What is a Magnetic Field? (Electromagnetism - Physics)

[@photon434]

Complex concepts visualized. Magnetism is emergent -- so cool.

[@PhysicsMadeEasy]

Thank you for your kind comment! Yes Emergence is quite a common phenomena in physics (and quite fascinating must I say!). Other examples that come to mind immediately are temperature and mass.

[@combomaster99]

Something that keeps me thinking is how do magnets work in a vacuum. As there is some sort of static field emerging from a permanent magnet that does not consume any kind of power, does not need any kind matter to transfer energy from one pole to the other. Extreme strong magnets have large fields but are not detectable by any sort of visual camera yet are very much present. So much so that one could crush your hand if you held it between the magnet and a piece of iron or another magnet. This means its having a clear and strong effect radiating onto the fabric of space. But what exactly is that field made off. The only way you can know its there is by having something that interacts with it. As far as i understand your explanation of those fields are 'Electrical Phenomena'. Awesome video, sorry if i didn't fully understand it. I appreciate it immensely that you take the time and effort explaining such topics.

[@PhysicsMadeEasy]

Hi Combomaster, most of the answers are in the video, and your questions, which are good ones, show that you seem to have some misunderstanding about the concept of fields. You mention energy (power) not being consumed by a magnet or field. Yes. You can see a magnet like a mountain and a map of the height as the field itself. Place a ball on the mountains slope, it falls down the slope and gains velocity (Kinetic energy). The energy doesn’t come from the magnet or the field (the mountain or the height), but from the person that went up the mountain to put the ball there in the first place and gave that ball potential energy … Maybe check the video ‘what is a field?’, and then ‘what is an electric field?’. That could help. A field is not an object, so cannot be directly observed as such (like with a camera), only its effects on what is positioned in the field. Some actually think that fields are just an abstract mathematical tool useful to model the world around us (I am among them, but only as far as classical physics is concerned). You had good questions, well-constructed, that show Curiosity. Continue digging!

[@zBrush01]

Well explained to understand for a non Physicist as well. Thx 🖖

[@PhysicsMadeEasy]

That is a super comment, thanks! If in addition to help young students interested in physics, I can bring some understanding to non physicist, I just surpassed my objective!

[@ISHVVN09]

Wow, absolutely phenomenal. I'm in the tenth grade and for the past two years I have asked many, in fact all of my science teachers to explain the magnetic field, but they gave no answer at all. But you have made it so so simple. Amazing!

[@PhysicsMadeEasy]

Thank you so much for your kind feedback :-) I hope what you understood in this video will help you further in your studies of physics!

[@echo-eco]

Thank you so much. I understood magnetic properties with special relativity more than the classical equations.but as you said," just use them" is gold.❤

[@PhysicsMadeEasy]

Thanks for your comment echo. Trust is important in the learning process... or a student can easily get overwhelmed... And as he moves forward, things will clarify, and he will get answers...

[@daddyfrhuh]

Hello , professor glad you are still making videos for the community , your videos are so helpful that I cannot explain in words , Id just like to say please keep making physics easy and we will hit a milestone for sure ! Much loving and blessings ❤

[@PhysicsMadeEasy]

Thank you for your encouragements!

[@anamulhaque-dt3eu]

A magnetic field is an electric field that can only be seen when observed from a moving frame of reference! Even after doing a masters in electrical and electronics field I have got to know this thing today, thanks!

[@surendranmk5306]

@@anamulhaque-dt3eu It is just like uniform motion is un detectable. But acceleration is detectable. Only right when the fields are constant . Varying electric and magnetic fields are detectable from a relatively stationary frame of reference to those.

[@kub8675]

I’ve always struggled to understand what and why a magnetic field is. This really helped me get it, thanks!

[@PhysicsMadeEasy]

You are welcome Kub!

[@dumptruckmotorcade]

Easily the most mind-blowing video I've watched in years.

[@PhysicsMadeEasy]

Wow, thank you so much for this warm comment!

[@vorsybl]

Thanks for making another video! Many of the previous ones have helped me understand physics better (especially the ones on waves, which were very confusing for me at first....energy, and work).

[@PhysicsMadeEasy]

Thank you for kind your feedback vorsybl. I am glad my work brings you closer to understanding physics :-)

[@vincecox8376]

Please get tuned into facts, 1. anti gravity is a product of the center field of a magnet. 2. the center of a magnet when vibrated will repel water 3. If you vibrate granite rock with the center field of a magnet at the correct frequency it will turn like butter. that's just the beginning it will play a Hugh part of our country's future. This is only applicable to none iron type material such as glass or plastic. If you have a bar magnet simply tap the center near a trickle of water and watch the water move out of the way. Tap the center field on any none metalic surface and watch it loose weight. You can not use a sign wave type vibration it must be saw tooth . A sign wave signal contains the centerfield, that's what pushes AC and radio signals around the world. A sign wave has three elements on an oscilloscope you only see the two , On a scope you see the positive cycle and the negative cycle you never see the most significant part of the cycle and that is the center field that produces the energy to push the energy forward!!! There is allot to be learned about the magnetic center field .. Please help spred the news ..

[@profelu1919]

Coming again to really study your content taking notes. You rock!

[@PhysicsMadeEasy]

Hi Profelu, thank you very much for your feedback. I am glad I have such a fan regarding my electricity and magnetism videos ❤️

[@spencerwenzel7381]

I have wondered this for a while. Why does it matter that the positive charge, q+, moves relative to the positive charges in the wire? For example, if we were to keep q+ stationary with respect to the wire, the electrons would still move relative to q+ and therefore length contraction should still occur. In your example with the bicycle and the table, there were only two objects, you and the table. Why not with just the two objects, q+ and the electrons in the wire?

[@PhysicsMadeEasy]

Hello Spencer, Very good comment. While I was working on the script of the video, I asked myself a similar question : If the wire with no electron flow is neutral for a moving test charge, how come it is still neutral when a current is flowing. It is true that what I say in the video suggests otherwise. It didn’t stop me from posting because all other lectures and videos I saw on the topic didn’t seem to consider this question. Even Feynman, in his famous lectures, presents a special case, and just evades the question. I even asked chat gpt4, and it kept answering me in circle, haha ! I’ve been thinking about it, and I realised that the issue is that charge q+ is going much faster than the electrons : The emergence of magnetic effects become significant only for relativistic speeds of the test charge q+. Imagine you accelerate a proton (the test charge) in vacuum with a simple 9V battery. I calculated that the speed for a proton would be in the tens of thousands of m/s (roughly 42 km/s), and for an electron in the millions (roughly 1800 km/s). While the drift velocity of electrons in the wire electrons is tiny (a few mm per second). What actually counts is the difference of velocities perceived by the test charge between positive charges and negative charges in the cable. The effect of this tiny difference (= drift velocity) at small non-relativistic velocities is insignificant, but has a significant effect when the speed of the test charge becomes relativistic : At relativistic speeds, If you change the speed of the particle, that change will lead to a difference of length contraction for positive and negative charges that is significant. At low speeds, If you change the speed of the particle, that change will lead to a difference of length contraction for positive and negative charges that is so insignificant, that the cable can be considered as remaining neutral. The example on the video is more of a thought experiment, reality as it is, would have been very difficult to represent accurately in an animation… I should have discussed this in the video, but I believe this would have provided more confusion than clarity… (my videos are intended to provide the viewer with a first step towards a knowledge that they can then develop by themselves…). Best,

[@spencerwenzel7381]

@@PhysicsMadeEasy thank-you for the very detailed response. I haven't found a good explanation of this for years until your comment. It makes perfect sense now. Your ability to describe concepts clearly has been extremely useful to me in conveying similar concepts to my students. Really appreciate the work you put into making these 👍

[@cristig243]

​When you know it doesn't make physical sense, but you are still pushing it because of...einstein 👌​@@PhysicsMadeEasy

[@xyz-mt6iw]

Thanks a lot! I have understood now the idea behind how magnetic field is created, or rather what it really is infact.

[@PhysicsMadeEasy]

Thank you for your feedback. I am glad I was able to debunk this for you!

[@jakirshah1683]

You are awesome in putting complicated things in simplified way. Students may benefitted more as well others . Please keep it up

[@PhysicsMadeEasy]

Thank you Jakir. I do indeed try to Make Physics Easy :-)

[@silvermine2033]

Just the answer I was looking for. Thank you!!

[@PhysicsMadeEasy]

Top! I am glad my work helped :-)

[@omerkaya545]

3:09 In our example, at the level of charge little q, the magnetic field is going away from you: that is, "into the page". Several questions: What does "level" mean here? Why is charge q called "little", what does "little" imply? "Is going away from you" What do you mean by going away from me? What does "into the page" mean? What is the page?

[@PhysicsMadeEasy]

Hi Omer What does "level" mean here? It means at the position of little q (You know I am French right? In French we can say that - but I agree, it doesn't translate well in English - Lesson learned!) Why is charge q called "little", what does "little" imply? little q refers to the size of the letter. q is "little q" and usually represents a test charge. Q is "big Q", and usually the charge at the source of an electric field "Is going away from you" What do you mean by going away from me? What does "into the page" mean? What is the page? these expressions refer to the direction of a vector. For example the vector velocity can be directed to the right, to the left, up , down , but we live in a 3D world: the velocity vector could also be directed away from the observer or towards the observer. When you see a cross in a circle, that represents an arrow going away from you (you see the feathers of the arrow): it means you the viewer see the arrow going towards / into the screen (or into the page). Alternatively, the arrow could be going towards you, so it is going out of the screen (or out of the page). It is represented by a dot in a circle (you see the tip of the arrow pointing at you) I hope this helps!

