Magnetic field created by a current carrying wire | Physics

Magnetic field created by a current carrying wire | Physics | Khan Academy

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16 жыл бұрын

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See how a wire carrying a current creates a magnetic field. Created by Sal Khan.
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Пікірлер: 197

@leothelion634 12 жыл бұрын

this guy should start a new series: How to draw hands

@eggyrepublic 5 жыл бұрын

I can't get a hand that good by drawing on paper, and this dude just straight up draws it with a mouse.

@nokigaming6651 4 жыл бұрын

Low dpi

@photonicsauce7729 4 жыл бұрын

@@nokigaming6651 Probably a stylus maybe ?

@drprocrastinate4719 4 жыл бұрын

It’s a graphic tablet

@aryanverma7746 2 жыл бұрын

Pen tablet

@MrDavidBradfield 12 жыл бұрын

I love how you WANT to make us understand, it feels like my teachers just want to get their job done, as if its tedious

@showshowtomakefreeenergyge2426 Жыл бұрын

Quantum mechanics has attempted to explained the phenomena of magnetism by excluding Ether from the scientific community. However, many scientists have argued that this exclusion is not justified because quantum mechanics cannot account for the basic principles of electromagnetism. For example, quantum mechanics cannot explain how a current carrying wire creates a magnetic field.

@animeshverma6419 6 жыл бұрын

Who else mugging these up at 1.25x speed (it still sounds just fine ) a few hours before exam?😂🔫

@RazorFistMusicOuttaTheWorld 5 жыл бұрын

@bmzaron713 5 жыл бұрын

Epic, thanks for the tip

@PsykoShox 5 жыл бұрын

Just now xD

@rose-ni1tp 5 жыл бұрын

1.5x speed :D

@alvaropalacios8291 4 жыл бұрын

@seanbullis3364 11 жыл бұрын

"For your highschool physics class..." but what about my college physics with vector calc class lol

@silenttreatment4459 5 жыл бұрын

3:05 Soooo cute!!!!

@KonesThe 9 жыл бұрын

Not a native english. Thought I would not keep up with the video, but you actually explain very clear and understanding. Thanks.

@heatherbloom5426 6 жыл бұрын

KonesThe yeah exactly...if u watch the videos of crashcourse physics u feel a lot of difficulty in understanding but literally hank greens accent is so vivid

@student9977 3 жыл бұрын

@@heatherbloom5426 this isnt Hank greens tho

@kobuskotze7839 7 жыл бұрын

If the magnetic field direction sketches explained at 1:50 still doesn't make sense, try to imagine a moving dart. If the pointy end is moving towards you, you only see a dot. If it's moving away, you see the cross from its fins. This obviously applies to current or anything else directed"into" or "out of" the board.

@diptoneelde836 5 жыл бұрын

Wow,a ton of thanks to you.

@omarsmith6561 4 жыл бұрын

can you elaborate please as in how can you determine the direction of it

@showshowtomakefreeenergyge2426 Жыл бұрын

Quantum mechanics, the theory of the very small, has never been able to explain the phenomena of magnetism. Magnetism is created when a current carrying wire creates a magnetic field. But quantum mechanics doesn't allow for fields that are not controllable by particles. So how do we explain the magnetic field created by wires? The answer lies in the Ether. The Ether is a medium that permeates space and is thought to be responsible for creating and holding together Magnetic Fields.

@Altair4611 Жыл бұрын

You would see the fins regardless of which way it is going

@weebmaster9591 8 ай бұрын

@@showshowtomakefreeenergyge2426photons are the carriers of the electromagnetic force and the clear answer to your problem. The ether is not required and can be considered synonymous with space

@prathambabaria5834 3 жыл бұрын

Such a genuine, honest, and talented individual. I wish everyone in the world was like him.

@RazorFistMusicOuttaTheWorld 5 жыл бұрын

I love Vector Calculus Finding the total fluid force on the hemispherical tank amounted to computing a new kind of integral over a surface, or surface integral. As our course develops, we'll see a great need for integrating both functions and vector fields over nice surfaces like the hemispherical tank. Because of the complexity and importance of surface integrals, we'll have a whole chapter devoted to them. That same chapter also builds from scratch the Divergence Theorem, one of the most important results of our course. In the next unit, we'll use what we learned apprenticing for Mr. Adams at Tanks For All The Fish to begin to understand the depth of this remarkable theorem.

