Maxwell invented it, there are no "electric charges" in nature - Maxwell invented them, there are no "electric forces" in nature - Maxwell invented them. Think about it ... Read Maxwell's treatise "Electricity and Magnetism" - the chapter "Electrostatics", and make sure that Maxwell made a gross school mistake.

  • John Adams

    John Adams

    14 วันที่ผ่านมา

    @DieserOmega No ideal if your being dumb or asking for something different then you state. In practical applications of understanding EE you can consider the 'laymen's' theory true & correct and it makes no difference from how a light works to a computer using it (ie on or off - binary 0-1 for a PC). If your asking about why some items in a computer use different voltage (often 1,3,5v for internal MB signalling and up to 12,24v for power usage - note it is more complex then this) then this video nor your comment makes sense and you be better suited earning an EE+CS degree from your local college if you want a full understanding.

  • Cheryl CHO2

    Cheryl CHO2

    14 วันที่ผ่านมา

    @Max Tepermeister It might be done with a laser bounce from the moon through a satellite, and measuring how far apart the satellite's signal distortions occurred. the length of time the distortions existed may indicate field strength?

  • Cheryl CHO2

    Cheryl CHO2

    14 วันที่ผ่านมา

    @Jeremy Would that depend on how far apart- wide rather than long- the circuit is?

  • Zielu13

    Zielu13

    17 วันที่ผ่านมา

    @Veritasium Derek, congratulations finally just get cought by yourself by your tricky question 😄😄 😎 As science enthusiasts I like this discussion a lot. It is not to be ashamed if you get something wrong from time to time, as long as we can educate on this mistakes and lern sth new. You probably are still correctd 99% of time.

  • Peter Loef
    Peter Loef7 วันที่ผ่านมา

    wow! I wished my electronics teachers explained it this way 25 years ago. I'm still struggling to grasp the consequences of this. If the energy is transferred by the fields rather than the electrons, why do cables get hot when there's a significant load?

  • Sasquatch Guy

    Sasquatch Guy

    วันที่ผ่านมา

    There is an electron field around not only the wire but between the copper/iron/metal atoms themselves. The path of least resistance is in the metal, but pushing it harder and harder isn’t the problem, the overal amount (Amperage) is what causes the overall friction. You can have 1,000,000 volts at .01 amps and you get a very fast blurp. But 1 amp at 1,000,000 volts would get a blast/pop. Wires can only hold so much amperage before they melt, and the electron fields get pushed further and further to their limits before they start bleeding around the cable, and can easily push past insulators. Arc blow in welding is one example of this, so you wrap a ground to concentrate the arc and help control heat as electrons flow from wire to metal… Anyways im ranting sorry

  • Piotr Ang

    Piotr Ang

    2 วันที่ผ่านมา

    Well, every transceiver 1/4 lambda dipol radio antenna is the consequence of this reasoning. At that radio frequency counted in MHz or GHz it can be just cm or meters long, and can be fed ANY alternating current at that frequency, although at the end there's just the END, no wire back whatsoever.

  • Roy Engle

    Roy Engle

    5 วันที่ผ่านมา

    Heat is the resistance to the flow of energy. Grade school physics!!

  • torben schmidt

    torben schmidt

    5 วันที่ผ่านมา

    as he showed, the electrons rub against eachother inside the cable. that causes heat.

  • rblibit
    rblibit13 วันที่ผ่านมา

    GOOD VIDEO! You obviously have WAY TOO MUCH fun making your videos! It has always been the "induced field" that carries the true power of the circuit, and not those lazy little electrons that have been stealing the show all these years . Those wires could be cut on either end and the light would work just fine if the conductors were close enough to induce current flow. Electricity is a true enigma to the newbies.

  • Dave Allan
    Dave Allan12 วันที่ผ่านมา

    I'm absolutely loving this video and all the reply videos! This has sparked so much thought, discovery, experimentation and conversation! Great work! Probably not what you were expecting, but the best things in life generally aren't!

  • Andrew Van Day
    Andrew Van Day9 วันที่ผ่านมา

    No wonder his students like the explanation with the chain in the hose, that can be understood. The rest just fried my head! What would happen if you took a small battery & bulb circuit and completely covered the wires in those little powerful magnets that you can make sculptures with, would the bulb light up if the wires were prevented from having a magnetic field? And how do hundreds of separate electrical circuits exist side by side tightly packed into a computer say if they rely on magnetic fields that extend out such a distance?

  • Sam Beckett

    Sam Beckett

    19 ชั่วโมงที่ผ่านมา

    It might be all the crack you've smoked.

  • ian bardon

    ian bardon

    วันที่ผ่านมา

    @QueenMarifa I have had many shocks from static electricity when touching my care door, and most wrist watches will not work on me, interesting to here your theory. Cheers.

  • Carter Mc

    Carter Mc

    4 วันที่ผ่านมา

    @QueenMarifa Yes, from the aliens

  • QueenMarifa

    QueenMarifa

    5 วันที่ผ่านมา

    @marx I’ll find a link and we have had free energy since the 1800’s

  • marx

    marx

    5 วันที่ผ่านมา

    Wow. You checked it? Where are did you put bulb?

  • ElectroBOOM
    ElectroBOOMหลายเดือนก่อน

    Well well well, stepping into my territory, eh?! I shall make a video about this!!

  • wiz kha lilo

    wiz kha lilo

    16 วันที่ผ่านมา

    قولو اخطيك متريستي ههههه

  • jack elliot

    jack elliot

    17 วันที่ผ่านมา

    @TudbuT agreed but I also believe electrons have kenetic energy it is fundamentally a moving object and hence has kenetic energy

  • Beast Monster

    Beast Monster

    หลายเดือนก่อน

    Nice

  • Maya Atelier

    Maya Atelier

    หลายเดือนก่อน

    Don't forget Tesla and his idea to lighten up the whole plant for free.

  • Philemon Chiro

    Philemon Chiro

    หลายเดือนก่อน

    😀😀😀 can't wait

  • Daniel Elmaleh
    Daniel Elmaleh12 วันที่ผ่านมา

    There is problem with this view, which is at the beginning of the Battery part. It is said that the electric field propagates through the wire... but electric fields propagate from a charge and their intensity depends on the distance... while in this video the electric field magically stays inside the wire and constant. This gets Maxwell's equations wrong. What really happens (as far as I know ! ) is that the electric field going out of the battery immediately to the wire provokes a current which in turn provokes a local concentration of charge which in turn creates the electric field and so on, so that the electric field propagates in the wire... but it depends on the presence of the electrons and their movement to carry the information even though the don't drift as fast.

  • Daniel Chappuis
    Daniel Chappuis13 วันที่ผ่านมา

    I just wonder if it'd be possible to "see" this magnetic field if the circuit was somehow inside a ferofluid.

  • Joe Don

    Joe Don

    3 วันที่ผ่านมา

    A "Bluto" magnetic filing style game may work... :)

  • Charles Carlson
    Charles Carlson8 วันที่ผ่านมา

    Great video about something I’ve wondered about from a conversation with Frank Oppenheimer many years ago. He basically said the electrons don’t move at all, and I couldn’t understand why, and actually he didn’t give me a very useful explanation at the time. But it has always bugged me.

  • Stephen J
    Stephen J2 วันที่ผ่านมา

    Great video! It made me imagine leaving an old magnet out in the sunshine on a hot Australian summer day and seeing if I could generate electricity

  • Randall Parker
    Randall Parkerหลายเดือนก่อน

    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

  • Peter Lehman

    Peter Lehman

    20 ชั่วโมงที่ผ่านมา

    @A2Z Bicycle touring RULES! (And I had forgotten that I had considered stealth-camping on hydro-cuts!)

  • Peter Lehman

    Peter Lehman

    20 ชั่วโมงที่ผ่านมา

    @MarkoZBogdańca Electromagnetic?