[@jaspreetmodi]

the ending was really nice to continue using it

[@vaishakpraveen7093]

Sir i am from India and, Im poor in physics after watching your lectures i am understanding somehow Thankyou can you do gravitation videos

[@PhysicsMadeEasy]

Hi, I do not have many gravitation videos on the channel (Just 'why is gravitational energy always negative'). But I have produced a few years ago a full course on Gravity basics (where I start from the beginning). Check it out: www.udemy.com/course/gravity-the-basics/. It could help.

[@vincecox8376]

Please get tuned into facts, 1. anti gravity is a product of the center field of a magnet. 2. the center of a magnet when vibrated will repel water 3. If you vibrate granite rock with the center field of a magnet at the correct frequency it will turn like butter. that's just the beginning it will play a Hugh part of our country's future. This is only applicable to none iron type material such as glass or plastic. If you have a bar magnet simply tap the center near a trickle of water and watch the water move out of the way. Tap the center field on any none metalic surface and watch it loose weight. You can not use a sign wave type vibration it must be saw tooth . A sign wave signal contains the centerfield, that's what pushes AC and radio signals around the world. A sign wave has three elements on an oscilloscope you only see the two , On a scope you see the positive cycle and the negative cycle you never see the most significant part of the cycle and that is the center field that produces the energy to push the energy forward!!! There is allot to be learned about the magnetic center field .. Please help spred the news ..

[@midwestchau]

That was mind blowing. Seriously.

[@PhysicsMadeEasy]

@@midwestchau Thanks for your encouraging feedback!

[@unnikrishnanms3431]

Simple...Lucid...Mind blowing explanation

[@PhysicsMadeEasy]

Thank you so much for your encouraging words!

[@yuhannizar2857]

Good explanation, Thank you Sir

[@PhysicsMadeEasy]

You are welcome Yuhan

[@MR.LOCAL-X2]

Sir please post on electromagnetic induction and how it works

[@PhysicsMadeEasy]

Hi, we are getting there... As you might have noted, I am in a 'Electromagnetic mood' these days. The plan is to produce a few more videos: Magnetic monopoles, Faraday's and Lenz Law, and then I will conclude with a firework discussing EM induction in circuits... That's the plan, I hope time will allow me to do so! Up to now it has, so fingers crossed!

[@MR.LOCAL-X2]

@@PhysicsMadeEasy thankyou sir

[@anshsahu6204]

Superb explanation sir 💗, The channel always getting positive comments ❤❤❤❤

[@PhysicsMadeEasy]

Thanks again Anshsahu for your feedback. Yes, the comments I read in the morning usually make my day! They show that I am reaching my goal with this channel (helping high school students with their studies by providing them solid basics!)

[@roshanperera402]

Got a sound knowledge about magnetism.thanks lot.pls carry on these topics.

[@PhysicsMadeEasy]

Thank you for your kind comment Rosh! I did quite a bunch of videos on electromagnetism, and I still have one or two in mind... but these are not on top of the list... yet, I will probably enter another EM physics phase in the future so patience :-).

[@value_network]

Great one, such a helpful video

[@PhysicsMadeEasy]

Thank you Julien

[@cala416]

really good and intuitive explanation, thanks a lot.

[@PhysicsMadeEasy]

You are very much welcome Cala.

[@EnochBrown-s5j]

Wonderful again!!! Thank you, sir!!!

[@PhysicsMadeEasy]

You are warmly welcome!

[@funmylolarojo2589]

I have learned a lot from this. Thank you!

[@sunitasultan7456]

Keep making videos. You teach really good, sir.

[@PhysicsMadeEasy]

Thank you for your kind words Sunita!

[@starexplorers1202]

Magnetic fields emerge from an electric field feeding back in the opposite direction. This is why there are no monopoles. Standing waves "emerge" from traveling waves when two traveling waves of the same frequency, amplitude, and polarization superimpose and travel in opposite directions. This process is called interference and results in the wave energies either combining or canceling each other out. The resulting wave appears to stand still (i.e., magnetism), but it's actually made up of traveling waves that bounce back and forth.

[@drprofessorsoso208]

I extend my gratitude for your earnest endeavor to elucidate the nature of magnetic fields. However, I must assert that, in my estimation, our grasp of what magnetic fields *are* remains profoundly deficient. While we have succeeded in characterizing their behavior with admirable precision through a panoply of equations and models, the ontological essence of these enigmatic fields continues to elude our understanding. The classical framework, for instance, conceptualizes magnetic field lines not as entities endowed with intrinsic particulate substance-such as the atoms or subatomic particles that constitute matter-but as purely abstract constructs. These lines serve as an expedient heuristic, a visual and mathematical representation of the directionality and magnitude of magnetic influence within a given spatial domain. Their depiction illustrates the behavior of magnetic phenomena, such as the forces emanating from a magnet or electric current, but refrains from offering any substantive insight into their underlying nature. These field lines are devoid of tangible substance, existing instead as an abstraction employed to render the otherwise intangible dynamics of magnetic fields comprehensible. They elegantly represent the directional vector of magnetic force, radiating outward from the magnet's so-called "north pole" and looping back to its "south pole," thereby forming continuous closed loops. Within this framework, the density of the lines is indicative of the field's intensity: regions where the lines are densely clustered signify a stronger magnetic influence, whereas sparsely distributed lines suggest a diminished field strength. Yet, for all its utility in describing magnetic behavior, this classical interpretation falls conspicuously short of addressing the fundamental *substance* of the magnetic field itself. It invites us to ponder whether the magnetic field possesses an underlying particulate or quantum structure-or whether its essence lies in an entirely different domain of physical reality that our current conceptual frameworks are ill-equipped to grasp. In examining the nature of magnetic fields, I find that while our mathematical frameworks and experimental observations effectively describe their behavior, the fundamental essence of what magnetic fields *are* remains shrouded in mystery. The classical model, which uses magnetic field lines as a conceptual tool, offers valuable insight into how these forces behave but stops short of explaining their intrinsic substance or composition. Magnetic field lines, though essential for visualizing and predicting magnetic phenomena, are purely abstract constructs without physical substance. They cannot be measured or isolated as discrete components but instead represent the field's direction and strength around a magnet or current. This abstraction is instrumental in understanding behaviors such as attraction, repulsion, and flux, yet it does not address the deeper question of what generates the field itself. The classical visualization depicts magnetic field lines as emerging from a magnet's north pole, looping through space, and returning to the south pole before completing the circuit within the magnet. While this model effectively demonstrates the continuity and directional nature of magnetic fields, it sheds no light on the underlying mechanism or composition of these fields. Similarly, the density of field lines as an indicator of field strength-denser for stronger fields and sparser for weaker ones-remains a human-centric model of interpretation rather than a revelation of physical reality. Classical physics treats magnetic fields as emergent phenomena, arising from the movement of electric charges and the magnetic moments of particles like electrons. Maxwell's equations, while extraordinarily accurate in describing this emergent behavior, offer no explanation of the field's fundamental substance. Even quantum field theory, which views magnetic fields as part of the larger electromagnetic field governed by quantum electrodynamics, focuses on interactions and force carriers like photons rather than the ontological nature of magnetism itself. This leaves us in a position where we can effectively describe and harness magnetic phenomena but remain unable to define their true essence. The gap between behavior and being underscores the limitations of both classical and quantum frameworks and invites speculation that the ultimate nature of magnetic fields may lie beyond our current understanding, possibly within principles or dimensions yet to be discovered. This gives me an idea which leaves me with questions. The idea is directly harnessing magnetic field lines as a source of pure magnetic energy, without converting it into electricity, represents a revolutionary shift in energy utilization. Traditional energy systems rely on converting magnetic energy into electrical energy, often through mechanical processes like the rotation of turbines or the induction of electric currents. This new approach, however, envisions tapping into the inherent energy of magnetic fields themselves, treating them as a direct and usable energy source. In the current framework, magnetic field lines, typically regarded as abstract tools for visualizing magnetic forces, are reimagined as real carriers of energy. By interacting directly with these field lines, it may be possible to extract and utilize their embedded energy without the intermediary step of generating electricity. This approach calls for the development of advanced systems capable of engaging with magnetic flux in its raw form to harvest its energy directly. One potential method involves manipulating and concentrating magnetic flux. Techniques such as magnetic flux compression could confine field lines into smaller spaces, thereby intensifying their energy and making it more accessible. Another possibility lies in designing magnetic circuits capable of sustaining and amplifying magnetic energy flow, effectively creating a closed-loop system where energy is continuously maintained and utilized without conversion into electrical form. Specialized devices could be engineered to interact with magnetic fields, applying methods like flux trapping or compression to harness their intrinsic energy. These systems could power machinery, drive mechanical operations, or perform tasks using the raw properties of magnetic fields, bypassing the need for electrical transformation. Such devices would focus on capturing the energy stored within magnetic field lines and directly utilizing it in its original magnetic state. This concept opens up a realm of possibilities, suggesting that magnetic energy itself, rather than the electrical energy derived from it, could serve as a primary energy source. By circumventing conventional energy-generation methods-such as combustion, turbine rotation, or electrical conversion-this approach could pave the way for entirely new technologies and systems powered by the intrinsic properties of magnetic fields. If realized, it would mark a transformative advancement in the way energy is harnessed and utilized. My erudite colleague, I propose that we reexamine the prevailing paradigm regarding magnetic field lines, wherein magnetism is purportedly generated by the synergistic confluence of electrons' intrinsic spin, orbital angular momentum, and charge. Nevertheless, our extant models posit that magnetic field lines serve merely as abstract, heuristic devices, facilitating visualization of these fields, whereas, in reality, they constitute tangible, physical entities. The flaw in our current understanding lies in the oversimplification of magnetism's underlying mechanisms. The electron spin and orbital angular momentum model, though efficacious in certain contexts, fails to provide a comprehensive explication of magnetic field generation. Furthermore, the dichotomy between classical electromagnetism and quantum mechanics precipitates inconsistencies, rendering our present framework inadequate. Permit me to elucidate the specific lacunae in our current models: 1. *Reificational Inadequacy*: Magnetic field lines are reified as abstract constructs, rather than acknowledged as physical entities. 2. *Observational Incongruity*: The non-observability of magnetic field lines, in contradistinction to electric field lines, raises fundamental questions. 3. *Theoretical Incoherence*: The prevailing model struggles to provide a seamless integration with quantum mechanics. In light of these limitations, I suggest we reconsider alternative perspectives: 1. *Magnetic Field Lines as Physical Entities*: Reconceive magnetic field lines as tangible, physical structures. 2. *Quantum Vortex Dynamics*: Envision magnetic fields as comprising quantized vortices, analogous to fluid dynamics. 3. *Magnetic Monopole Theory*: Postulate the existence of magnetic monopoles, providing a more comprehensive understanding of magnetism. In conclusion, my esteemed colleague, I propose that we revisit the fundamental assumptions underlying our current models and explore alternative frameworks to rectify the existing lacunae.

