I am happy to see that many of us share the same channels to watch. For me, this one and ElectroBOOM are the two most virtuous ones, though each one with it´s specific way :D
They could do that at the very end of the video (6:23), and cover it with an endscreen card. This way, the face could be seen only under special circumstances (such as a minimised player) and it would become an Easter egg. Unlikely for a channel that aims for such a credibility level, though.
Oh my God, why do you upload at the right moment? I have so many questions in physics especially in electricity. This particular topic is one. You've cleared many of my questions since I'm 12 hahaha. I want to thank you for giving me huge intuitions about these subjects. I hope I could ask specific questions to you or at least you read it because I appreciate your work so much I would pay you if I could. You have the best type of content for people like me. I love u!!
I am glad my video helped answer your questions. Yes, please feel free to ask specific questions. It is best to post it as a new comment, as opposed to replying to an existing comment. This is because I am more likely to see new comments than I am to see a reply to a previous comment (There are problems with RU-vid's system for notifying me about comments posted). Thanks.
Eugene, I have to say, you have an amazing spirit and brilliant mind. My hometown is Houston, and I was there during the mass layoffs. It was a tough time for engineers, I remember it well. I myself ended up in Boston. You made the most of your time to help other people learn and that is great. You became an artist yourself. Much love from TX
This is an excellent video explaining the doubt which I had when I studied Ohm's law for the first time at school. However, my doubt went unanswered then and was dubbed a foolish question. But, I was able to figure it out myself. I am happy that I found this video and was able to validate my answer. Thank you so much.
I consider your chanle as the best reference for physics and I hope to see one day a video you do on E8 and its relation to partical physics because your explanation is always clear and simple and short
In my first year of college, when we were learning about semi-conductors, I asked a similar question based on the circuit we were looking at. Not in the same terms, but quite similar what you're describing here. The teacher decided to yell at me for wasting everyone's time, and I never bothered to raise my hand in that class again. Finding the answer on RU-vid almost 13 years later is a little weird, but feels like closure to something that stuck with me over the years :) Thanks a lot for all the work you put into your videos!
That was a horrible teacher. This teacher probably got upset because he didn't know the answer, and didn't want to admit it. Glad my video was able to provide closure. Thanks for the compliments.
They are expected to bring me knowledge. But , in an unexplainable way, they also bring me peace. Thanks for the first but my gratitude for the second is even bigger.
Veeeery goood job!! Really qualitative videos. And you really helped me to understand tensors. Don’t stop! Your videos help many people to become more close to science!! 💥💥🎊🎉🎊
There is an answer for superconducting cells and wires: inductance. Any circuit is a loop; any loop has inductance. You can have a continuous (DC) voltage across the inductance, but remember the current will always ramp up. The energy from the cell is stored in the inductance. This is how the coils in MRI scanners are charged up. After the charge voltage is removed and the coil shorted, the current flow can last forever so long as the wire does not lose superconductivity.
Actually, even our superconductors that we use at the LHC aren't ideal, but their resistance is still very, very, very small. Or at least I thought that before I watched this excellent video!
Something I don't find many people understand is only negitive electrons move, and all circut diagrams depict the opisite, I would love to learn more about this and how it efects real world electronics when creating modern circuts, it must become an issue eventualy.
Also, why do the 2 different voltage source has a current in it flowing? Is it right if I made the other one larger voltage, the current flow would be opposite?
So internal resistance of the battery has got it's practical significance even though if we neglect it in solving problems related to electrical circuits.
If you have a real-world battery (one with internal resistance) and you short the terminals and measure the current, you will get the same exact current if you put two of these batteries (perfectly identical to one another) in series with each other and repeat the experiment, because both the voltage and the resistance are both doubled. I mean, don't do that, but I think it's interesting. In a "typical" circuit, where the battery's internal resistance is negligible to the performance of the circuit, you would usually get a very different outcome when doubling the power source in series. At the same time, you'd get almost no difference (except a longer battery life) if you double the power source in parallel. But as you approach the maximum output current for the power source, this behavior flips.