  • Ray A James

    Ray A James

    9 วันที่ผ่านมา

    @MucaroBoricua I was taught organic chemistry in school. Nothing racist about that. I actually applied that to making pharmaceuticals that are used by many. I also was taught Maxwell's Equations and how to build circuits. My kids are learning these concepts today. Racism is taught in homes and acted our schools and other areas. One love

  • ToughAncientSpark

    ToughAncientSpark

    14 วันที่ผ่านมา

    When we were redoing the kitchen in our house, we had the kitchen light fixture hanging down until the work was done. One night I was passing by the light in the dark to get a drink of water. As I passed the light, I thought I saw a flash of light. At first I thought it was a passing car or my brain short circuiting. When I passed it again the light shined. I was perplexed until I held the light. I then realized that it was the static electricity in my fleece robe that caused the electrons in the light to get excited.

  • Ron Arnett

    Ron Arnett

    หลายเดือนก่อน

    @Ziad Khayat That is what schools say they do. They pay experts a lot of money to tell them how to it more effectively. (including paying Biden's son in law) That is the takeaway that the children are left with. But maybe you are right. Maybe after spending the money and time on how to apply the principles of critical race theory to the classroom, the schools don't do it.

  • Bill Bopp
    Bill Bopp23 ชั่วโมงที่ผ่านมา

    Unless I am mistaken, this can be explained in a simple manner. Instead of extending the wires 300,000 km, then back again, extend them to infinity. Or leave them at a finite length and cut them at their extent. Then you'll have parallel transmitting and receiving antennas, one meter apart. (Works fine for AC, but even if DC, you can consider the moment contact is made, which is a short time of current change.)

  • Paul Sullivan
    Paul Sullivan6 วันที่ผ่านมา

    I found this interesting although it does go against what I was always taught that electricity is electrons moving through conductors. If this is the case and instead of electrons we use footballs and fill a tube one light year long (or about 6 trillion miles), if we push an extra football in one end a ball will immediately fall out the other end. To do this the balls don't have to move faster than light, just the speed the extra ball was pushed in. We know that electrons actually move through wires from atom to atom very slowly so using the ball analogy, as soon as you threw the switch the light would come on. The only exception to this would be if some atoms in the conductor were able to assimilate extra electrons. We hear different views from different scientists but maybe they are putting too much thought into the process and according to Occam's Razor the simplest solution is often the correct one.

  • J Modified

    J Modified

    5 วันที่ผ่านมา

    "if we push an extra football in one end a ball will immediately fall out the other end" It takes time for the impulse to move through the footballs, or even a single football. If footballs were solid, the speed would be the speed of sound in rubber (far from light speed), but since they are air-filled they act as springs and it is slower.

  • Edward Linzer
    Edward Linzer14 วันที่ผ่านมา

    Does your experiment work, when the load is one light second away from the source? Or does the field need time to build in? Will the bulb be dim at first and then brighten after a second?

  • TRO
    TRO13 วันที่ผ่านมา

    Interesting. Kind of a flashback to college physics days. Reminds me of finals where all the students were trying to visualize the flow directions with their hands in the air. I may have to break out the old textbooks and review what I've obviously forgotten in the last 35 years.

  • r33mote

    r33mote

    10 วันที่ผ่านมา

    reviewing the basics is important every 5-10 years...

  • Devin Baillie
    Devin Baillie2 หลายเดือนก่อน

    A fraction of the energy passes through the fields directly between the source and load, and another (larger) fraction passes through the fields near the wire. So in the idealized case discussed in the video, a small amount of energy passes through the air, and that's enough to light the bulb. For most realistic circuits with relatively short and widely spaced conductors, the amount of energy passing through regions of space distant from the wire is pretty much negligible, particularly since most realistic systems have a minimum voltage/current at which they'll activate. The answer in the video is only correct under the assumption that ANY non-zero current is sufficient to light the bulb. If the bulb in the video required a minimum voltage across it that was some fraction of the battery voltage, then it wouldn't light until a sufficient fraction of the energy from the battery arrived at the bulb. Most of the energy travels very close to the wire, but there are also paths directly from battery to lightbulb, as well as paths that follow near the wire partway and come back near the returning wire. So the voltage seen by the bulb will gradually increase as energy along each of these paths reaches the bulb, with the full voltage only showing up when the fields travelling very near the surface of the wire arrive (~1 second in the setup in the video where the wires are one light-second long from source to bulb).

  • Dragos Dan Mihai

    Dragos Dan Mihai

    หลายเดือนก่อน

    After 5 other video explain why this works or not. I think I got it, also he says in the begining that the bulb will light immediately when current passes through it. Very good video!

  • drizzt

    drizzt

    หลายเดือนก่อน

    @ptitnhane lol, exactly.

  • Timmy Brolin

    Timmy Brolin

    2 หลายเดือนก่อน

    I did some back-of-envelope calculations. Assuming a 10W bulb and 12V battery, the bulb will only receive 0.00084% power at 1/c. It will turn on fully at 1s.

  • Dan

    Dan

    2 หลายเดือนก่อน

    @Devin Baillie Oh no I completely agree, which is the big problem here. He's just treating the light bulb like a receiving antenna, and I am not sure he realizes that that really isn't how a light bulb gets its power. Yeah, the inductive wire coupling and the bulb are both acting as near-field antennae in this scenario, and yet he elects to ignore the wire coupling but still depend on the bulb coupling for his explanation. Very strange that none of the "experts" caught onto that fact.

  • Minh Trinh

    Minh Trinh

    2 หลายเดือนก่อน

    This is correct. They also address this in the slides in the notes.

  • Michael W Clark
    Michael W Clark12 วันที่ผ่านมา

    I am sure I am out of my depth, but my lowbrow, knee-jerk, reaction to your explanation would be to ask what would happen if you had a way to perfectly contain those fields so they could not project outside the wire or conduit circuit? Say you could somehow prevent the fields from propagating outside of the wire or at least no more than a minute distance? Would the light not illuminate in any way? Certainly, there are technologies that allow us to constrict or block an electric and or magnetic field from forming/propagating, yes? Ultimately I wonder how you actually test and measure this theory? There is no physical way-- at this point, as far as I know-- to create the circuit you described. Is this true?

  • dpasek1
    dpasek1วันที่ผ่านมา

    The magnetic field around a conductor is created as a result of moving charge carriers, in this case, electrons. Without moving electrons in a conductor, there is no magnetic field, and there can be no energy transfer. The point of there being transformers between generators and loads is irrelevant. A transformer is an application of the law of induction. It is just a convenient method of changing voltage according to the turns ratio: changing electric current induces a changing magnetic field which in turn induces a changing electric current in another isolated conductor. Static magnetic fields are the result of a constant movement of charge carriers. This is true even in a permanent magnet where the moving charge carriers are aligned atomic electronic orbitals. When you have a moving charge carrier, you also have an associated magnetic field. They are inseparable. You fail to explicitly mention this last point in your video, although you loosely imply the connection.

  • Randy M. Hernandez
    Randy M. Hernandez14 วันที่ผ่านมา

    Have you ever seen the wireless transmission of electricity? I have. Its amazing.

  • David Reidenberg
    David Reidenberg4 วันที่ผ่านมา

    Interesting, I seem to recall from college physics that the electrons flow at the outside of the conductor because they are trying to maximize their distance from each other because they are all like charges. Is that correct?

  • Eric L Michelsen
    Eric L Michelsenหลายเดือนก่อน

    I teach physics at the University of California, San Diego, including this very topic. Within an hour of watching this, I set up the experiment, and got the result. I have photographs of the experimental setup, and of the oscilloscope traces. I discussed the results at length with a physics professor friend, and we agree on the explanation. In fact, the load gets (nearly) the full voltage (almost) immediately; there is no (visible) ramp-up time, nor delay through the long wires (delay Update: I love the Veritasium series, and I have learned a lot from it. To respond to some replies: I chose the simplest case, which I think illustrates the point that power can reach the load without going the whole length of the "wings." The analysis link below the video covers the more-complicated case. My "wings" are 50' hardware store extension cords. My propagation test confirms that coiling them doesn't matter, as expected. My analysis is fully transient, and the circuit transits to steady-state DC over time. Resistance can safely be approximated as zero, but inductance and capacitance cannot, as expected by theory. My load is 270 ohm, roughly the on-resistance of a 50 W incandescent bulb. The characteristic impedance Z ~53 ohm, which is substantially less than the load; that's what's needed for the simple case of near full response nearly immediately (the load is _not_ matched to Z). In this case, the wing capacitance dominates the behavior. Consolidating my previous reply: Examples of subtleties: Do two electrons repel each other? (a) Most people would say yes, and I agree. But one could argue (b) No, one electron creates an electric field, and that field pushes on the other electron. This is also correct; it's slightly more detailed, and from a somewhat different viewpoint, but (a) is still correct, as well. But (c) In calculating the force of (b), we use only the E-field from one electron, even though we know both produce E-fields. To use the full E-field, we have to compute force with the Maxwell stress tensor; this is also correct. There are multiple correct views one can take. The video's chain analogy is very good, and correct. Separately, a few replies have hit on the most-direct (IMO) explanation: the capacitance in the wires provides an immediate, physically short path for the electricity to reach the load. The path of current changes over time. Your gut might tell you that the capacitance is too small, but a quantitative transient analysis using standard circuit theory matches the experiment. Special Relativity still stands. More subtleties: characteristic impedance, etc. I do similar demonstrations in class, so I happen to have all the equipment and experience ready to go.