[@PhysicsMadeEasy]

Hi, This was a long read. I had to skim some parts: so please forgive any misunderstanding my words might convey: I agree, the nature of magnetic fields is still not entirely understood, but neither is the true nature of an electron, nor the nature of space, and all other things that we perceive as reality. Physics is aimed at explaining how the universe works, not why it works that way… Maybe, one day, at the turn of a fundamental discovery, our paradigm will change, but for now, we just try to find patterns from observation, from these patterns, develop theories which predict other phenomena and then test these theories by verifying their predictions. A few comments that come to mind relatively to the lacunae of current models: 2: electric lines are abstract constructs too… the difference is the frame of reference of the observer. And yes we can observe magnetic field lines (just spray magnetic material powder on some non-frictionless paper placed in a magnetic field…) L3: yes, and in reference to what I suggested, this not only true for Magnetic fields, but for all (fundamental) physics… Oh, and regarding your proposition of magnetic only engine… (Magnetic Energy --> Mechanical Energy), well you need first to show that magnetism can be considered in total disconnection with electric charges… good luck with that 😉! Greetings, Edouard

[@liminal27]

This phenomenon occurs with an observer and a *single electric charge* moving in space - no wire, no protons. I would love to see an explanation of this case and how the Lorentz transformation on the field of a single charge causes the observer to see a magnetic field emerge.

[@andersemanuel]

This was your best! Thank you.

[@PhysicsMadeEasy]

Thank you Manuel :-)

[@bert9201]

Thank you! Really good content!

[@PhysicsMadeEasy]

Hello Bert, thank you for your feedback. I am glad you enjoy my work!

[@AutisticCuriosity]

You didn’t describe a magnetic field is, you described its behaviour. Like saying an apple is something that falls from a tree, and threw in some obvious maths about the falling apple to give it legitimacy.

[@PhysicsMadeEasy]

Hi, maybe you should watch the video more thoroughly. I clearly state what it is: it is how you see an electric field seen from an inertial frame of reference... It appears like a distinct phenomena, but it is just a facet of electric fields that emerges when considering relativistic physics. Now, please take my words with no absolute, I am using here a classical physics model... For example, in quantum mechanics, we observe the magnetic dipole moment of an electron, and we deduce from that that it is spinning (= it is a loop of current).... Chicken and the egg... Which one comes first? Watch my video on magnetic dipole moments (especially the very end part, where I discuss out of script this subject). So, you are right in a way, I cannot give you a definite, clear and absolute answer, but I can give you direction of thoughts that might trigger in you the will to participate in this fascinating quest that is Physics!

[@fridmamedov270]

3BLUE1BROWN, Dr. Trefor Bazett, You, are just amazing. Understanding is more important than the computation!

[@PhysicsMadeEasy]

Thank you Dr!

[@moshe789]

I'm sorry but you didn't explain what a magnet or magnetism is.

[@PhysicsMadeEasy]

Hi Moshe, I know, I explained what a magnetic field was... Not what a magnet was. A magnet is what generates a magnetic field or aligns with an external one. And what creates a magnetic field? Loops of currents. So, magnets are actually loops of urrents. If you truly want to understand what a magnet is check the video "what is a magnetic dipole moment": kzbin.info/www/bejne/oniUhYNrYtd-nK8. And what about permanent magnets (like those on your fridge)? These are materials where there is a bunch of electrons having magnetic dipole moments all parallel to each other (= having loops of currents all in the same plane, and for which the currents are all with the same direction). As for magnetism, it is a branch of physics that deals with magnetic fields and magnets.

[@waynemccuen8213]

So, we see in a 2 dimensional example a sine wave on a graph. Growing in a positive direction, then getting smaller and growing in a negative direction. In real time, it would be more like a ball growing positive then shrinking then turning inside out and reversing? I've never thought of this before! My mind is blown. I can't think this through! Thanks for confusing me on a higher level

[@PhysicsMadeEasy]

Hi Wayne, you are welcoming for confusing you on the highest level haha :-) I don't really get what you are referring too (What is the on the x and y axes of the sine graph you discuss?)

[@dalenassar9152]

This video brings to mind something that has had me puzzled from the start: "THAT 12 YEAR-LONG GAP BETWEEN THE DISCOVERY THAT CURRENT PRODUCES MAGNETIC FIELDS, UNTIL THE DISCOVERY THAT MAGNETIC FIELDS CAN PRODUCE CURRENTS" When the 1st discovery was announced, then, INSTANTLY, (as a Cal-Tech physicist put it), "all scientists immediately ran to their labs to prove the the reverse was also true. i.e. 'current can be made to flow by a mag. field'. Then 12 YEARS went by with no success!!. How can this be?? It should have the same day! They set up B-fields and their conducting wires connected to galvanometers and started working tirelessly, putting wires in B-fields while watching the current sensors. Although MOTION of the wire was required, there had to be moments where they moved the wires into the field....even if they placed the wires into the field space BEFORE turning on the current, the detector would have jumped. These work tables were 'covered' with all kinds of current sources, switches, coils, detectors, etc. Your thoughts?? Thanks for the great ..as usual..video! --dALE PS, one other thing: I have seen all the physics of forces on charges moving in B-fields...mostly charged particles and current-carrying wires...But I have been looking for details the physics of an energetic spark in a B-field. IOW: how the charges and currents in a spark channel differ compared to a current-carrying wire. I would wonder how the F=BIL equation would be written for a free arc. Your unique videos are VERY valuable, and probably inspire much further than realized--very unusual!!

[@nguttam1982]

Can explain how the permanent magnets work according to Special Theory of Relativity.

[@PhysicsMadeEasy]

The same way! An electron spins, left or right. An electron is also a ball of charge, so you get a loop of current... thus a magnetic field. if you have two electrons of opposite spins, they pair up and the two magnetic fields cancel. Magnetic materials are those which have a structure such as all electron spins cannot pair up.. Now this, what I wrote here is just a pure interpolation... As it is the magnetic field that is generated by an electron that makes us think that they spin... (reverse thinking). Check the video about magnetic dipole moment, especially the part at the very end of the video. I discuss this. kzbin.info/www/bejne/oniUhYNrYtd-nK8si=R9uNrWksaRPL_UzC

[@castrothg]

Amazing content thanks a lot for sharing it.

[@vincecox8376]

Please get tuned into facts, 1. anti gravity is a product of the center field of a magnet. 2. the center of a magnet when vibrated will repel water 3. If you vibrate granite rock with the center field of a magnet at the correct frequency it will turn like butter. that's just the beginning it will play a Hugh part of our country's future. This is only applicable to none iron type material such as glass or plastic. If you have a bar magnet simply tap the center near a trickle of water and watch the water move out of the way. Tap the center field on any none metalic surface and watch it loose weight. You can not use a sign wave type vibration it must be saw tooth . A sign wave signal contains the centerfield, that's what pushes AC and radio signals around the world. A sign wave has three elements on an oscilloscope you only see the two , On a scope you see the positive cycle and the negative cycle you never see the most significant part of the cycle and that is the center field that produces the energy to push the energy forward!!! There is allot to be learned about the magnetic center field .. Please help spred the news ..