@Max11551 16 жыл бұрын

Cool. Had this in physics class a couple months ago, now it makes even more sense.

@larad9649 11 жыл бұрын

I have my exam tomorrow and my teacher explained this is the most un-understandable ways! you saved my life! thank you!

@MrSadik11111 10 жыл бұрын

Thank you for the method!

@LISA.WANG. 3 жыл бұрын

Wow I was getting hyped for all the comment praises for a hand he’s gonna draw, and I was not disappointed 😂👏

@LISA.WANG. 3 жыл бұрын

@@felixwang2539 😆👍

@shikhahaldar5098 3 жыл бұрын

Sir, let me take moment for truly appreciating your digital hand art so perfect 🙆🥴

@harshpatil2046 8 жыл бұрын

English is not my first language, I find it difficult to talk with people or understand what they say, but you explained it beautifully, and my doubts are cleared now, thank you Khan Academy :-)

@nirlepkaur3052 6 жыл бұрын

Thank you so much ! U solved my problem in not more than 3 minutes 😇

@FarFromEquilibrium 16 жыл бұрын

Sal I cant wait for your 5 part video on integrating Maxwells wave equation!

@dtorti4 13 жыл бұрын

dude i have to say, i loved it, i actually knew this stuff but you make it so easy to learn, appreciate the video a lot.

@kin4seikatsu844 7 жыл бұрын

Great teacher and a greater artist! Had such a hard time understanding this in lecture but you made me understand it within less then 10min. Thank you!

@sammysmith1848 6 жыл бұрын

This concept has been in use for many many years. Scrap yards use this exact same set up.

@Dan-bg5fm 7 жыл бұрын

you should quit youtube and be a professional artist . that hand you drew was on point lol

@galibkhan2260 7 жыл бұрын

he can quit utube & do a tons of things :p

@ani-bv5mq 5 жыл бұрын

Dan 😁😁

@djtoddles8750 5 жыл бұрын

Sal Khan is the Picasso of hand drawing

@crystal_royal3405 5 жыл бұрын

Lmao

@PrideofPitchers 4 жыл бұрын

He was actually a cartoon artist for his town growing up. he says it in another video lol.

@gdogvibes1 9 жыл бұрын

How is he so smart?

@jakeroflmaolol 6 жыл бұрын

pffft he a dummy

@roshanedurrani 4 жыл бұрын

He's a teacher bro

@MarkQub Жыл бұрын

14 years and video is still gold!

@jhonma1 15 жыл бұрын

Spectacular explanation than you.

@urdouchbag 13 жыл бұрын

a little explanation to the formula B=u0 i /2 (pi) r.... using gauss' theorem's equivalent in magnetics..(Ampere's Circuital Law)... B.dl=u0.i in gauss law we had..E.dS=Q/e0 so in this case.. B.(2(pi)r)=u0.i dl=2(pi)r for a circle(circumference) we have to find B... B=u0.i /2(pi)r

@NarutoMessi1 11 жыл бұрын

"That's why you don't have metal objects being thrown around by the wires behind your television set" Hilarious! :D

@sra_an9412 4 жыл бұрын

thanks it helped me

@andrewz641 5 жыл бұрын

omg the drawing is so nice

@TheOneToxic 13 жыл бұрын

can i just say you are really good at art considering your using a tablet which are hard to use XD Lovely lessons! Oh, im going to make the hand blue....very professional ;) Thanks!

@viktoriyat6131 7 жыл бұрын

In headphones, how does the current flow affect the magnetic poles in the voice coil?

@michaelburket9024 6 жыл бұрын

Is r measured from the edge of the wire or the center. I'm assuming center. My applications involves using several laminations of copper

@squarkman 15 жыл бұрын

Does the intensity of the mag field associated with electron x, move along the wire with electron x? So it would be like a spherical field force moving a foot with every foot of distance moved by electron x? But if electron x causes a mag field, this field is not affecting the electron field in the previous second so it seems like it creates a huge undefinable mess of electron fields that cannot be rigorously defined.

@user-in7jy9ed5q Жыл бұрын

wow the drawing skill lol, great video

@oversoul9248 7 жыл бұрын

how to demonstrate the expression you wrote of B created by a wire please?

@voltairer.2919 Жыл бұрын

Your English is excellent. I would never know that you are not a native English speaker.