  • Reese

    Reese

    9 วันที่ผ่านมา

    2022 is your year, 📣 _"Make sure the money works for you,"_ *🔍 BLACKPINK Lisa - MONEY* 🎵 : Hip-Hop 🎵to get energy

  • sparkzebra

    sparkzebra

    27 วันที่ผ่านมา

    @zafurchio Just think of its as cutting a path with a machete-the conductor provides a low resisitance or highly conductive connection.. and Tesla proved over a century ago wires are not absolutey required to transmit electricty between two points

  • Kris Krissison

    Kris Krissison

    หลายเดือนก่อน

    boss tier comment

  • jonathan horvat

    jonathan horvat

    หลายเดือนก่อน

    @Alejandro Lugo communication cannot

  • jonathan horvat

    jonathan horvat

    หลายเดือนก่อน

    @Larry Hecht radio shack

  • Iestyn Jones
    Iestyn Jones7 ชั่วโมงที่ผ่านมา

    Great video but I have a question. If you placed a second isolated loop of wire, having a bulb but no battery of it's own, within the primary loop the bulb in this second circuit would not light even though it experiences the electromagnetic field produced by the battery in the primary loop. I have questions as to why the energy is so efficiently focused on the bulbs within the primary circuit and the field doesn't seem to affect nearby circuits very much. From your explanation I would expect the induction effect on nearby circuits to be far stronger than it is.

  • Gagandeep Singh
    Gagandeep Singh13 วันที่ผ่านมา

    I learnt about drift velocity in my 10th class (a couple of years before University in India). In the book they said drift velocity is extremely slow then how the light bulbs turn on instantaneously, well now I know why. A question answered 7 years later. Thanks Veritasium.

  • King Kong

    King Kong

    12 วันที่ผ่านมา

    @Gagandeep Singh by the way your girl deserves more knowledgeable guy like me than you.. Bad luck for her..

  • King Kong

    King Kong

    12 วันที่ผ่านมา

    @Gagandeep Singh there tons of videos are made with a vast explanation against this bs. Mehdi, EE vlog and many others already uploaded those..

  • Gagandeep Singh

    Gagandeep Singh

    12 วันที่ผ่านมา

    @King Kong Well, then care to provide the correct explanation. Anyways, your comment reflects a lot about you than me. :-)

  • King Kong

    King Kong

    12 วันที่ผ่านมา

    Proven that you're an Indian lol. This video is full of errors.. Learn tye basic at first

  • IHT sarl
    IHT sarl7 วันที่ผ่านมา

    Thanks for posting. You touched on a very important concept that as an Electrical Engineer (M.Sc.) I always wondered.

  • izzideadyet
    izzideadyet14 วันที่ผ่านมา

    It's actually a lot more complicated than this when you get into quantum physics.

  • Ferarn McÆternitum
    Ferarn McÆternitum2 หลายเดือนก่อน

    Honestly, the analysis from the professors made a lot more sense to me than the video just from a small clarification that I didn't catch from this with one watch, and had left me very confused. The energy most are generally used to seeing from a long, wired connection is from the "transmission line" current, but the energy being talked about here is from "antenna current," and the two modes of transfer, along with major differences in voltage that actually reaches the bulb by either type, felt like important info to leave out. The implication I got from the original video was that the length of the conductor did not matter at all for this model, but the reality was just that the 1m distance in the math, and specification of "any" current, hid the conflicting nature of two modes. So, from my corrected understanding: The "transmission line" current *would* take one second to reach the bulb, through electron to electron EM field interactions in the wire, it's just that the "antenna" current can travel there first, because of a lack of shielding, and the misconception/lie here isn't so much a misconception/lie, but a lack of information on additional modes of energy transfer. It felt like this video was more focused on becoming a popular, trick question via omitting information, rather than informing people on new or misleading information, which is not something I would/could say about any other Veritasium videos I can recall, and I do not like to say.

  • Kit Kat

    Kit Kat

    22 วันที่ผ่านมา

    @CoolerSloth 5822 Which isn't relevant at all when talking about how electric energy is transferred from a power plant to your house, like Veritasium claims.

  • Matt Murphy

    Matt Murphy

    22 วันที่ผ่านมา

    @CoolerSloth 5822 the wire is the antenna

  • CoolerSloth 5822

    CoolerSloth 5822

    22 วันที่ผ่านมา

    in simple terms the current causes the battery to act like a antenna

  • Kit Kat

    Kit Kat

    หลายเดือนก่อน

    @Matt Murphy I was talking about Veritasium's explanation. Hence the "seems like". I was not attacking the physics you overconfident mango.

  • Jeffrey Hollocher

    Jeffrey Hollocher

    หลายเดือนก่อน

    I agree completely.

  • AmericanTrekker
    AmericanTrekker9 วันที่ผ่านมา

    This concept of energy propagation through force fields of electricity and magnetism is a powerful one! Unsaid in this video but highly relevant is that all the force interactions between light and other light and with matter are mediated by the exchange of virtual photons in the Zero Point Energy, as described by the physical science of Quantum Electro Dynamics, QED for short. It's not magic like it looks (!), it's physics. And awesome physics, holding the forces and coding for the physical manifestation of our entire universe, including ourselves in it. The ZPE is the Source of everything.

  • CarlosGunX

    CarlosGunX

    4 วันที่ผ่านมา

    Zero Point Energy field-: "The Mind of GOD".

  • Dietmar Steinhaus
    Dietmar Steinhaus3 วันที่ผ่านมา

    Okay, although I'm deeply interested in science my whole life I suck at physics and mathematics when comes to analize or predict outcomes. I can evaluate different answers when the reasons for them given. But, anyways, here's my try: I see the current as a chain reaction through the wire. So it could not be any faster than light. I feel encouraged by the fact that the gravitational waves also travel at light speed. And now knock me down with the real answer. EDIT: Wow! That answer enlightened me! (Great pun, y'all!)

  • Dietmar Steinhaus

    Dietmar Steinhaus

    2 วันที่ผ่านมา

    @Sociedad del Bienestar Mutuo, SBM UFOs. Yeah, sure...

  • Sociedad del Bienestar Mutuo, SBM

    Sociedad del Bienestar Mutuo, SBM

    2 วันที่ผ่านมา

    Think this, gravitational waves travel at light speed, electromagnetic waves travel at light speed. Gravity is just a electromagnetic effect? How UFO flight?

  • terry button
    terry button19 ชั่วโมงที่ผ่านมา

    In a dc circuit the electrons do indeed flow along the wire i.e. from one terminal to the other terminal - but with ac the current does alternate as you said (it does not move along the wire as with dc), but the amperage is the AMOUNT (or magnitude) of electrons alerrnating during each cycle

  • Dina-Anukampana Das
    Dina-Anukampana Das8 วันที่ผ่านมา

    Absolutely brilliant! You explain everything so well, and your graphic animations are fabulous! Thanks for making science so interesting and accessible! Genius!!

  • marcel zuziak

    marcel zuziak

    5 วันที่ผ่านมา

    @Dina-Anukampana Das How come, really?

  • Dina-Anukampana Das

    Dina-Anukampana Das

    5 วันที่ผ่านมา

    @marcel zuziak That was my sincere comment.

  • marcel zuziak

    marcel zuziak

    6 วันที่ผ่านมา

    Absolutely brilliant sarcasm 👍

  • Lone Kanne-Hansen
    Lone Kanne-Hansenหลายเดือนก่อน

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

  • Michael H

    Michael H

    25 วันที่ผ่านมา

    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

    หลายเดือนก่อน

    @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.