Interesting. If/when a superconducting battery exists, infinite current, with no danger as no resistance means no heating. Intriguing implications for portable magnetic devices for a start?
You can make a voltage source with a transformer. For example you can alternate a magnetic field through a loop of superconductor. If you increase the magnetic field linearly, it will create a constant voltage. I’m not sure if the impedance of the self induction would be 0 since the voltage can be DC. I don’t know what would happen in that case… Btw great video!
Current in the coil will be created so as to perfectly cancel out the magnetic field, so that the net magnetic field is always zero. Hence the voltage is zero. Thanks for the compliment about my video.
there is another paradox, when you pulse a battery for the first time, you actually sometimes can get strong current limiting (high ESR), that is due to the oxidation of conductors being punctured by currents.. common with AA batteries, its a paradox because its not supposed to be here according to marketing. I am sure that girl is just studying before a Halloween midterm, and does not have a person as a DUT in mind.
This makes sense but couldn't you make a kind of pseudo-battery by inducing a current into a superconducting loop? Such a battery would have practically zero resistance. If such a battery were shorted by another superconductor (assuming connections between them could be made without added resistance) would current still flow across the short? Even an extremely small resistor put in parallel with another will decrease the total resistance across them both right?
At 3:30 you used a word internal resistance and you showed it outside the voltage source. Shouldn't an internal resistance be shown inside the voltage source between the two terminals? The source of internal resistance is basically the electrolyte present in the batteries. So why we model INTERNAL resistance as a resistor EXTERNAL to the voltage source ??
The actual terminal of the battery is after the resistor. We are modelling the battery as an ideal voltage source in series with a resistor, which give the correct mathematical results.
@@EugeneKhutoryansky as far as I understood from you reply is that we are considering the real battery to be ideal battery and and external resistor combined with it. And a real battery is same as ideal battery with a resistor external to it. But I mean to say can we instead consider the resistor to be inside the voltage source . If we do it how would it look like? Why don't you make a video on internal resistance in detail so we can understand this concept more deeply . In your video you discussed the big battery charging the smaller battery. So I want to ask how to charge the smaller battery faster? By increasing its internal resistance or by decreasing its internal resistance?
About superconductors: can they really have zero resistance? Wouldn't something related to Heisenberg uncertainty principle kick in like when trying to get absolute temperature of 0 K?
maybe you should do a video on..., for a better term... "impedance matching"? its very very closely related! this internal resistance versus circuit resistance. its like... if you go back to the basic of an eddy current brake, or the lenz reaction trick of a magnet in a copper pipe. the energy of it falling is dissipated in heat in the copper pipe as I2R. you cut a slot in the pipe, and now theres no eddy current and no reaction. you start adding resistance to the slot, and as it reduces, the heat starts to predominately appear across the resistance, until you reach a point that its the same resistance as the original material... at which point, heat is again distributed evenly through the entire mass of the conductor, and the "resistor". replace the pipe with thousands of turns of wire with two ends, and the same deal applies... the conductor has resistance, and the load resistance affects where the heat or the work, is predominately performed. you cant go lower than the winding resistance as it overloads... it generates the heat, does the "work", rather than the "load". alternatively, if the pipe is very thin, it will have a high resistance and cant generate much current, with less reaction, regardless of the input power pushing the magnet through it. when the winding resistance is so high it limits the current that can be delivered at that potential. a larger load, less resistance, simply lowers the voltage and less current flows. if the pipe is thick, it has a very low resistance. a certain amount of copper is just right for the speed the magnet moves,its flux density, the amount of "eddy current", the conductors resistance, the EMF induced and the current then seen... if one wants the maximum work done. as you make the pipe thicker and thicker, theres less and less resistance, and the magnet, or whatever is driving the magnet, sees more and more "reaction" to movement. you can drive a larger load, less resistance across the slotted pipe, with less heat generated in the conductor itself, but need proportionally more power pushing the magnet to do so. and that reaction is simultaneously trying to destroy the magnet by opposing it... a big generator can make a small current but a small generator cant make a big current. der. whats limiting the power? the supply, the generator, or the load? ignoring impedances and reactions. just DC resistance.