@squarkman 15 жыл бұрын

Does the shape of this magnetic field that disipates based on the radius from the moving electron, form a sphere by adding up growing and shrinking concentric circles?

@MuneerAhmed-fx7vn 4 жыл бұрын

V nice 👍

@struggler98 11 жыл бұрын

salman thank you شكرا سلمان

@Nerdyhornist 7 жыл бұрын

how do you know everything

@chunkymonkey2285 4 жыл бұрын

bruh honestly

@shaheer_ghazi 4 жыл бұрын

God bless you

@housegfortuna1239 5 жыл бұрын

is the mu relative permeability or magnetic permeability?

@sakolsavannka5171 3 жыл бұрын

we should think about protons and neutrons if they have a moving what it makes the current the reason they make the current because of motion of protons and neutrons .

@skinner9399 4 жыл бұрын

I think the wires would repel each other.

@user-uc1fz7zl7x 2 жыл бұрын

Good

@hippoaction8310 5 жыл бұрын

how come iron filings arent affected by the magnetic field of the wire when i try it out ?

@fleshcookie 10 жыл бұрын

God Sal is a great drawer

@jpjpjpjpx 11 жыл бұрын

Seal is an artist

@shakazulutu 3 жыл бұрын

Направете превод и на български, вярно е, че много от нас знаем английски в достатъчна ст-н, но един вариант на същото това видео и с български превод, би бил много-, много по-разумен! И ще постъпите доста по-конструктивно, когато създавате едно такова видео, като го "снабдите" и с български превод ПО НЯКАКЪВ начин, хора!

@faishalreza8814 7 жыл бұрын

khan is great

@videoface12 9 жыл бұрын

So helpful, man. Thank you. This also works to describe how coherent self-awareness would go about looking at itself and how energy is in flux because it can't be created or destroyed. The universe being one of those concentric circles. Energy/magnetism = vector self-awareness

@nitishchauhan8655 8 жыл бұрын

+Alex James do you smoke crack?

@SomeGuy-pv4lr 8 жыл бұрын

+Nitish Chauhan thanks for bringing my attention back to this video. This guy is amazing. The mechanism that's happening is not one of self-awareness. It's one of experiencing the procedure of expatiation. That's the side-effect of the fusion of the electric current and plasma. Space is spinning counter clock wise while time is spinning clock wise. That's the result of positive and negative charges behavior in a vortex.

@nitishchauhan8655 8 жыл бұрын

you have a lot fun doing that don't you

@MrClips11 8 жыл бұрын

+Nitish Chauhan Physics? Yeah, because it coherently explains the Nature of Existence.

@nitishchauhan8655 8 жыл бұрын

dude do you just say shit and hope people won't understand that everything you write is complete bonkertown?

@prateekchauhan732 9 жыл бұрын

cool

@GTSRBOY 14 жыл бұрын

@cheese0cake Right hand rule relates to Protons, conv current deals with protons. If you use left hand rule, your dealing with electron flow

@Damla196 10 жыл бұрын

Jasman Gill, left hand rule is different..

@hardikvyas1948 7 жыл бұрын

We assume mu (U¡=4pi * 10^-7 T m/A

@trinity1969 3 жыл бұрын

Also, did you know we can create charge through magnetic field because of induction?

@Max11551 16 жыл бұрын

Sal could you (or maybe someone else who knows) tell me where I can get that TI85 emulator? Is it commercial?

@samisarwar2956 3 жыл бұрын

If the subtitle were in English, it would be easier to understand, please consider that!

@oO-point-Oo 2 жыл бұрын

Can i find M permeability in casio fx-991ES plus ???

@noneofurbusns3139 8 жыл бұрын

first rule of right hand, you can also imagine yourself opening a bottle of water for example in a certain direction in goes up..

@zaidachmed868 6 жыл бұрын

None ofurbusns ya thats known as screw rule

@hayafatima3190 5 жыл бұрын

outstanding nd easily digestable example of a bottle

@RamisaAnjum 5 жыл бұрын

What will happen if I place a magnet in this kind of magnetic fields?

@jasondove2647 9 жыл бұрын

is it bad if i watch these for fun...

@roneyandrade6287 7 жыл бұрын

NO NEVER THINK THAT!