  • Jule Rulez

    Jule Rulez

    หลายเดือนก่อน

    Don't get carried away . His 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 !

  • henk

    henk

    หลายเดือนก่อน

    @Neo the Riot the fields are not going from the powerplant directly to your house. There are intermediary steps like things called transformers. Moving electrons create fields and fields can excite electrons.

  • Cad'ika Orade

    Cad'ika Orade

    หลายเดือนก่อน

    Considering this video is completely wrong, don't worry about it. This guy just "disproved" integrated circuits, like the kind you watched the video on. He's about as legitimate as the Flat Earth Society.

  • Rusty Highlander
    Rusty Highlander15 วันที่ผ่านมา

    If electrons don't flow in a circuit, explain the function of the cathode and anode in a vacuum tube. I can promise you that if you grab the B+ 500 VDC connection on a tube amplifier plate while holding the chassis with your other hand with the power on, 500 VDC will go across your heart and you'll never forget it if you survive.

  • Rusty Highlander

    Rusty Highlander

    4 วันที่ผ่านมา

    @Raptor Jesus Cathode ray experiments have verified the flow of electrons for a very long time. You should review J.J. Thomson and his discovery of the electron and the cathode ray experiment.

  • J. S

    J. S

    5 วันที่ผ่านมา

    @Raptor Jesus infact it is the flow of electrons . The emf voltage is to low to bridge the gap . You can measure the emf around the wire about 0.001 percent of the voltage in the line . The emf dissipates with distance .

  • Raptor Jesus

    Raptor Jesus

    8 วันที่ผ่านมา

    Your example does not provide a counter-point as the effect you describe could be caused by either the flow of particles or electromagnetic current.

  • Christian Lewis
    Christian Lewis8 วันที่ผ่านมา

    I’m so confused. How does the Poynting vector result in flowing in all local areas of space, eventually curving to the light bulb as if it know the light bulb is the ‘feature’ of the circuit? Electricity doesn’t know that the bulb is the item we’re targeting, the light bulb is just a different set of materials in the circuit that is allowing current flow. Most of the circuit is copper, then it flows through some tungsten, then back to copper and to the battery. What makes the bulb so special that the pointing vector goes straight for the battery and not other bits of the wire? Is is the very fact that the bulb is the most resistive section of material in the circuit that energy flows there? What if you take the bulb out of the circuit and just short the circuit straight to the battery? Where does the Poynting vector go then?

  • Roy Engle

    Roy Engle

    5 วันที่ผ่านมา

    The electron flow (energy) is AROUND THE OUTSIDE OF COPPER WIRE, not thru it!!!

  • Peter Valentine
    Peter Valentine15 ชั่วโมงที่ผ่านมา

    I read that the implosion fission bomb uses explosive charges in a spherical array, and that they must be electrically detonated as precisely as possible at the same time so that there will be spherical compression moving inward. For this reason, it was said, the wires connecting the power supply to the detonators had to be the same length. Were they wrong?

  • Marko Van Dango
    Marko Van Dango9 วันที่ผ่านมา

    I've never understood electricity, but I would like to, your video makes perfect sense, although from the minimal amount I 'know' or think I know, you have emf that supposedly provides the force to 'push' the electrons around the circuit, but in this instance completing the circuit provides the electromagnetic force (am I right)). Must admit, yours makes a lot of sense, very interesting, thank you.

  • Jonathan T
    Jonathan T2 หลายเดือนก่อน

    I have a question: Let's say the far end of that 300,000km wire was cut, then the light bulb wouldn't turn on, so in 1/c seconds I would learn that a cable that is half a light second away from me is cut. Doesn't this violate the idea that information can only travel at the speed of light?

  • Glenn Rogers

    Glenn Rogers

    23 วันที่ผ่านมา

    As a non-physicist I have this exact same question and am surprised that many repliers with apparent expertise in this area failed to mention this flaw which I believe is fatal to the presentation. Derek needs to comment on this or for me at least he will have lost all credibility.

  • I hate just some guy without a mustache

    I hate just some guy without a mustache

    29 วันที่ผ่านมา

    It would depend upon the reference

  • Epic Math Time

    Epic Math Time

    หลายเดือนก่อน

    @Leo Qvarnström Completely irrelevant. It doesn't matter what the human observer can "know" from the event. The point is that _causality itself_ is limited to the speed of light. An event cannot _cause_ another event to occur 1 light second away in less than one second. It is the speed of causality itself.

  • Joe Dziewa

    Joe Dziewa

    หลายเดือนก่อน

    @Grahamaan27 His algebra is certainly wrong, he apparently forgot to move the units along with the values in going from c to 1/c and that ABC are in seconds and D is in square seconds.

  • Olav Gausaker

    Olav Gausaker

    หลายเดือนก่อน

    @Weston Zavadil I disagree. If the circuit is open the electrons won't go anywhere. You just have some "pressure" (voltage) applied, specially considering the ideal situation Derek is describing with no resistance or capacitance. If that were true this would also work with a 1 meter long cable on the battery and on the lightbulb (disconnected from each other) placed as two parallel lines.

  • Dan Chadwick
    Dan Chadwick13 วันที่ผ่านมา

    This process can be demonstrated with charged ping pong balls, between charged rails with the same charge. With the charge pushing the ping pong balls centered between the rails, push with a nonconducting rod, one of the balls and they all will move. All of the ping pong balls will also be separated from each other by the charge on each of the balls. Watch what happens when you place a magnet near the path of the balls.

  • Scott Mckenna
    Scott Mckenna10 วันที่ผ่านมา

    I, for one took notes! Great stuff my man! Shocking information! (Pun intended) go and celebrate! You are helping open minded people understand the invisible world.

  • Piotr Ang
    Piotr Ang2 วันที่ผ่านมา

    2:34 that "plus" part is actually easy to explain: if you push your car in one direction, and stop, and then push it in the opposite direction - well, you don't wonder that the car is pulling you, it's STILL you pushing the car, just in the opposite direction, so the energy folow is obviously still from you to the car, regardless of the direction. Likewise, you DON'T really expect the light bulb to charge your battery if you change + and - (though the electrons obviously travel in the opposite direction).

  • shiladitya haldar
    shiladitya haldar3 วันที่ผ่านมา

    Some more understanding about the electric field and current flow in this video would have been appreciated for layman like us, however its a very interesting video about current propagation.

  • Zitao Qiu
    Zitao Qiu2 หลายเดือนก่อน

    Still having one doubt: I understand that energy doesn't need to travel through the whole circuit, but how does the light bulb know it's a closed circuit when you flip the switch? Let's say the wire is cut off somewhere very far away from the switch and the light bulb, information should still take time to travel instead of instantaneous. Unless it will work even if it's not a closed circuit, but this doesn't make sense either. It's like I can just flip a switch near a light bulb and it will magically work without a closed circuit. I know it may work without a closed circuit like a transformer, but this setup is not like that at all. Also, mentioned by Rick K in the comments: If this is true, then why don't we use that effect for "faster than light" data transfer? If the light bulb "reacts" to the switch almost instantly, that would mean that the "information" transferred with the flip of the switch is also transmitted instantly.

  • Mordea

    Mordea

    26 วันที่ผ่านมา

    Infromation along a cable to the other side of the earth does not move through the cable with speed around the earth but through the middle of the earth, namely along the shortest path through space-time with c.

  • Benjamín Calderón

    Benjamín Calderón

    29 วันที่ผ่านมา

    :0

  • Denes Kellner

    Denes Kellner

    หลายเดือนก่อน

    My thoughts exactly, I should have looked around before I post the same.

  • Blue Wings

    Blue Wings

    หลายเดือนก่อน

    The light bulb doesn't need to know anything. Incomplete circuit = stationary electrons in battery and wire (just simplification, they aren't actually stationary completely). Complete circuit = locally oscillating electrons in wire which generates the oscillating electric and magnetic field, and therefore the energy flux field that is also in the same direction towards the light bulb. The speed limit is limited by the speed of light.

  • Kevin VE7KWP

    Kevin VE7KWP

    หลายเดือนก่อน

    @Michael Geiss Hmm you have me doubting myself now.. let me think about it.