[@manabouttown7865]

Can you give the same intuition about induction and back emf?

[@PhysicsMadeEasy]

That was the plan when I published this video and a few others (capacitance, Gauss law etc), but things are as they are, and I had to get back to (real) work before I could end this series. I'll probably come back to it one day :-)

[@mdnurainansari3414]

Hy!! Thanks for this video... I can now learn deeply about this Thanks again

[@PhysicsMadeEasy]

You are welcome. mdnurainansari. I hope you enjoy it!

[@aryaashok1633]

Professor, please post on displacement current ...

[@auseryt]

Because motion is relative and I'm special relativity one cannot distinguish who is moving you would see a moving object length contracting. Hence, even for an observer not moving relative to the cable the moving electrons contract and so do the moving gaps between them.

[@Paulfly]

Nice explanation! I don’t quite understand why the “d” between electrons is larger than the nominal “d0”, could you please explain more about it? Thank you professor.

[@PhysicsMadeEasy]

Hello Paul. because in the example, the observer is moving along with the electrons, so their relative velocity (= difference of velocities between electrons and observer) is less than at rest, thus the distance between electrons seen from the observer increases.

[@Paulfly]

Thank you professor. Given the test Q is static. Assuming no current flow thru the cable, the nominal distance between electrons is same as protons, which is d0. When the cable moves upward with V1 relative to test Q, from the test Q’ view, distance between electrons and protons becomes d1. When applied voltage, the electrons move downward with V2 which is relative to the protons. if V2 is equal to 2 times of v1, then relative to the test Q, electrons is moving downward with V1 relative to the test Q. Thus the distance between electrons to the test Q will be still d1. Am I correct…

[@PhysicsMadeEasy]

@@Paulfly Hello Paul, Yes you are correct, if V2=-2V1, the length contraction for both protons and electrons would be the same, thus, positive and negative charge densities in perspective of charge q+ should be the same, so no net force. But in my video there is a little imprecision… (which occurs in all lectures I have seen up to now about that, even Feynman’s !): The effect becomes significant at relativistic speeds for the charge q+. So the situation you propose would not really happen. Imagine you accelerate a proton (the test charge) in vacuum with a simple 9V battery. I calculated that the speed for a proton would be in the tens of thousands of m/s (roughly 42 km/s), and for an electron in the millions (roughly 1800 km/s). While the drift velocity of electrons in the wire electrons is tiny (a few mm per second). What actually counts is the difference of perceived velocities between positive charges and negative charges in the cable. This tiny difference at small (non-relativistic) velocities is insignificant, but has a significant effect when the speed of the test charge becomes relativistic (look at the structure of the length contraction formula). The example on the video is more of a thought experiment, reality as it is, would have been very difficult to represent accurately in an animation… I should have discussed this in the video, but I believe this would have provided more confusion than clarity… (my videos are intended to provide the viewer with a first step towards a knowledge that they can then develop by themselves…). Oh, by the way, your comment was excellent. Well done ! Be well

[@vincecox8376]

Please get tuned into facts, 1. anti gravity is a product of the center field of a magnet. 2. the center of a magnet when vibrated will repel water 3. If you vibrate granite rock with the center field of a magnet at the correct frequency it will turn like butter. that's just the beginning it will play a Hugh part of our country's future. This is only applicable to none iron type material such as glass or plastic. If you have a bar magnet simply tap the center near a trickle of water and watch the water move out of the way. Tap the center field on any none metalic surface and watch it loose weight. You can not use a sign wave type vibration it must be saw tooth . A sign wave signal contains the centerfield, that's what pushes AC and radio signals around the world. A sign wave has three elements on an oscilloscope you only see the two , On a scope you see the positive cycle and the negative cycle you never see the most significant part of the cycle and that is the center field that produces the energy to push the energy forward!!! There is allot to be learned about the magnetic center field .. Please help spred the news ..

[@siddharthpotti203]

According to special relativity, when a charge moves, or a charge is seen from a moving reference, its electric field morphs into a magnetic field. My question is then, why does the electric field still exist in a moving charge - shouldnt it just have a singular magnetic field?

[@PhysicsMadeEasy]

Hi Sid, it doesn't morph, it appears to morph, but it is the same thing just seen from another perspective! In the past, magnetism and electricity were separated conceptually. Maxwell realized he could put them together, as two sides of the same coin. Then, Einstein explained why it could be done (relativity). Your question makes me think that you are separating electric and magnetic fields like two different things... there are the same thing just seen from different perspectives. I hope my answer helps!

[@JustNow42]

Actually the magnetic field generated by a moving electric charge is the kinetic energy of the charge. Very cool.

[@PhysicsMadeEasy]

Using the verb 'to be' is a short cut I wouldn't take here: but I could rephrase your sentence: "Actually the magnetic field generated by a moving electric charge is somehow related to the kinetic energy of the charge carrier."

[@marcseghatol6583]

Great

[@sammyapsel1443]

in section 2, i think the effect at 6:51 isn't due to special relativity but because of the rolling shutter effect just fyi.

[@PhysicsMadeEasy]

The two pictures are actually the same picture, one I thinned artificially for illustrative purposes: there is no way at a speed of 5m/s, I would be able to detect the effect. for fun, following your comment, I just calculated the effect: for an object of 1 meter in length, the length contraction effect would have been about a half of a femtometer (that's smaller than the diameter of proton). :-)

[@Rajbirsingh-ef5mb]

Plz post a video on charge producing em wave with linear acceleration beacuse very very difficult to understand plz plz plz no one knows about it i have seen video which is very old and not understand properly It will helpful for all physics lover

[@PhysicsMadeEasy]

There is a thread that i pinned in one my videos that should help you with that. This is the video: kzbin.info/www/bejne/npyZZKiLndCNfpYsi=YcV9GcBwO9ssQYBQ Go directly to the comment section, in the pinned thread started by visasaarinen6051, we discuss this with some links to simulation videos.

[@TOKAYASSHOP-hl2gw]

Hi I thought length contraction happens when moving in the same direction than motion observed not opposite direction.. can you help me here? Thanks

[@PhysicsMadeEasy]

Hi, Length contraction occurs when there is a difference between the velocity of the observer and of what is observed. The direction doesn't matter (as expressed by the square on the v in the length contraction formula). If an observer, moves in the opposite direction than the observed object, the speed difference between the two increases, thus length contraction becomes even more pronounced.

[@TOKAYASSHOP-hl2gw]

@@PhysicsMadeEasy i think I’m missing something, doesn’t Lorentz say that length contraction happens in the direction of movement?

[@vincecox8376]

Please get tuned into facts, 1. anti gravity is a product of the center field of a magnet. 2. the center of a magnet when vibrated will repel water 3. If you vibrate granite rock with the center field of a magnet at the correct frequency it will turn like butter. that's just the beginning it will play a Hugh part of our country's future. This is only applicable to none iron type material such as glass or plastic. If you have a bar magnet simply tap the center near a trickle of water and watch the water move out of the way. Tap the center field on any none metalic surface and watch it loose weight. You can not use a sign wave type vibration it must be saw tooth . A sign wave signal contains the centerfield, that's what pushes AC and radio signals around the world. A sign wave has three elements on an oscilloscope you only see the two , On a scope you see the positive cycle and the negative cycle you never see the most significant part of the cycle and that is the center field that produces the energy to push the energy forward!!! There is allot to be learned about the magnetic center field .. Please help spred the news ..

[@danamarvich5125]

Awesome video!

[@PhysicsMadeEasy]

Thank you for your encouragement Dana!

[@sanjeewakap1062]

Thanks a lot

[@PhysicsMadeEasy]

You are welcome Sanjee

[@marcjones744]

So is magnetism the flow of electrons of a material from the northern pole of that material to the southern pole. It's a force from the north to the south, but a force upon, "what", exactly?

[@PhysicsMadeEasy]

Hello Marc, In your comment you ask if Magnetism is a flow of electron : It is not, it emerges around a flow of charges (in the case of a metallic wire, these charges are carried by electrons). Magnetism is not a force either... Magnetism is the subsection of physics that studies magnetic phenomena. Magnetic forces appear when you place a magnetic dipole (a magnet) in an external magnetic field (created by another magnet). The N gets pulled to the S of the magnet creating the field, and the S to the N , so it makes the magnet you placed in the field turn: The force is actually a pair of 'turning force' a torque. I have a video that discusses this in detail here: kzbin.info/www/bejne/oniUhYNrYtd-nK8

[@marcjones744]

@@PhysicsMadeEasy thanks so much... I will take a look

[@danblankenship5744]

Wow, way to twist my mind's eye. This isn't the first time when the truth changed my previous understanding. I remember when I was young taking a bath. I noticed the water drops leaking from the tap would change to a circle as it fell. I decided that this must be proof that the water drop had its own gravity. Later I heard it was due to skin-effect. Then my mind fashioned a new picture for gravity. I then postulated that the force that makes the earth shaped as a ball is skin-effect, and the atmosphere (in concentration bands) is held around this ball by the same effect. All creatures on the surface of the ground is held in place by the densest layer of the atmosphere. I will never forget these formulas developed by a 7-year old's mind and sometimes I refer back to this image to see if it stands up to scrutiny.