If everything is superconducting, the current will rise fast, but there is a counter induction voltage that limits the rise. If the superconducting battery is emptied, all energy is stored in the magnetic field of the circuit and the current runs forever.
The inductance limits the current only during the initial transient conditions. In steady state conditions, the inductance will not play a role in limiting the current.
@@EugeneKhutoryansky Steady state is only reached, when the battery is empty, if resistance is zero. This limits the current. If the inductivity of the circuit is constant, and the voltage is constant and the resistance is zero, the current will rise linearly, but *very* fast. This said, practical superconductors will break down, if the magnetic field is too strong, so the practical limit is lower. I am well aware, inductivity is not the subject of this video, just added this for completeness. I think your videos are excellent and I have recently learned a lot from them, love it!
There are at least a couple other factors limiting the real world outcomes of connecting a battery to a superconductor. Not only is there internal resistance in the battery but there is a limit to the rate at which the chemicals inside C battery can diffuse to free up electrons. There's also a limit to the number of charge carriers that exist in a superconductor so it ceases to become a superconductor above a certain current. Additionally there is a magnetic force limit on a superconductor that occurs because magnetic field can break up Cooper pairs that would normally carry easy electric charge. Finally electrons themselves have mass and require energy to accelerate them to higher and higher velocities as the current increases. Most of these effects are not problem low current but here were talking about current approaching Infinity
Mechalchik , your arguments are appreciable but the diffusion of chemicals inside a battery is a new point (information) for me . Can you please explain how this diffusion works inside a battery. Actually I have no idea about it. Is this tge diffusion of chemicals inside a battery that allows the battery to maintain a certain constant voltage between its terminals?
for a very brief moment during operation. A capacitor will act like an ideal voltage source. As long as the plates and terminals of the capacitor were to be made of superconductor, and the wires shorting were superconductor too. we would see what would happen.
@@fg8557 care to explain your reasoning? I clearly explained if my cap was made of superconductor the same as the short it should be valid. So I've eliminated the internal resistance. What did I miss?
This was a misconception I was facing from decades 😅 . Thanks a lot, my mentor ! This videos answers all the questions taking place in the mind of every good physics student. I have watched this video 2 times. 💚 . Now I have some queries. If something is gone wrong with RU-vid, should we comment on your facebook page posts in which you share your video's link? Will you make a video on Why power dissipation as heat in a wire or a resistor is directly proportional to current and not directly proportional to voltage? Why heat decreases with the increase of voltage and why heat increases as an increase of current? My mentor, the raduis of curvature formula in single variable calculus where y=f(x) is very very unintuitive an almost impossible to visualize. It is R=[(1+(dy/dx)²)³*½]/|d²x/dy²| R= (1+(dy/dx)²)³*½ _____________ |d²x/dy²| I hope you got it. So will you make a video on this topic. My mentor it is my humble request to make a video on energy levels in electricostatic and electrodynamic fields. In one of your videos you said that space time for negative charges is reversed as compared to space time for positive charges. Will you make a video on radio telescopes and the mysterious facts behind their resolution with their aperture size. This deserves a video and unfortunately no RU-vid video explains it intuitively. Will you make a video on how the universe actually looks when viewed from earth with the help of telescopes. Actually I am talking about the senerio in which we either have a Cartesian or spherical coordinate system and at the centre or origin we have earth. The center of earth consides with the center of the coordinate system. The line joining the poles and center of earth is parallel to z-axis in case of Cartesian coordinate system . It should be parallel to the equatorial plane in case of spherical coordinate system. Actually I am confused why only north