  • Drusilla Winters
    Drusilla Winters3 วันที่ผ่านมา

    Although this video and the others that I watched about it increased my understanding, I think it was a bad idea because I think it made the understanding of those who watched it and did not investigate further worse. Some just didn't believe what you said and some took away a misconception about electricity. This is too complex a topic to deal with in this way.

  • C- Hawkins

    C- Hawkins

    2 วันที่ผ่านมา

    So are you saying it’s better that people don’t understand electricity? I also thought electricity was “magic” and after watching this I understand enough to want to learn more. It’s fascinating and I love this world more everyday. The internet has changed my life.

  • John Bowman
    John Bowman3 วันที่ผ่านมา

    I had no clue...my dad knew this and could run a light off our barbed wire fence underneath high tension power lines.

  • Sara Timms
    Sara Timmsวันที่ผ่านมา

    The answer to the question is either C or D. The light bulb will come on instantaneous. C could be right. The problem is the value of C is not given but assuming it is used to represent the number of electrons, one over a very large number will be very close to instantaneous. Why will the light bulb come on instantaneously; because the wire is connected to a power source and the potential to do work is present in the circuit. Going back to the basics, you need three thing for a circuit to function, a load in this case a light bulb to draw current, a power source to provide energy and a completed closed circuit. When the switch is in its on position the circuit becomes close and the energy potential in the circuit will instantaneous light the bulb.

  • Peter Smith
    Peter Smith14 วันที่ผ่านมา

    Great video! It is always interesting when I learn that my comprehension of a subject is far below what I believed it to be. Learning is fun, and sometimes painful.

  • warrenvwilson
    warrenvwilsonหลายเดือนก่อน

    I know you predicted pushback, and with good reason, so here it is. I’m not saying this video is wrong, but at best, it’s incomplete. First off, the fields can’t intrinsically be separated from the flow of charges as if the electron drift isn’t significant. For the magnetic fields to permeate free space in the first place, the charges must undergo acceleration to create them, and if you cut off the switch, the fields would collapse without the current. If I turned on a fan next to a piece of paper and the paper flew away, would it be accurate to say that the air alone did the deed? Sure, the energy that moved the paper was transferred to it by the air, but neglecting that the fan moved the air in the first place would be a glaring omission. It’s also essential to remember that the Poynting vector itself is DERIVED from the continuity equation (local conservation of charge), and what it represents is the interplay between the energy transfer among the fields and the movement of the charges that generate them. In other words, fields don’t carry energy on their own without the movement of charge. Also, the vast majority of energy transfer in the fields happens extremely close to the wires, and the graphic that you’ve given of these fields taking such wild departures away from the circuit ignores the infinitesimal magnitude by which this happens. With regards to your experiment, the following should be noted. Yes, there would be some current flow instantly with the closing of the switch, but only because the electric field in the conducting wire has had time to reach equilibrium along its length. If instead of a switch, you connected the wires to the leads of the battery directly, the propagation of the electric field along the circuit would occur at a speed less than that of light in free space. Lastly, I challenge you to explain the energy release from the actual light bulb that doesn’t involve electrons flowing through the filament. Also, I posted the following as a reply further on in this thread, but I'm putting it here because it's important. The power (energy per time) that a circuit puts out is always IV (current times voltage). This relation makes no reference to fields of any sort. Now, it is absolutely true that the electric and magnetic fields carry the energy - the current does not - but when one takes the spatial integration over the Poynting vector, it always reproduces the power law P=IV. The fields carry the energy, but the current generates it. You can change those fields in a million different ways and the circuit will behave the same. For example, wrapping the wires in a grounded sheet of aluminum foil creates shielding, which is how high transmission data cables such as CAT6 or COAX reduce noise and capacitance between wires. You could say that they contain the electric fields within the space of the insulation. You could also coil the wires into an electromagnet. However you reconfigure the fields themselves, the fact is that the overall power dissipation of a circuit depends on the current, not on the field strength, and to trivialize this fact by focusing on how the energy is carried is confusing and misleading. As with my earlier analogy to a fan blowing air, the energy may be carried away by the air, but the amount of that energy depends solely on the power output of the fan. Ultimately this video has some good information, but it is also extremely misleading, and I caution people to take any claims that “they way you understand things is false” with a grain of salt. Usually, there’s more nuance than that, and as something of a cynic myself, I think it’s often a form of clickbait. I encourage interested viewers to look elsewhere for the full picture of electrodynamics in all its beauty.

  • mike K

    mike K

    14 ชั่วโมงที่ผ่านมา

    @Manuela N.S You have to read God's mind to understand it :)

  • Science Revolution

    Science Revolution

    หลายเดือนก่อน

    More BS. What is energy? What is energy fluxes? What is electric field? What is magnetic field? What is the carrier of the field? Where is the field? What is the content of the field? How field oscillates? Why electron does not accelerating to positively charged protons? What force or mechanism to make electron stay away from the nuclear? What carries electric field and magnetic field in empty space? If photons move at light speed from the sun hitting earth is fact, what speed and direction the solar system moves? Is there any drags from sea of photons in the space?

  • NautyEskimo

    NautyEskimo

    หลายเดือนก่อน

    @Commander ZiN Poyntings theorem is great when you need to talk about EM radiation, but yea for most electrical applications, electrons are perfect to explain things. Also energy is weird concept in physics in general as its not so much a physical thing that moves but a number to account for and quantify physical phenomena.

  • Commander ZiN

    Commander ZiN

    หลายเดือนก่อน

    @Foodie Girl aka Skater Girl there's value in the discussion if you tell it in a genuine fashion, without intentionally leaving bits out to create click bait and viral videos.

  • Foodie Girl aka Skater Girl

    Foodie Girl aka Skater Girl

    หลายเดือนก่อน

    @Commander ZiN But there is some value to the whole discussion- no?

  • Crumpred
    Crumpred3 วันที่ผ่านมา

    [To the DeSinc question] My guess is that the cut acts like a switch and the magnetic field does not react to non ferris metals, but to the electrons carried by them. How long does the bulb remain on once a switch is thrown?

  • Xero
    Xero10 วันที่ผ่านมา

    As an Electrical Engineer who has studied transmission lines, I am triggered, and I bet I'm not the only one. I highly recommend ElectroBOOM and AlphaPhoenix's response videos.

  • Sam Beckett

    Sam Beckett

    17 ชั่วโมงที่ผ่านมา

    @Xero Why are you celebrating?

  • Xero

    Xero

    18 ชั่วโมงที่ผ่านมา

    @Sam Beckett yay for you.

  • Sam Beckett

    Sam Beckett

    18 ชั่วโมงที่ผ่านมา

    @Xero Believe? I don't believe you

  • Xero

    Xero

    18 ชั่วโมงที่ผ่านมา

    @Sam Beckett you are welcome to believe whatever makes you feel good about yourself. 🤷🏻‍♂️

  • Sam Beckett

    Sam Beckett

    19 ชั่วโมงที่ผ่านมา

    you're not an electrical engineer.

  • EtherealToxin
    EtherealToxinวันที่ผ่านมา

    This would then imply that a Pure-Energy, Pre-Electrons, System, that can manipulate Electric-Field without Electrons & Magnetic-Field without Magnets, as in a non-matter system, could operate as if an Electric-Circuit. Assuming an Electric-Field is technically not exclusive to Electrons, on a pre-matter context, and Magnetic-Field is achievable without Matter, that is. From a (Pre-/Sub-)Quantum Energy Capacity. Force-Lightning in a Vacuum could then work, if they were separate and they could be engaged in from Spirit, from below. But the Arc-Effect of Lightning would not apply without Electrons in that scenario(, right?)

  • Xavier Maximin
    Xavier Maximin3 วันที่ผ่านมา

    Could cool to do an experiment where you can hide the fields with a insolator between the batterie and the Lamp to double check

  • John Chessant
    John Chessant2 หลายเดือนก่อน

    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

    2 หลายเดือนก่อน

    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

    2 หลายเดือนก่อน

    @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

    2 หลายเดือนก่อน

    @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.