[@PhysicsMadeEasy]

Hello, thank you for sharing this story with us. You were a curious kid trying to understand the world. that is so commendable! Seeing the waterdrop becoming spherical, and saying that it was because it must exert some gravity on itself was pretty brilliant for such a young age :-). I do not know where you are now, but just think that there is a common point in all physical phenomena, the tendency for any object to minimize its energy state... (that's where the 'skin effect ' comes from).

[@aminnima6145]

Love it, thank you

[@PhysicsMadeEasy]

You are warmly welcome :-)

[@vincecox8376]

Please get tuned into facts, 1. anti gravity is a product of the center field of a magnet. 2. the center of a magnet when vibrated will repel water 3. If you vibrate granite rock with the center field of a magnet at the correct frequency it will turn like butter. that's just the beginning it will play a Hugh part of our country's future. This is only applicable to none iron type material such as glass or plastic. If you have a bar magnet simply tap the center near a trickle of water and watch the water move out of the way. Tap the center field on any none metalic surface and watch it loose weight. You can not use a sign wave type vibration it must be saw tooth . A sign wave signal contains the centerfield, that's what pushes AC and radio signals around the world. A sign wave has three elements on an oscilloscope you only see the two , On a scope you see the positive cycle and the negative cycle you never see the most significant part of the cycle and that is the center field that produces the energy to push the energy forward!!! There is allot to be learned about the magnetic center field .. Please help spred the news ..

[@Zilron38]

Very interesting, but what is a field? it seems to be a force applied over a distance of empty space from source A interacting with source B. I don't believe it can not be nothing therefore a field is some sort of reality we have not discovered or understood yet. Does it bend or twist space time or do these particles exists on a different superimposed plane of existence with it's own rules, and/or are there several planes of existence superimposed on each other that are unique to each sub particle type and each plane of existence has it own rules to interact with other planes? maybe we may never know.

[@PhysicsMadeEasy]

Well I know someone that has read about QFT (Quantum Field Theory), haha ! The video here is within a classical physics context, where fields are mathematical tools that model well reality as we experience it. If you dig deeper, like quantum mechanics does, then fields appear to become real, although these are not fields of force but as you say , fields for which a disturbance is perceived as an elementary particle (or more precisely by the effect of its set of properties). As you seem to be enjoying this kind of reflexion, here's some food for thought: Are we sure that it is the fields / particles that exist? or could it just be their properties? And even wilder, maybe what exists is just the interactions (that we perceive being between properties)… Have fun with that lol !

[@Zilron38]

@@PhysicsMadeEasy Thanks for the response :) I definitely do enjoy this reflexion. I always like to understand how things "operate under the hood" and most forces that we can see and touch are pretty well understood and make sense, but my brain just can't comprehend how fundamental forces operate. We know this is how it is, but not why it is. I find it truly fascinating.

[@glage]

when the positive charge is not moving, the electrons moving downward should appear denser in the charge's perspective, why doesnt the cabe attract the charge when the charge is not moving?

[@PhysicsMadeEasy]

Good question @glage. It already popped up in the comments, and I responded to it. Search for the comment by @spencerwenzel7381, he asks a very similar question. I made a detailed reponse.

[@_cul8r_]

How can this explain why 2 current carrying cables will be attracted together when current flows in the same direction but repel when current flows in the opposite direction?

[@PhysicsMadeEasy]

This video discussed the emergence of a magnetic field from an electric current in a wire within the context of the theory of special relativity. If you place another cable with current within this magnetic field, the moving charged particle within that cable will experience magnetic forces. It becomes a hectic quite quickly to interpret everything using special relativity, so that's where the hand rules become useful (a visual and intuitive application of Maxwell equations)

[@KRSNA_21]

Sir electric potential is work done on unit +ve charge so can we say electric potential is potential energy

[@PhysicsMadeEasy]

You are correct in saying that the electric potential is the potential energy that 1 unit of charge would have, but what you are missing is that this happens only when that charge is placed at a position having that electric potential. Intrinsically it is not the same thing: An electric potential is a property of a position: it tells you the PE that a charge would have when placed at that position, per unit charge (PE = q * V). Potential energy is a property of an object (How much PE it has) I have a video on this: Check it out: kzbin.info/www/bejne/oGSqo4KBp8qSlZIsi=r5I2KqnQwVTyucon

[@md.showravbinkashem3331]

Why does the test charge at rest feel no force due to length contraction as electrons are moving in perspective of this test charge?

[@PhysicsMadeEasy]

Good question... Another viewer asked the same thing, and I already answered it. Check the comment of @spencerwenzel7381 under the same video (what is a magnetic field?) to read the answer.

[@bsure4]

how does hydrostatic pressure work in a very thin 1/4 tube ? Your videos are excellent!

[@PhysicsMadeEasy]

Hi, what do you mean by 'work'...

[@SmitGajbhiye]

Thank you sir I really struggle in ray optics Will u make videos on this topic in future?

[@PhysicsMadeEasy]

Hi, unfortunately, it is not on my plate right now... You may have noticed I really am in an "electromagnetic mood" right now! Maybe when I get out of it... Refraction by a lens, which relates to ray optics, is a topic that interests me, and I might explore in the future, but that is not going to be soon. Sorry.

[@SmitGajbhiye]

@@PhysicsMadeEasy It's totally Fine professor I am waiting for next lecture. Thank you

[@BigHAL9001]

Hi, can you explain how a parallel pair of current carrying wires can have a magnetic attractive force between them? When the currents are both equal and moving in the same direction there is no relative difference in any of the motions of the charges in the two wires. Thanks.

[@PhysicsMadeEasy]

Hello, Let’s consider your example and name wires A and B. The currents in the wires are parallel and in the same direction (let’s imagine downwards). What are the electrons in wire A « seeing » while they move ? From they perspective, they see the electrons in wire B at rest. No length contraciton there. But they also see the positively charged metallic ions moving upwards… Positive charges will appear to get denser, and wire B will appear positive, so the electrons moving in wire A will be attracted by wire B. Repeat this reasoning for the electrons moving in wire B, and you’ll see that these are attracted to Wire A… Of course this is a simplified view, within each cable things are a little more complex than this, but you get the general idea… I hope this clarifies things!

[@BigHAL9001]

@@PhysicsMadeEasy Thanks yes it does, but won't where also be a repulsive force acting between the two wires due to the moving positive changes?

[@fysics_nerd0.0073]

I have a question, when we have the same speed as the cable, when we are "standing still", the protons will not move, but if there is current in the cable as in this example the electrons will move, why does that not cause the electrons to undergo length contraction, which would then lead to a proton beside the wire to be attracted?

[@glage]

i have the same question, pls tell me if u find the answer to it

[@PhysicsMadeEasy]

This question already popped up in the comments, and I responded to it. Search for the comment by @spencerwenzel7381, he asks a very similar question. I made a detailed response.

[@fysics_nerd0.0073]

@@PhysicsMadeEasy I found the comment, the explanation was good, but if the difference in velocity stays the same as you reach relativistic velocities, that does not mean that the kinetic energy difference between the electrons and protons get bigger and bigger. I mean closer to the speed of light differences in velocity will have bigger differences in kinetic energy, doesnt the law of conservation imply that the difference in velocity will decrease? Would that then mean that the electromagnetic force difference caused by length contraction is the same regardless of the speed of the charged particle moving outside the wire? (I am not refuting you I am just asking)

[@andrewjustin256]

Would you please confirm what I am saying that "magnetic field is not fundamental but is electric field's interactions that was formerly not comprehended well; thereof, it was given a new name and is essentially an electric field. Moreover we are still stuck with the of Maxwells equations, despite it describes it flawlessly, and there is no such thing as magnetic field".

[@PhysicsMadeEasy]

Hi Andrew, yes, I do confirm... But please note that this is within the context of classical physics. In quantum mechanics, Fermi proved that if the electric charge is quantized, then magnetic monopoles must exist. If such monopoles exist, that would imply that objects could have a "magnetic charge". In that case, I would need to revise my understanding regarding what magnetic fields are: Magnetic fields would be a definite "thing". But we do know that electric charge is quantized... Yet, despite many efforts we never found a magnetic monopole... Physics is really a fascinating on-going investigation.

[@andrewjustin256]

Well, thank you for clearing that but my concept is still nebulous on what you said about monopole. In addition, from Special relativity we can prove that when charge and current in a wire is flowing, the magnetic force is just electric force, but I heard from the word of mouth that from electron spin arises magnetic pole responsible for the magnetic behavior of an element and also ferromagnets, antiferromagnets and paramagnetism. It appears that magnetic field is completely different force. Would you please cast off few lines on that too?

[@PhysicsMadeEasy]

Maybe you haven't seen the 'hidden' part of the video about magnetic dipoles... At the end, after the credits, I improvised a discussion about this. An electron is spinning, and an electron is a ball of charge, thus in an electron there are loops of currents, that generate a magnetic force of the same origin than the one I discuss in the magnetic field video. Moreover, If you look at the shape of the field of an electron, you realise it is a dipole (with a N and a S), not a monopole... Check the video, it might clarify a few things kzbin.info/www/bejne/oniUhYNrYtd-nK8si=Q6tE3dTffDBKKmVS ...