and south poles are the best places for space observatories. Making this video is not an easy task but I am suggesting you about this because these is no such video on RU-vid and if you made this than your subscribers will rapidly increase. Will you make a video on Working theory behind Electrolysis (like the one you made on semiconductors) , Electrolytic batteries and Electrolytic cells ? Actually I am eager to know about the origins of internal resistance . When we searh on google, then google says that it is due to the presence of electrolyte . Electrolyte is mostly a liquid so I think before doing a video on internal resistance please make a detailed video on fluid mechanics and the concept of difference between fluid friction and fuild's viscosity. Also make a video on Newton's law of viscosity and visually demonstrate the most confusing, unexplained and ignored difference between dynamic and kinematic viscosity. Also please make a video on surface tension. Thanks a lot for reading this comment my mentor 😇 . I have been typing this comment for an hour. Please please please don't forget to reply to each and every question. I am very thankful to you. Again hats off for your great work. 😍
I hope to make videos on many of the topics that you mentioned. By the way, email is a much better way of reaching me than Facebook. As for RU-vid, the issue is that RU-vid often fails to notify me when a new comment has been posted. Thanks.
First, absolutely fantastic video! Second, a question. Every situation that I can think of that would create an ideal voltage is ultimately prohibited by the inductance of the wire itself. What would happen if you inverted the construction of the wire? For example, having the core of the wire be a non-conductive material (perhaps something like PTFE) and deposited the conductive material onto the nonconductive substrate? Additionally, would it be possible to introduce an external force (vibrations, for example) to counteract the inductance of the wire?
Значит, чтобы красные шары из одной батареи засунуть в другую, нужно, чтобы первая выдавала всегда большее напряжение? 🤔 Так получается, что ëмкость повербанков вообще не подходит для оценки способности отдать заряд.
Very interesting I was thinking on it while reading circuit theory, thanks for sharing knowledge. could you do a video on the spin of particles that why some have half spin and some have integral multiple need physical reason.
I watched your video on nuclear bombs and that was great. Well what if you make a video on asteroid strike (straight /orbital) and orbital kinetic strike (project Thor) . Please also tell us can army use an artificial planned guided asteroid attack on the enemy? If you made that video it would be great. 💚💚 These is very less and incomplete information (on RU-vid) about asteroid strikes and ways of maximizing the energy of explosion of asteroids of same size .
The magnet will induce a current so as to cancel out any magnetic fields inside the conductor. We can't have any voltage drops inside an ideal conductor.
I've read about batteries a while ago, and that ∆G = -nFE = -RT lnQ. I know this is just an ideal case, since ∆G represents the *maximum* amount of work the system can produce, which only happens at an equilibrium state, implying that the change must be quasi-static and the current flow must be kept at a minimum. My question is: why is the change in electrical potential proportional to the current flow (since E(real) = E(ideal) - Ri)? Is it just the first term of a taylor series expansion or is it actually linear? And if it's just an approximation, what is the actual formula that describes the voltage drop, and how do you derive it?
My mentor! There is one thing that I can't understand at all. I can easily understand that a superconductive wire section in a circuit is always at a same potential. But what I can't grasp at all is that why two ends of a resistor are not at same potential ? Would you please kindly answer me? 😘
Непонятно, зачем столько заморочек. Ведь ток в полной цепи не создаётся нулевым напряжением на нулевом сопротивлении. Закоротка в данном случае это просто участок цепи. Тут надо рассматривать формулу для полной цепи, где фигурирует ЭДС, внутреннее сопротивление и внешнее. Из них только внешнее R равно нулю, а ЭДС и внутреннее остались на месте. То есть имеем простейшую цепь с нулевым сопротивлением на выводах источника, и максимальный ток получается не за счёт нулевого напряжения на клеммах, а за счёт ЭДС, которая у батареи как была, так и осталась. Вот и нет парадокса.