  • UK man loves goddesses

    UK man loves goddesses

    2 หลายเดือนก่อน

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

  • sumilidero

    sumilidero

    2 หลายเดือนก่อน

    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'

  • Vancouverman
    Vancouverman11 วันที่ผ่านมา

    No lies were intended by instructors when they told their students about the "flow" of electricity, they are just using word pictures and mechanical models to explain an extremely abstract theory. We can't see electricity, we can just see it's effect, and if using the flow of water as an analogy to better get the theory across, so be it.

  • Flâneur
    Flâneurวันที่ผ่านมา

    I wasn't taught any of those 'lies'. People make those assumptions as they can relate to how plumbing works.

  • Daniel Kelley
    Daniel Kelley9 วันที่ผ่านมา

    If you added another bulb to the circuit, placing it as far away from the switch (in this case the moon), which bulb would turn on first?

  • Alekseev
    Alekseev10 วันที่ผ่านมา

    Hm, interesting.. so how do low temperatures and superconductivity (meant to reduce the Brownian motion / resistance in a metal wire) come into play?

  • Dalnore
    Dalnore2 หลายเดือนก่อน

    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

    หลายเดือนก่อน

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

  • Fourth Root

    Fourth Root

    หลายเดือนก่อน

    @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

    หลายเดือนก่อน

    @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.

  • Dalnore

    Dalnore

    หลายเดือนก่อน

    @Fourth Root it's (1 m)/c

  • Fourth Root

    Fourth Root

    หลายเดือนก่อน

    1/c seconds and 1/c are both obviously wrong because the units are wrong.

  • ed nja
    ed nja18 ชั่วโมงที่ผ่านมา

    If the wires in your circuit go all the way from one end of the USA to the other and back, there would be so much resistance that probably all the voltage would be dropped in the wire and the bulb won't light up. The electrons do flow through the wire, but very slow if there's a lot of resistance. If the resistance is close to zero, such as if the battery is shorted out, then the electrons flow much faster. What goes on in the wires is important. Also, even though the electrons move slow, all of the free electrons in the entire wire are moving. As some electrons leave the negative terminal of the battery, some different electrons flow into the positive terminal. This effect is at the speed of light, even though the electrons don't flow at the speed of light.

  • Sungenix Energy
    Sungenix Energy15 วันที่ผ่านมา

    The example about the failure of the undersea telegraph cables due to the iron sheath made me understand (sorta) why for example 3 phase conductors should not be separated into individual metal conduits by each phase. We actually had to repair an electrical installation in which the original contractor did this and it caused overheating and melting of the conductors.

  • Sungenix Energy

    Sungenix Energy

    15 วันที่ผ่านมา

    The conductors were 300MCM in 3" conduit so it wasn't a handyman's work hehe.

  • Jaydream T

    Jaydream T

    15 วันที่ผ่านมา

    @Sungenix Energy i can see that being a issue because who has a balanced phased system usally with 3 phase you have single phase loads aswell ..overall I know the handy man was trying lol

  • Sungenix Energy

    Sungenix Energy

    15 วันที่ผ่านมา

    @Jaydream T No the installation consisted of large conductors in parallel (3 sets of Phase A, B, C, N, & G). This would require 3 large conduits for each set of conductors. Installer decided however to separate the phases and put Phase A conductors in one conduit, B in another conduit, and so on. This is what caused the problem.

  • Jaydream T

    Jaydream T

    15 วันที่ผ่านมา

    Interesting a siingle conductor in a pipe can overheat ,I kinda took it as why we usually thru a neautral in the conduit but in 3 phase application ive ony seen it in a single condiuit ..suppose the installer didnt want to do the required pipe for 3 ? A good idea but proved wrong ...

  • Física o algo por el estilo
    Física o algo por el estilo5 วันที่ผ่านมา

    English is not my native language, please excuse me if I express myself wrong. Everything that has been said seems very enlightening to me, I think that even science students don't receive an adequated explaination of this concept. I also like that Muller is so honest and clarifies that often he himself have explained it badly. But he corrects it by making this video. It is an example that we can all continue to learn and understand even the topics that seem most basic. My only observation is that 1 / c * s does not have units of time, the correct expresion would be 1 / c * m (distance between source and lamp divided by wave propagation speed).

  • Sociedad del Bienestar Mutuo, SBM

    Sociedad del Bienestar Mutuo, SBM

    2 วันที่ผ่านมา

    Yes, the wire just work as a primer everyone in the alternate (not main street) physics know it, but the response to the next question can destroy all quantum physics. What is the medium that let the propagation of the electromagnetic fields?

  • Andrew Helmich
    Andrew Helmich10 วันที่ผ่านมา

    I really want to agree, I have one question though, since the principals of electricity stay the same in distribution and actually being used, how an incandescent light bulb heats up, what causes that actual heat? what is the magnetic field interacting with in order to create physical heat and light?

  • Paul Paul

    Paul Paul

    7 วันที่ผ่านมา

    There would need to be a mechanism which causes a piece of carbon for example to convert an electro magnetic field to heat.

  • Diego Savic

    Diego Savic

    8 วันที่ผ่านมา

    So i'm not sure i will be clear but will try to explained you something, the electromagnetic energy come with interact with electron (not completly that) , when a electron hit a résistance (electron are "order" of energy with slightly different frequency in 4 dimension and every wave create friction) they will create a force and then a mouvement (transformation on the wave cause of rebound of this one) Now, normaly because of "isolating" Material nothing happend cause the frequency is too different to create a movment but in the case of metal and conducting one what happend is that thr wave try to synchronise themeselve together creating a mouvement and movement is equal of increasing tempereture and then come another wave of another frequency : light Not sure i was clear XD hope so

  • Sam Gralla
    Sam Gralla2 หลายเดือนก่อน

    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

    2 หลายเดือนก่อน

    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

    2 หลายเดือนก่อน

    @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

    2 หลายเดือนก่อน

    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

    2 หลายเดือนก่อน

    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

    2 หลายเดือนก่อน

    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

  • Schlog1
    Schlog13 วันที่ผ่านมา

    Does the explanation in the video hold for incandescent bulbs? I was (perhaps wrongly) taught that filaments glow from the heat created by the resistance in the conducting filament to the movement of electrons in the circuit. Is this true, or are incandescent filaments somehow heated instead by the flux in the EM fields around the circuit? Or are these the same phenomenon!?! Electrical resistance is actually just the molecules in the conductor being exposed to the current-induced EM flux/photons, increasing their velocity/temperature?

  • MajorAstroPants
    MajorAstroPants10 วันที่ผ่านมา

    Does it take the same amount of time to turn on the light in the same circuit length if the battery and the bulb are at the maximum distance apart or does this only work if they are only 1m apart? Or am I totally misunderstanding this?

  • J Valentine
    J Valentine3 วันที่ผ่านมา

    It's my understanding that the electromagnetic field is along the outside of the wires . That's why litz wire made up of multiple strands carries more current than the same diameter of wire of a single strand . It's the square area of the conducting surface that carries the current . That's why cables are quoted as being so many millimetres square denoting their amperage carrying ability .

  • -Zach-
    -Zach-วันที่ผ่านมา

    So if the negative and positive wires were separated, would it still flow. Ex: a battery/power source on the east side of a city and the device it’s powering on the west side with the positive wire circling the city to the south and the negative wire circling the city to the north. In this example the wires are too far apart for the magnetic fields to connect? Would this prevent flow or am I missing the boat here?

  • Dito Alfrido
    Dito Alfridoหลายเดือนก่อน

    let assume i understand this entirely and asking to continue the next chapter about uncovering structure of every known subatomic particles or elementary particle to know what they made-off and what they work for, like: photons, electron, nucleus, graviton, gluon, quarks, orbital electron, higgs boson, hadron particles, electromagnetic, etc. iam completely curious to understand this and like how you explain this type of subject

  • Foodie Girl aka Skater Girl

    Foodie Girl aka Skater Girl

    หลายเดือนก่อน

    @10th House Tek I want to know where potential energy is stored.

  • Foodie Girl aka Skater Girl

    Foodie Girl aka Skater Girl

    หลายเดือนก่อน

    @rooks I want to learn about it bcs physics also "the rest is complex theory that requires advanced physics knowledge to grasp." again- yeah- physics...you are assuming that 99% of the ppl here arent giant nerds?