[@muntee33]

Woah woah woah, let's walk it back a bit first and establish our understanding from a base line principle. First we must qualitatively explain and demonstrate the elementary component of your preposition. (Which we have not even yet done in any/all of physics yet, so good luck. Haha) And that elementary component is... What IS a field?

[@PhysicsMadeEasy]

Well Muntee, maybe you should explore my channel a little more in depth... and you'll find this haha! There is even a video called 'what is a field?', another called 'what is an electric field' and others that details more physics basics... Note that I agree 100% with your pedagogical approach: make sure that a student has a good grasp of the fundamentals first...

[@turkishwithemre]

The thing ı don't understand why magnetic field turns around the cable and what is its effect ?

[@PhysicsMadeEasy]

As discussed in the video, the shape of the magnetic field lines around a cable with current is justified by the behavior that a moving charge located close to that cable has (to explain such behavior, the field line need to be perpendicular to the direction of the current, and to make sure of that, perpendicular to the radius of the circle around that current).

[@sbjchef]

what is a magnetic field emerging into or what am I pushing against with two permanent magnet north poles facing each other?

[@PhysicsMadeEasy]

Each magnet (= a magnetic dipole) creates their own magnetic field of which the other magnet will feel the influence. If you place the two magnets directly face to face (North to North), They will want to turn to align (one wants to rotate so that its South pole faces the North pole of the other magnet). This is what you are fighting against when you are forcing them in a North-North configuration. If you are interested in magnetism as a subject, check my video about magnetic dipoles, it should help understand what I said above.: kzbin.info/www/bejne/oniUhYNrYtd-nK8

[@sbjchef]

@@PhysicsMadeEasyThank you for replying, what my lay brain is trying to understand is what medium is the magnetic field line propagated through and what medium is being altered by the magnetic field to create the path of the field. Is magnetism transmitted via quanta such as photons are to light or is it something warping spacetime in the same way energy density creates gravitational effects?

[@PhysicsMadeEasy]

@@sbjchef That's what Einstein tried to do all the rest of his life: could the electromagnetic field be formalized like space-time with a curvature? The maths just didn't work (infinities showing up I think)... As for your first question, the medium is empty space (like for electric fields)

[@hopcfizl3671]

Is there an explanation for why current is opposite of moving charge or is it just and agreement? And won't there still be electrical force on the charge from the current going through wire even when it's not moving? I don't see how the wire with current could be neutral.

[@PhysicsMadeEasy]

Hi, Yes, it is an 'agreement', as suggested by the name 'conventional' current. If you take a piece of metal (like a piece of wire), the number of electrons is the same as the number of protons, thus the charge density is zero. That doesn't change for the observer at rest if the electrons are moving uniformly in the wire. Finally, because the cable is electrically neutral, it will not generate a net electric field at the level of an external test charge at rest, so there will be no electric force on the latter.

[@vincecox8376]

Please get tuned into facts, 1. anti gravity is a product of the center field of a magnet. 2. the center of a magnet when vibrated will repel water 3. If you vibrate granite rock with the center field of a magnet at the correct frequency it will turn like butter. that's just the beginning it will play a Hugh part of our country's future. This is only applicable to none iron type material such as glass or plastic. If you have a bar magnet simply tap the center near a trickle of water and watch the water move out of the way. Tap the center field on any none metalic surface and watch it loose weight. You can not use a sign wave type vibration it must be saw tooth . A sign wave signal contains the centerfield, that's what pushes AC and radio signals around the world. A sign wave has three elements on an oscilloscope you only see the two , On a scope you see the positive cycle and the negative cycle you never see the most significant part of the cycle and that is the center field that produces the energy to push the energy forward!!! There is allot to be learned about the magnetic center field .. Please help spred the news ..

[@The_Green_Man_OAP]

There's a problem with what you are saying. Here is my explanation: CHARGES IN A WIRE ACTUALLY _DRIFT SLOWLY_ , BUT (MASSLESS) WAVES IN WIRES _TRANSMIT FAST._ Therefore, the relative motion is between _parts of traveling waves_ and fixed observer(s), _NOT between moving masses._ So, to clarify: The _relative motion_ in the wire is to do with the _transmission of energy_ (aka _force or impulse:_ two way action/reaction), _NOT_ (one way) _mass transfer._

[@zBrush01]

😮

[@PhysicsMadeEasy]

What do you call massless waves (the official term)?

[@vincecox8376]

Please get tuned into facts, 1. anti gravity is a product of the center field of a magnet. 2. the center of a magnet when vibrated will repel water 3. If you vibrate granite rock with the center field of a magnet at the correct frequency it will turn like butter. that's just the beginning it will play a Hugh part of our country's future. This is only applicable to none iron type material such as glass or plastic. If you have a bar magnet simply tap the center near a trickle of water and watch the water move out of the way. Tap the center field on any none metalic surface and watch it loose weight. You can not use a sign wave type vibration it must be saw tooth . A sign wave signal contains the centerfield, that's what pushes AC and radio signals around the world. A sign wave has three elements on an oscilloscope you only see the two , On a scope you see the positive cycle and the negative cycle you never see the most significant part of the cycle and that is the center field that produces the energy to push the energy forward!!! There is allot to be learned about the magnetic center field .. Please help spred the news ..

[@EduardOganesian]

OK, what about a charge moving perpendicularly to a current wire? The charge will experience a force sideways, can this be predicted by Special Relativity as well?

[@marciliopc]

to use Lorentz contraction the charge velocity must be in the order of the light velocity. The electron velocity in a cable is too small (cm per second). So how do you justify this use?

[@PhysicsMadeEasy]

Yes but a charge moving next to the cable will have a velocity being a significant fraction of c. At these velocities of the moving charge, the differential between positive and negative charges velocities in the cable, which is small in absolute, should become significant in the perspective of that moving charge.

[@mahirbalayev5835]

If magnetic field doesn't exist indeed, then what is magnetic field of electromagnetic wave indeed, could you please explain?

[@mahirbalayev5835]

And if magnetic field occurs due to length contraction, then why is there magnetic field in wave? Could we assume that it occurs due to extending/curving of spacetime?

[@PhysicsMadeEasy]

Hello Mahir, to find a coherent answer to your question, you need to think about the source of the oscillating electric field in an EM wave... It will be an oscillating charge (i.e a charge in motion). it generates an oscillating electric field, and because the charge is moving, a magnetic field emerges too, that will propagate along the oscillating electric field).

[@PhysicsMadeEasy]

Answer to your first question in my other answer. Regarding the curvature of space time, within the framework of our discussion, not really... Otherwise we would have a theory unifying gravity and electromagnetism. Space time might be curved a little bit though as it will be affected by the energy carried by the wave, but the effect would be negligible.

[@mahirbalayev5835]

@@PhysicsMadeEasy does it mean that fields (electric or magnetic) from point source just pull each other because of direction of each field?

[@vincecox8376]

Please get tuned into facts, 1. anti gravity is a product of the center field of a magnet. 2. the center of a magnet when vibrated will repel water 3. If you vibrate granite rock with the center field of a magnet at the correct frequency it will turn like butter. that's just the beginning it will play a Hugh part of our country's future. This is only applicable to none iron type material such as glass or plastic. If you have a bar magnet simply tap the center near a trickle of water and watch the water move out of the way. Tap the center field on any none metalic surface and watch it loose weight. You can not use a sign wave type vibration it must be saw tooth . A sign wave signal contains the centerfield, that's what pushes AC and radio signals around the world. A sign wave has three elements on an oscilloscope you only see the two , On a scope you see the positive cycle and the negative cycle you never see the most significant part of the cycle and that is the center field that produces the energy to push the energy forward!!! There is allot to be learned about the magnetic center field .. Please help spred the news ..

[@manudehanoi]

arent magnetism and electric force interchangeable in relativity, such that yes you can say magnetism is a relativistic effect of the electric force but you could say just as well that the electric force is a relativistic effect of the magnetism ?

[@PhysicsMadeEasy]

Well done Manu, I had the same thought when scripting the video. My answer to that is that electric monopoles exist (common electric charges), but not magnetic monopoles. That means that a single system, whatever its size, cannot have a magnetic charge. This is also implied in Maxwell's 2nd equation. In other words, we are not in a chicken and the egg situation: Magnetic fields cannot be the starting point, electric fields are. Of course, there is always the idea that according to Dirac, magnetic monopoles must exist in the universe, (even if there would be only one) .These must be extremely rare because despite much efforts, none have been detected yet. I really like this topic, I might make a video on this. I love the fact that when I research for a video, it triggers questions in me, and thus, gives me ideas for new videos!

[@manudehanoi]

@@PhysicsMadeEasy im not sure I get your point about single systems not aving a magnetic "charge". I could say that a dipole is a single system. I think it's just a matter of instinct, the electric field is just a simpler phenomenon than the mag one, therefore we are tempted to put it higher in the causal chain

[@PhysicsMadeEasy]

@@manudehanoi The instinct you mention is a good one, a version of Occam's razor. As discussed magnetic system only come as symmetric dipoles... thus the "magnetic charge" of such system is always zero... that means that there can be any net magnetic flux across a closed surface (2nd Maxwell law). In the absence of any system that can have a non zero magnetic charge, while net electric charges are common, one would indeed tend to put electric field higher on the causal chain (very good expression btw). I am actually reflecting on this, and may produce a video on these reflections. At the current state of my thoughts, I am starting to consider that what really can be considered as 'existing' is the electromagnetic field, made of two indissociably linked components: electric and magnetic fields... What do you think?