@jinjin7594 6 жыл бұрын

Jason Dove yes

@AnnSnowfrost 6 жыл бұрын

That's great! What makes you think it's bad to watch them for fun?

@afif4738 5 жыл бұрын

Yes, nerd

@mustafahashimkhan 13 жыл бұрын

What is this "mu" that looks like a "u'!! you rock sal

@taters1123 10 жыл бұрын

You sound like Mircrosoft Sam. But you're awesome.

@0NicoleR0 6 жыл бұрын

the constant is 1.26 x 10^-6 and pi is 3.14 how then are you getting a repeated 1.3333? I plugged in those numbers and got 1.19 x 10^-7

@mihiro271 12 жыл бұрын

one question is there a symbol x in circle denotes inwards whiole the . in circle denotes outward curent

@rajarshi1432 4 жыл бұрын

Yep

@faizakhan3338 10 жыл бұрын

good job..

@sabreen446 7 жыл бұрын

please i want to know why the magnetic field created around a wire

@AhmadKhan-sp3qb 7 жыл бұрын

sa breen no one knows this uptill now.faraday when asked about this said it was a miracle

@NiiGHTBURN 8 жыл бұрын

So cool thank you so much sir

@haniefsofi 4 жыл бұрын

The result you used is only true when the wire is infinitely long. You Should have mentioned that.

@miidy1102 5 жыл бұрын

just fyi Uo = 4pi × 10^-7

@Belmior 6 жыл бұрын

Hmm if a coil is producing this field, how can I use another coil to pick this magnetic field up? I don't want to receive the electric field but the magnetic

@mistersinister2043 8 жыл бұрын

What is the physical reason why the field spins counterclockwise to the current's direction?

@ccmiint 8 жыл бұрын

+MisterSinister A current in a wire creates a magnetic field. Using a compass you can see that field and find its direction. To help figure out the direction Ampere has created the right hand rule. It's just a standard rule so everyone follows the same convention and agrees on direction. Check out right hand rule on wikipedia for a demo.

@mistersinister2043 8 жыл бұрын

ccmiint Yes, I understand it is merely for convention now.

@AndyU96 8 жыл бұрын

+MisterSinister I believe it is something no human knows why. We just observe the thing. ccmint's answer isn't answering your question in a sufficient way.

@mistersinister2043 8 жыл бұрын

EmirhanMW2 It is just convention, meaning there is no actual reason. It's just so everyone uses the rule the same, like labeling one direction left and one direction right, even though there is no real difference.

@AndyU96 8 жыл бұрын

+MisterSinister Excuse me but, as matter apparently doesn't have it's own mind, then it actually matters whether a current carrying wire throws you counter-clock wise, or clockwise. A person should ask, why does it go counterclockwise, and not the other way, isn't it the same thing? I don't think it is a 'convention', but rather, an observation.

@superandy456 12 жыл бұрын

On the website this is embeded on its only in 360p but here its only in 240p it makes no sense. :S

@jasmangill3082 10 жыл бұрын

We were taught at school it left-hand rule lol

@cullum14 13 жыл бұрын

@Ardi1589 i think it is

@cullum14 13 жыл бұрын

@Ardi1589 yeh i think so

@Chelsea-gs7qj 7 жыл бұрын

I assumed there wouldnt be a video on this because of the black platform and lack of hands..I stand corrected

@assylkentaukenov4565 4 жыл бұрын

watched

@MrMereum 6 жыл бұрын

Uo=4pi*10^-7

@PhanyMany 11 жыл бұрын

I thought you're supposed to use your left hand for wires??

@animeshmondal1208 8 жыл бұрын

Does it matter if the current is carried by holes or electrons? The direction of the field would still be the same? I know current direction would be the same, I am just wondering if this theory is valid for both cases.

@Legolas0292 9 жыл бұрын

I have a doubt whenever I try to define the direction of the magnetic field B: in the wire's plane the direction would be k (defining k as a unit vector that comes out of the page). But if I want to know the direction at all points, should I define a unit angular vector in cylindrical coordinates?

@quitejaded 16 жыл бұрын

Damn, I discovered your videos in the middle of the summer semester and I wasn't able to catch up. I just finished my final yesterday. I wish I found you sooner. But atleast I'll have you for Calc2, Economics, and Linear Alebra, right? RIGHT? :(

@vamshidharkarra6974 4 жыл бұрын

Bla bla bla