  • Dito Alfrido

    Dito Alfrido

    หลายเดือนก่อน

    @Pariv Doshi i think we never really get the entire lessons, just a bit information that enough make us impressed. at least not in this planet. somewhere, a place like library in heaven

  • elvancor

    elvancor

    หลายเดือนก่อน

    @10th House Tek What I meant was that currently, best we can do is statements like "An electron is that to which we attribute the properties of an electron". Eventually, things just stop being made out of tinier things. The term "elementary" alludes to that. In my personal opinion though, it's very possible that there are things about the universe that a human brain is structurally inherently incapable of grasping, just like any other animal has its cognitive limits. I think no matter how much information we collect, some dots we won't ever connect.

  • 10th House Tek

    10th House Tek

    หลายเดือนก่อน

    @elvancor are we even mentally prepared for those answers? The true nature of reality.

  • Jordan Appleseed
    Jordan Appleseed6 วันที่ผ่านมา

    So can you improve the efficiency of the battery by placing it in a position relative to the lightbulb that would generate well shaped field?

  • J Modified

    J Modified

    5 วันที่ผ่านมา

    Assuming an isolated system, the energy is going to end up in the bulb eventually. If you maximize the (tiny) amount it gets directly from the initial pulse, you are taking away from what it gets when that pulse reaches it through the wire.

  • S Underwood
    S Underwood7 วันที่ผ่านมา

    I worked in the commercial electrical trade and had my drivers license and bank card in my shirt pocket after lunch! We were pulling wire into a huge transfer station that was booted at the time ! The magnetic strips had been erased ! Can you explain how this happens ! How these fields flow around humans without harming them?

  • Walt P
    Walt P6 วันที่ผ่านมา

    I would have guessed 1 second. I seem to remember being taught many years ago that electricity "travels" at the speed of light.

  • ekhaat

    ekhaat

    5 วันที่ผ่านมา

    Well, sort of. The speed of light in copper is not the same as the speed of light in vacuum. And I would rephrase 'electricity "travels" at the speed of light' to 'potential energy propagates at the speed of light in the given medium'. Imagine you have the long wire not connected to anything, and when you connect the one pole of a battery, you measure the potential difference between the other end of the wire and the other pole of the battery, which are not connected, so no electrons flow. So the question would be: how long would it take for the potential difference to reach the other end of the wire.

  • dizekat
    dizekat7 วันที่ผ่านมา

    Fun fact: boards in computers contain a number of traces (wires) that meander back and forth to add extra delay and match the delay of other traces (whose start and end points may be further apart). The way this works is that the field is much stronger near the wire (and between the part of the wire that was already reached by the wave and the part that wasn't), and most of the field required to actually turn on something like an actual light bulb, does have to travel along the wire. Yeah, some of the field will reach nearby wires without having to go all the way around, but not to the extent to actually turn an actual light bulb on to full brightness, from 1 meter away, with a 12V battery; you'd need high voltage high frequency AC for that, like with a Tesla coil.

  • Mihail Dumitrescu
    Mihail Dumitrescu2 หลายเดือนก่อน

    Derek is somewhat right about the time being roughly 1m/c for the bulb to light up but only because the parameters of the problem were picked to be tricky (sometimes fun and educative). Unfortunately Derek doesn't go into details in the video and only says that the bulb "won't receive the entire voltage of the battery immediately". This may mislead you into thinking that the signal speed in an electric circuit depends not on the length of wires but on the air distance to the switch, which is wrong. The signal speed in wires is roughly 50-95% of the speed of light and most often is what dictates how long it takes for something to turn on in most circuits. This is why, for example, matching copper trace lengths in PCBs is often important. Or why high frequency trading companies care about their internet cable lengths. HOWEVER, often in circuits there's significant wireless EM radiation, intentional (radio, wifi, microwave) or unintentional (reduced with EM shielding). Turns out that in Derek's circuit one side of the wire initially acts roughly like an antenna while the other acts like a receiver and the power transmitted could be enough to light up an LED bulb. At 100m it wouldn't.

  • Nova

    Nova

    หลายเดือนก่อน

    @PCRetroProgrammer Causality isn't violated. You're just mistaken. Quite the personal incredulity. I don't know where you got the "MOST" when he did state in the video that it's only a fraction.

  • Fourth Root

    Fourth Root

    หลายเดือนก่อน

    Thank god I'm not the only person who noticed the unit error. "1/c seconds" is not a unit of time. "1m/c" is. Come on people, this is basic arithmetic.

  • Kuba

    Kuba

    หลายเดือนก่อน

    @Vawke Net Explain why. We are waiting.

  • nvmffs

    nvmffs

    หลายเดือนก่อน

    @Vawke Net And 12 people liked it

  • Vawke Net

    Vawke Net

    หลายเดือนก่อน

    @Kuba This has to be the dumbest comment I have ever seen.

  • Accutronitis The 2nd
    Accutronitis The 2nd3 วันที่ผ่านมา

    My answer is both "B" and "D" together, a small amount of energy will reach the light in 1/c seconds, but you'll have to wait the full 1 second for most of the energy to get there, so none of the five choices you have given...

  • David Clarkson
    David Clarkson13 วันที่ผ่านมา

    I was taught this very conceptincludind the right and left hand rule. If electricity flowed through the conductor (wire) then inductance and resonate frequencies in coils nor transformers would work; whether you're stepping up, or stepping down.

  • Devansh Sharma
    Devansh Sharma2 วันที่ผ่านมา

    Alright alright, putting my answer here before hearing yours as you asked. Its something I think about often but not long enough. So you made me think for two minutes straight. Current flow is essentially electromagnetic energy transfer and light is also electromagnetic energy. Then light travels at "c" in empty space, but slower in a medium, like water. So for electricity to run in a metallic wire, I'm guessing it should take longer. So it should be more than two seconds.

  • happysolar
    happysolar15 วันที่ผ่านมา

    Imaging if I place a switch on the circuit and place it 1 light second away. As claimed in this video, the light will turn on in 1/c second, if the switch is ON. This means that I can know the status of the switch almost instantaneously, or the information of the switch status travels to me faster than light, which is impossible according to the theory of relativity. Thought I do not know the exact answer, I think the lower limit of the time it takes to light up the bulb should be s/c, where s is the distance between the bulb and the farthest point of the circuit (in space).

  • soerenkoehler

    soerenkoehler

    14 วันที่ผ่านมา

    @Kanglar The antenna explanation sounds reasonable. But the answer D in the clip then has wrong units. "D) 1/c s" is rubbish because c has unit m/s. Then "1/c s" would be 1/(300000 m/s) * 1s = (1 s*s)/(300000 m) = 1/300000 s*s/m. Using your antenna explanation, answer D should be written as (1 m)/c = (1 m)/(300000 m/s) = (1 m*s)/(300000 m) = 1/300000 s which answer D probably was meant to be. @Veritasium: I was told in school to always and carefully track the units. ;-)

  • Kanglar

    Kanglar

    14 วันที่ผ่านมา

    This is not the case. The circuit could be open on the ends and would act exactly the same for the first 1/2 second. At the transient it is basically just 2 antennas 1 meter apart, the fact of it being a completed circuit or not is irrelevant to the bulb receiving some power within the first few nanoseconds. You would still only get the information whether the second switch is open or closed at the speed of light and no faster.

  • TechPassion
    TechPassion2 หลายเดือนก่อน

    I think the best part of this video isn't just the information it presents, but also the conversation it sparks in the comments! People asking questions, people trying to understand what's being said, and even people providing counter-arguments in certain scenarios where what Derek explains doesn't seem to match up. I think having civil discussions helps a ton, thanks Derek + the Veritasium community! This video and the comment section is genuinely interesting to go through

  • markmd9

    markmd9

    2 หลายเดือนก่อน

    @zekicay let's expand the experiment a bit, Let's say that the distance is not to the moon but to About Mars 30 minutes. You have a 12v battery, super conducted wire (no resistance - no loss in voltage) and 12v 💡. Can you please tell me what voltage will you have after 1/c seconds for the light to shine? Because 12v will come only after half an hour if there is no break in the line somewhere near Mars.