[@manudehanoi]

@@PhysicsMadeEasy I think last i tried to make magnetic calculations it was a fantastic pain in the ass, getting an understanding of the mag field also is, the mag flux is ...Anyways, without being able to prove it, id put it as a consequence of the electrical field.... However I think maxwell put the mag and electric field as coexisting and without any delay between one and the other, plus each time I ask if the light wave propagates because the change in electric field causes a change in mag field and that causes a change in the elec field and so on, I get a different answer....So I gave up

[@zakirhussain-js9ku]

What is magnetic field made of.

[@PhysicsMadeEasy]

Hi Zakir... check the video :-)

[@williamwalker39]

This effect has nothing to do with Relativistic length contraction. If a positive charge moves parallel to the wire at the same speed as the electrons flowing due to current in the wire, then the current creates a magnetic field that generates a force on the moving positive charge, causing it to move away from the wire according to the Lorentz force law. From the perspective of the moving positive charge, it thinks it is standing still, and that the wire generating a magnetic field is moving. According to Maxwells equation's, a moving magnetic field creates an electric field that creates a force on the charge causing it to move away from the wire. Relativistic length contraction and time dilation are optical illusions and are not real. This is proved in the following way. The speed of light is not a constant as once thought, and this has now been proved by Electrodynamic theory and by Experiments done by many independent researchers. The results clearly show that light propagates instantaneously when it is created by a source, and reduces to approximately the speed of light in the farfield, about one wavelength from the source, and never becomes equal to exactly c. This corresponds to the phase speed, group speed, and information speed. Any theory assuming the speed of light is a constant, such as Special Relativity and General Relativity are wrong, and it has implications to Quantum theories as well. So this fact about the speed of light affects all of Modern Physics. Often it is stated that Relativity has been verified by so many experiments, how can it be wrong. Well no experiment can prove a theory, and can only provide evidence that a theory is correct. But one experiment can absolutely disprove a theory, and the new speed of light experiments proving the speed of light is not a constant is such a proof. So what does it mean? Well a derivation of Relativity using instantaneous nearfield light yields Galilean Relativity. This can easily seen by inserting c=infinity into the Lorentz Transform, yielding the GalileanTransform, where time is the same in all inertial frames. So a moving object observed with instantaneous nearfield light will yield no Relativistic effects, whereas by changing the frequency of the light such that farfield light is used will observe Relativistic effects. But since time and space are real and independent of the frequency of light used to measure its effects, then one must conclude the effects of Relativity are just an optical illusion. Since General Relativity is based on Special Relativity, then it has the same problem. A better theory of Gravity is Gravitoelectromagnetism which assumes gravity can be mathematically described by 4 Maxwell equations, similar to to those of electromagnetic theory. It is well known that General Relativity reduces to Gravitoelectromagnetism for weak fields, which is all that we observe. Using this theory, analysis of an oscillating mass yields a wave equation set equal to a source term. Analysis of this equation shows that the phase speed, group speed, and information speed are instantaneous in the nearfield and reduce to the speed of light in the farfield. This theory then accounts for all the observed gravitational effects including instantaneous nearfield and the speed of light farfield. The main difference is that this theory is a field theory, and not a geometrical theory like General Relativity. Because it is a field theory, Gravity can be then be quantized as the Graviton. Lastly it should be mentioned that this research shows that the Pilot Wave interpretation of Quantum Mechanics can no longer be criticized for requiring instantaneous interaction of the pilot wave, thereby violating Relativity. It should also be noted that nearfield electromagnetic fields can be explained by quantum mechanics using the Pilot Wave interpretation of quantum mechanics and the Heisenberg uncertainty principle (HUP), where Δx and Δp are interpreted as averages, and not the uncertainty in the values as in other interpretations of quantum mechanics. So in HUP: Δx Δp = h, where Δp=mΔv, and m is an effective mass due to momentum, thus HUP becomes: Δx Δv = h/m. In the nearfield where the field is created, Δx=0, therefore Δv=infinity. In the farfield, HUP: Δx Δp = h, where p = h/λ. HUP then becomes: Δx h/λ = h, or Δx=λ. Also in the farfield HUP becomes: λmΔv=h, thus Δv=h/(mλ). Since p=h/λ, then Δv=p/m. Also since p=mc, then Δv=c. So in summary, in the nearfield Δv=infinity, and in the farfield Δv=c, where Δv is the average velocity of the photon according to Pilot Wave theory. Consequently the Pilot wave interpretation should become the preferred interpretation of Quantum Mechanics. It should also be noted that this argument can be applied to all fields, including the graviton. Hence all fields should exhibit instantaneous nearfield and speed c farfield behavior, and this can explain the non-local effects observed in quantum entangled particles. *KZbin presentation of above arguments: kzbin.info/www/bejne/qZazlX1tq7iErLM *More extensive paper for the above arguments: William D. Walker and Dag Stranneby, A New Interpretation of Relativity, 2023: vixra.org/abs/2309.0145 *Electromagnetic pulse experiment paper: www.techrxiv.org/doi/full/10.36227/techrxiv.170862178.82175798/v1 Dr. William Walker - PhD in physics from ETH Zurich, 1997

[@robinhooper7702]

Good day. I love physics but I have a question that I just can't find answer to, or perhaps I'm not asking it incorrectly. How is it that I may be able to contact you to ask and clarify my inquiry? Thanks. Oh, and it is not a school lesson question.

[@PhysicsMadeEasy]

Hello Robin, why don't you ask it here? (Don't reply to that comment, generate a new comment, or I might miss it )

[@vincecox8376]

Please get tuned into facts, 1. anti gravity is a product of the center field of a magnet. 2. the center of a magnet when vibrated will repel water 3. If you vibrate granite rock with the center field of a magnet at the correct frequency it will turn like butter. that's just the beginning it will play a Hugh part of our country's future. This is only applicable to none iron type material such as glass or plastic. If you have a bar magnet simply tap the center near a trickle of water and watch the water move out of the way. Tap the center field on any none metalic surface and watch it loose weight. You can not use a sign wave type vibration it must be saw tooth . A sign wave signal contains the centerfield, that's what pushes AC and radio signals around the world. A sign wave has three elements on an oscilloscope you only see the two , On a scope you see the positive cycle and the negative cycle you never see the most significant part of the cycle and that is the center field that produces the energy to push the energy forward!!! There is allot to be learned about the magnetic center field .. Please help spred the news ..

[@fakechecknumber1198]

ART BELL/MADE AN ANTENNA THAT COLLECTED ENERGY ❤

[@kimbowaaloysius1181]

We, therefore, live in an electric universe

[@PhysicsMadeEasy]

A little too general, don't forget gravity, strong and weak forces! But it's true that at human scale, only electric and gravitational forces appear to have an effect. Even mechanical forces are electric in nature!

[@Asaad-Hamad]

Lengthy contraction formula is Lotentz's formula not Einstein

[@PhysicsMadeEasy]

You are fully correct, Einstein was looking for a mathematical model that would satisfy the 2 postulates of relativity. Well he found one when he looked at Lorentz transformations, which were developed by Lorentz within the frame of Ether Theory. Lorentz was trying to explain why the motion of the Earth through the Ether could not be detected by Michelson at the end of the 19nth century, thus attempting to save Ether theory. He failed, but the maths developed by Lorentz were sound and were perfect for Einstein's needs! Thank you Asaad for setting things straight!

[@Asaad-Hamad]

Fitzgerald was the first one to theorize for this idea and explained the result of Michelson experiment, but it was Lorentz who made the formula for this explanation, that was during the golden era of cracking down the code of the universe, as much pleasure as someone get from knowing more about how the universe works, sometimes people like you come over and make it even more by mastering the art of explaining.

[@Naomi_Boyd]

This makes no sense. If the observer is moving relative to the cable, it is the length of the cable, as a whole, which would seem to contract. All of the charges within the cable would contract with it. It is the electrons and not the space between them moving. The observer on the train and the observer on the platform might not agree on the length of a section of track, but they must agree on the number of rotations the wheels make when crossing that section of the track. If the number of electrons and protons are the same in each section of wire, that must hold true in all frames.

[@PhysicsMadeEasy]

Hello Naomi, I didn’t say that the number of charges in the cable changed depending on the frame of reference, just that their density was perceived larger… Maybe you referring to the illustrations where you do not see the length of the cable contract because it is longer than the screen and homogeneous. Yet, in essence, you are correct, 1 meter of cable will appear to shrink for a moving frame of reference, and thus the density of charges within it. On the other hand, I am not sure your analogy with the train wheels is pertinent. Imagine Bob on the train at a velocity close to the speed of light, and Alice motionless on the station’s platform. For both, the number of rotations for the train wheels to go from A to B is the same. We agree: It is the circumference of the wheels that change (distance covered per rotation) because the horizontal axis of the wheel would appear smaller in Alice’s perspective (the wheels would appear elliptical). The factor by which the wheel horizontal axis is smaller for Alice compared to Bob will naturally be the same than the contraction perceived for the distance AB. Another way to say that the number of rotations will be the same for both observers.