  • Colton Young

    Colton Young

    2 หลายเดือนก่อน

    Agreed. The intense amount of focus required for me to keep up is well worth the payoff of learning what you have to teach. You truly have such a unique mind and brain suited toward learning, curiousity, teaching, and excitement. Legitimately thank you for all you do Derek. Words can describe so much our appreciation for you. Sagan-esque as far as science educators go imho. Thank you for being you!

  • zekicay

    zekicay

    2 หลายเดือนก่อน

    @markmd9 He is partially correct and partially wrong. There will be some small energy transfer between the bulb and the battery in 1/c but the bulk will happen after more than 1s.

  • Billy Jones

    Billy Jones

    2 หลายเดือนก่อน

    I'm wondering if you even watched the video before you posted this self-aggrandizing waste.

  • Kanglar

    Kanglar

    2 หลายเดือนก่อน

    I think he is being somewhat intentionally deceptive/vague in the video on purpose to cause this :P He's not wrong, it's just a weird perspective.

  • A.M.M.E Education
    A.M.M.E Education3 วันที่ผ่านมา

    I have noticed that on many occasions in your explanation you have used the word electric charge and energy, but you didn't explain what the electric charge or energy itself is. If you kindly elaborate on the difference between electron and charge i think doing so you will come to a valid conclusion Thanks

  • Traveling Carpenter
    Traveling Carpenter15 วันที่ผ่านมา

    0:55 The first thing I remember at this point is this example one physics teacher once showed us. It was a pipe filled with glass balls. He told us that the electrons didn’t flow from one side lto the other with the speed of light, but what actually happened was that if you push one electron in, another comes out at the same time. So he pushed one ball on one side and another ball came out of the other side. So I guess I would go for D?

  • Traveling Carpenter

    Traveling Carpenter

    14 วันที่ผ่านมา

    @Scotty Boman Yeah I guess that’s true, so it lead me to the right answer but with complete wrong reasoning haha. The video amazed me. I never knew. It was always something that stuck with me because it would indeed imply that electricity would travel faster than the speed of light (instantaneously). Of course not entirely concerning the glass balls because the one pushing in isn’t the same as the one that comes out. I guess the only explanation would be that the energy is in the electrons, making the wire an energy source. Ha, never thought of it. With a bit of logic I could have figured it out myself, but I always thought, must have misinterpreted that lesson. Guess I did after all :P

  • Scotty Boman

    Scotty Boman

    15 วันที่ผ่านมา

    Except that reasoning would apply even if the light was 1 light second (instead of 1 meter away). That would violate relativity. I have used a similar model describing AC to my students, but the information (even from pushing a large solid object) can't go end-to-end faster than light.

  • Justin Melberg
    Justin Melberg2 วันที่ผ่านมา

    How does this relate to humans coming into contact with electricity. I've watched the electric companies drop humans onto a transmission line with a helicopter and I've seen the effects of electrocution through the human body, coursing inside the body through the nerves but I've never come to understand the how or why

  • shaamao
    shaamao8 วันที่ผ่านมา

    I know the energy is traveling through the electric and magnatic field. But the electic field can be neglected at several mm away. And in this case we are talking about 1 m. I won't say it will light up in 1/c. There might be a tiny little bif of current go through the bulb, like 0.000001% of what it should be, which would always be there even without the wire.

  • giovannipu
    giovannipuหลายเดือนก่อน

    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.

  • Ersin Emre

    Ersin Emre

    20 ชั่วโมงที่ผ่านมา

    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.

  • Reese

    Reese

    9 วันที่ผ่านมา

    2022 is your year, 📣 _"Make sure the money works for you,"_ *🔍 BLACKPINK Lisa - MONEY* 🎵 : Hip-Hop 🎵to get energy

  • MajinBuXL

    MajinBuXL

    22 วันที่ผ่านมา

    Derek is correct but in large part to the assumptions he is making. The lines having no resistance and also the light bulb turning on immediately when any amount of current is present are both really big assumptions. Technically if the bulb can turn on with any amount of current then it really doesn't matter what the circuit looks like because the bulb is always going to be on no matter what, even if its sitting by itself. There is always some free flow of electrons and the presence their magnetic field even in open air. I think the deeper point Derek is making is that it takes BOTH an electric field and a magnetic field to move the energy. Also the notion that electrons are "moving" along the wire is incorrect.

  • Joshua Little

    Joshua Little

    25 วันที่ผ่านมา

    I'm just a lay person but this would seem to explain how EMPs shut down electricity. Its not just that they fry circuitry which I'm sure they do that as well but they also disrupt the fields as well correct me if I'm wrong. I'm really just guessing but it makes sense to me.

  • cskesler

    cskesler

    หลายเดือนก่อน

    @Dave M Yes. Exactly. If I'm understanding this correctly, this really is a basic inductance question.

  • Sigman Floyd
    Sigman Floyd2 วันที่ผ่านมา

    ~ Is this why you hear a buzzing sound when standing under or near a voltage power lines? Also, how did they overcome the distortion when laying new cables on the ocean's floor?

  • steven Limbach
    steven Limbach14 วันที่ผ่านมา

    OK I thought I knew something about electricity and electrons, but now I'm completely confused!! Can you give this video another try ? My simple understanding was that electrons essentially "pushed" on the electrons next to them and moving electrons from one atom to another without necessarily forcing them to skip to other "shells" in the process. electrons can also " jump" to another orbit, which when they fall back can release energy in the form of photons.. ??????

  • Jeremy Bradley
    Jeremy Bradley14 วันที่ผ่านมา

    A small amount of energy from the battery makes it to the closely positioned bulb but only in an incidental way. The bulb is close enough to the battery that the EM wave generated by the current in the wire closest to the battery can reach it and create a current in the wire closest to the bulb. The same effect is present regardless of if the bulb is connected to the same circuit as the battery. This is straight forward induction. The way you frame this video you imply (to the laymen you are trying to reach) that the wires are not involved in the energy transfer at all. I know this is not what you are trying to say, but the way you present the information does make that implication. In reality the bulb will not light instantly, because that incidental induction is not nearly enough power to light the bulb (though you could contrive a scenario where you could light a bulb that way). Since nothing, not even energy, can travel faster than light the bulb will not light for at least 1 second (actually longer as the EM wave does not travel at c) as the EM wave travels along the circuit to reach the bulb.

  • Peter Heckert
    Peter Heckert6 ชั่วโมงที่ผ่านมา

    Consider a superconductive wire with diameter almost zero. Its inductance will be almost infinite and no current will flow.

  • Thomas Henderson
    Thomas Henderson2 หลายเดือนก่อน

    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

    2 หลายเดือนก่อน

    @flawn And that's cool. 👍🏻

  • flawn

    flawn

    2 หลายเดือนก่อน

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

  • Thomas Henderson

    Thomas Henderson

    2 หลายเดือนก่อน

    @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

    2 หลายเดือนก่อน

    @flawn No one said it was.

  • flawn

    flawn

    2 หลายเดือนก่อน

    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

  • Aldoran Weatherlight
    Aldoran Weatherlight14 วันที่ผ่านมา

    OK, let's look at the flux then. Can you stop this energy reaching it's destination without breaking the circuit? Can you cross the flux with a 2nd identical circuit with a 2nd light bulb and they kinda cancel out the flow the two circuits powers each light bulbs? Also, if you block the energy flux somehow can you still have a currency within the cables? Well, I like the idea that energy flow around and outside the cable. That kinda explains the people that complains about electrical allergy. I'm no expert in electricity, but I find it very cool that you with a short video can make a person like me understand electricity a bit more. Good work and keep posting more wonders like this. awesome!

  • Kevin Finnegan
    Kevin Finnegan11 วันที่ผ่านมา

    My pick was B. Choices A-C were measured in time and answer the question "how long will it take". Choice D is 1/c seconds. What is that? seconds per meter-seconds? It's almost as if you meant to say "the distance of your wire divided by c" Which is what I believed and why I chose B. A field flows in both directions along the wire meeting the bulb at 1 second. But I was thinking it would be equivalent to a circle circuit. I should have known since you threw in the seemingly trivial 1m wide dimension. Very tricky!

  • Spitler
    Spitler14 วันที่ผ่านมา

    would love to see the experiment worked out :)

  • Armon
    Armon14 วันที่ผ่านมา

    To prove your theory can you make a model and somehow disrupt the magnetic field around the wire and see if the bulb or load still works?

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