[@web_physics]

Moving charge produce magnetic field 😮magnetic force per unit moving charge is magnetic field 🏑🧲

[@PhysicsMadeEasy]

Yes, I guess you could define a magnetic field as the force experienced by a moving positive charge per unit charge and per unit of velocity of that charge, and that for a given relative orientation of the velocity vs that of the magnetic field strength vector.

[@vincecox8376]

Please get tuned into facts, 1. anti gravity is a product of the center field of a magnet. 2. the center of a magnet when vibrated will repel water 3. If you vibrate granite rock with the center field of a magnet at the correct frequency it will turn like butter. that's just the beginning it will play a Hugh part of our country's future. This is only applicable to none iron type material such as glass or plastic. If you have a bar magnet simply tap the center near a trickle of water and watch the water move out of the way. Tap the center field on any none metalic surface and watch it loose weight. You can not use a sign wave type vibration it must be saw tooth . A sign wave signal contains the centerfield, that's what pushes AC and radio signals around the world. A sign wave has three elements on an oscilloscope you only see the two , On a scope you see the positive cycle and the negative cycle you never see the most significant part of the cycle and that is the center field that produces the energy to push the energy forward!!! There is allot to be learned about the magnetic center field .. Please help spred the news ..

[@MadocheMercuis]

​@@PhysicsMadeEasyq I

[@digbysirchickentf2315]

Did you mention who came up with this hypothesis?

[@PhysicsMadeEasy]

Einstein... :-) And it was not really an hypothesis, but more of a result from the theory of special relativity (the latter being based on two postulates that are verified experimentally).

[@digbysirchickentf2315]

@@PhysicsMadeEasy Electrons in a wire move around 4mm per second, hardly relativistic speeds?

[@PhysicsMadeEasy]

@@digbysirchickentf2315 detailed answer here: physics.stackexchange.com/questions/210286/how-can-relativistic-effects-be-the-cause-of-magnetic-forces-when-the-normal-spe

[@digbysirchickentf2315]

@@PhysicsMadeEasy Detailed quackery, this is all BS. Shame on you, show some critical thinking.

[@PhysicsMadeEasy]

@@digbysirchickentf2315 What? Have you looked at the link I told you? (the answer by Emilio Pisanty). The relativistic effect is extremely tiny, and it disturbs in an extremely tiny way a balance between huge amounts of charges (the positive and negative charges within the same a cable...). So the effect becomes measureable. Please be more moderate in your choice of words when you do not agree.

[@fishrockets]

If a positive particle is pushed away by the wire when it moves, should it not be pulled into the wire at rest? If the positive particle is at rest, and the electron flows, than wouldn't the electrons contract, so to speak, making the density of electrons greater in a given area?

[@PhysicsMadeEasy]

Very relevant question @fishrockets. @spencerwenzel7381 asked a similar question. I answered it . Please check it out in the comments.

[@lw5359]

You only just barely touched on it, but I think your explanation of the magnetic field generation in a permanent magnet was quite incomplete, and most likely not correct. Heaviside said the field of a permanent magnet was a point-source phenomenon, not a summation of a bunch of tiny molecular "movements".

[@PhysicsMadeEasy]

A magnetic field can never be a punctual source. The source of a magnetic field must be a dipole... Some of Fermi's calculations show that magnetic monopoles should exist, but never has one been observed despite a lot of experimental efforts... Some believe that if such monopoles do exist, these are so rare that there might not even be one in the observable universe.... Check my video on magnetic dipolar moment, it should interest you. kzbin.info/www/bejne/oniUhYNrYtd-nK8

[@vinniepeterss]

cool😢

[@cristig243]

No human knows what a magnetic field is .

[@guitarizard]

I do.

[@aiden_aiden]

what do you mean by that?

[@kennyfordham6208]

Indeed, he explains equations and the movement of electric forces, but there's no specific definition of what that 'force' is. The 'force' can be detected, and it can do what we want it to do, but exactly what it is, remains a mystery.

[@guitarizard]

Veritasium, what is a force.

[@tedzone5544]

​@@guitarizardthanks

[@chadkline4268]

No, this isn't correct. And taus certainly are fundamental, as fundamental as muons and electrons. It's complex and well understood how muons transition into taus and vice versa. Not sure if i want to make the effort to explain.

[@PhysicsMadeEasy]

@@chadkline4268 are you sure you are commenting under the right video/channel? Where did I say that a tau is not an elementary particle ??? Of course it is!

[@chadkline4268]

​​​​​​​​​@@PhysicsMadeEasyok, listening again 😊 ok, you said a magnetic field is just an electric field from the view of a (relativistic) moving frame of reference 10:03 and you say 1 minute later that magnetic fields are just an emergent phenomena, and not fundamental. And I say taus are the magnetic field particles, not anything else. And muons are the electrical field particles. And that the 3 leptons and their anti particles certainly are fundamental and not simply emergent due to frames of reference. I am trying to consider what to say now because the explanation requires physics that I cannot type here. This is not a correct explanation of the origin of magnetic fields, and there is not only one cause/situation that manifest magnetic fields, and I don't think this is a good forum to discuss it because there is just too much ground to establish to understand these things in a comprehensive manner. This is a vast topic that includes the relationships between leptons, particle production, decay, photons, neutrinos, and specific energies. I forgot what the question was and need to view the video again. I really just wanted to make these little points. That it's not so simple as the video says.

[@chadkline4268]

​​​​​@@PhysicsMadeEasyafter reviewing the video again, I'd say that a lot of assumptions are being made, such as the nature of metallic bonds being electrostatic due to currents (I know that's the theory, but i don't think it's that simple, I haven't seen any calculations that explain that; I call that pretending to know what we don't truly understand) and that the relationships between lepton production and decay (and photons and electromagnetic energies and neutrinos) is not easily described, and varies with particular situations/conditions. This is very deep and complex stuff where the physics community doesn't know as much as they claim to know. We're only beginning to understand these things, and those that truly grasp it are few and not well recognized.

[@chadkline4268]

​​​​​@@PhysicsMadeEasyI'll just say this, something everyone can understand: a photon, a particle of light, is a discrete electric+magnetic field bound together. The “mass” of a photon is the momentum contained in its electric and magnetic fields, so .. I leave that for a reader to stick in their pipe and smoke 😆 no metal cable there. No electrons there. And there are no magnetic monopoles, but electrical charges do exist independently of each other; eg, free electrons. Fundamental particles (electron, muon, tau, the 6 quarks, and their anti particles) exist as mass confined to 2 dimensions, which when positively curved through the 3rd dimension, result in a contraction of spacetime, which is the origin of gravitational field. The only forces in the universe are the electromagnetic force, and those due to distortions of space. Matter possesses charge. Energy is stored in the electric and magnetic fields of matter as a consequence of its charge and the motion of its charge. I agree to that. Current is a mass with kinetic energy and field energy components, but a photon comprises only energy. I say mass-energy must always be preserved, and is not altered by perception due to relativistic frames of reference. That mass-energy is real and tangible and independent of someone's perspective.

[@starexplorers1202]

The magnetic field is a CIRCULAR feedback loop. It can NOT be defined simply by saying it is a force manifesting from a moving frame of reference or that it somehow relates to electrons moving around the atom (another wrong concept) on the atomic level. The magnetic field has all of the geometric properties of a standing wave (2-directional) with it's magnetic field vectors being antiparallel. It is this WRONG view of magnetism that has persisted since special relativity was developed in 1905 that prevents physicists from solving the Theory of Everything. While not discussed in this video, it is also wrong to view magnetism as a circular dimension. String theory has the principle of superposition built right into its concept yet theoretical physicists have completely ignored this principle as being physically real. Why is that? Why are we ignoring the truth and embracing circular dimensions and making our theories untestable? Are theoretical physicists just afraid to solve the Theory of Everything?

[@PhysicsMadeEasy]

I embrace alternative views as they allow to take perspective, and sometimes lead to significant advancements. Sometimes.... In my view, only when many serious scientist from various cultures start to consider an alternative interpretation of reality seriously, I will dig deeper and forge my opinion (a stunning example was Copenhague vs Everett's views when it come to interpreting the collapse of wave function...). For now, I am not convinced ;-) But keep exploring!

[@starexplorers1202]

@@PhysicsMadeEasy Since I am creating a series of videos based on how theoretical physicists need to at least reconsider a different view of magnetism (called The Collapse of Physics) could you tell me how I could better explain this alternative point of view. I am aware of the different articles that discuss that there is a problem over the last 100 years like "On Electromagnetic Induction" by Parry Mason and Domina Eberle Spencer in 1955 in the Journal of the Franklin Institute, Vol. 260. pp.213-226. In February of 1975 Jovan Djuric wrote his article "Spinning Magnetic Fields" in The Journal of Applied Physics. In August of 1995 Pellegrini and Swift wrote "Maxwell's Equations in a Rotating Medium: Is There a Problem?" in The American Journal of Physics. Thank you for taking the time to respond to my comment.