Courses on Khan Academy are always 100% free. Start practicing-and saving your progress-now: www.khanacademy.org/science/p... Introduction and intuition for flux and magnetic flux.
Sal is the best instructor ever. I have watched all his math and physics videos and NOBODY can teach like he can...and he is an artist, too, so his diagrams are great, too.
Please do a video on flux density, and also the difference between B and H field? :p Anyway, great video once again. My teachers this year have been absolutely awful (the books weren't any better as they were written by them), and I cannot express how grateful I am for having been born in a time with the Internet, where free knowledge - WELL explained knowledge - is available to anyone. I have always been something of an autodidact or self-directed learner, and I have always done well in school. However, these last past years I have lost much faith in the education system. However, I still like to learn - just not in school anymore, I honestly dread it - and because of people like you (and others, like DrPhysicsA or Ben Eater and many, many more), this has not only become possible, it almost has become an addiction, a necessity to me. When I watch your videos I feel like understanding almost everything immediately, and in a way where I suddenly re-remember the importance and greatness in these discoveries of our physical world, and I finally feel the true spirit of learning again. Your website is a sanctuary, a place where knowledge and learning aren't related to your gender, your age, your intelligence, your interests in pleasing teachers or whatever. It's just.... pure learning, raw naked. Without biases, without anyone judging you for anything, without anything else. And that's how it should be. Everything I have done >really< well in school has started with you. I will never have more respect for people like I have for people like you. I have no doubt that I will continue learning after my graduation - but this time, for real. Without wasting time on doing stupid stuff to please the teachers and the 'system'. So once again: truly, thank you.
I normally never comment on any UA-cam video but this one is just amazing. I remember watching your video about spring constant when I was a freshman and now I'm 2 months away from graduating high school, and I would've never made it without you. Thank you sal, thank you dearly.
So much better than the 5 second glossed over definition on Bozeman science which was something along the lines of "it's how much a conductive material reacts to a magnetic field. Like how you react to sunlight." And that was literally it. It was in the video on induction. I got completely lost after that and had to seek out other resources.
what an amazing video it was....though i knew about the magnetic flux before but it widens my previous knowledge so very much.....thanks sal khan ....proud to be a bangladeshi
We all know this is an extraordinary man and channel. But this video just blew me away, it sounds simple now but it looked crazy before, that is teaching perfection.
Working on it. I'll have a video up in a couple of weeks explaining the theory behind a flux capacitor. It's a follow up video to this one I made... ua-cam.com/video/GWiKGiK_iQI/v-deo.html If you're a fan of BTTF, and you're still reading responses to a comment you made a year ago, I think you'll like it.
A limited area of knowledge or Endeavour to which pursuits, activities and interests are a central representation held to a concept of physical theory. In this way, a field is defined by the distribution of a physical quantity, such as temperature, mass density, or potential energy y, at different points in space. In the particularly important example of force fields, such as gravitational, electrical, and magnetic fields, the field value at a point is the force which a test particle would experience if it were located at that point. The philosophical problem is whether a force field is to be thought of as purely potential, so the presence of a field merely describes the propensity of masses to move relative to each other, or whether it should be thought of in terms of the physically real modifications of a medium, whose properties result in such powers that are, liken to force fields, having potentially pure characterized by their means of dispositional statements or conditionals, or are they categorical or actual? The former option seems to require within ungrounded dispositions, or regions of space that differ only in what happens if an object is placed there. The law-like shape of these dispositions, apparent for example in the curved lines of force of the magnetic field, may then seem quite inexplicable. To atomists, such as Newton it would represent a return to Aristotelian entelechies, or quasi-psychological affinities between things, which are responsible for their motions. The latter option requires understanding of how forces of attraction and repulsion can be grounded in the properties of the medium. The basic idea of a field is arguably present in Leibniz, who was certainly hostile to Newtonian atomism. Despite the fact that his equally hostility to action at a distance muddies the water. It is usually credited to the Jesuit mathematician and scientist Joseph Boscovich (1711-87) and Immanuel Kant (1724-1804), both of whom was influenced by the scientist, Michael Faraday (1791-1867), with whose work the physical notion became established. In his paper on "The Physical Character of the Lines of Magnetic Force" (1852). Faraday was to suggest several criteria for assessing the physical reality of lines of force, such as whether they are affected by an intervening material medium, whether the motion depends on the nature of what is placed at the receiving end. As far as electromagnetic fields go, Faraday himself inclined to the view that the mathematical similarity between heat flow, currents, and electromagnetic lines of force was evidence for the physical reality of the intervening medium.
Hey and what if you increase the area but to towards a region where magnetic field lines didn't exist? Logically i would say the flux won't change, but wouldn't it increase by the equation ABcos theta? I appreciate a quick response
Is there a definition for a SINGLE line of flux? For example, this would allow us to state exactly how many LINES of flux passes through a square meter in a uniform magnetic flux field of, say, one "Tesla" perpendicular to that flux field. THANKS FOR, YET ANOTHER, GREAT VIDEO!!
You've been helping with through math and science since I was a wee little guy and this is the last video in the electrical physics playlist so there arn't any more videos here for me. Thanks so much man you've saved my life (test grades) its been good learning from ya (:
I'm not clear why an increase in speed means a higher flux? 2:50 you say higher speed means "more things going through that surface" but is that true, where can I learn the explanation for that? If the density is the same, and you plunk a net down, the "things" that go through, go through faster, but do more "things" go through?
Pleaser anybody help me. Is the magnetic flux, the density of the magnetic vetors? or the size of the vectors? Or a product of both? Sal Khan, mentioned that the flux is how many are perpendicular to the surface. but if you tilt the surface, then no vectors are going to be perpendicular to the surface.
Flux is defined as flow of something per unit area per unit time, so when stretching the "net" to increase area, flux can be reduced. So it's about how we define flux. Great video. Pls make some video explaining types of magnetic material. Thanks.
Assuming the flow per unit time is constant and the amount of flow of the material is the same before stretching the "net". Then yes, the flux is reduced.
I think magnetic flux & magnetic field are 2 different entities. Magnetic flux is a scalar qty. measured by its density while magnetic field is a vector qty. shown by line with arrow. Both, flux & field follow inverse sq. law. A magnetic pole has flux around it. Magnetic field which is force field appears only when flux of one pole interacts with flux of other pole. Since there is no monopole magnetic flux & magnetic field co-exist around a magnet. Change in flux density & motion of flux produce all forces & motions.
Might as well add electrical induction into this lesson. The amount of magnetic flux that is in relative motion next to a conductor induces voltage onto the conductor. This is how we generate electricity.
The rain has abated and pollutants that were in the air have been grounded. Things around me can be seen more clearly now, but as electrons in obscene amounts whiz by me, through copper wires, as the power meter counts them over time as I listened to the sound of the electric fan in the heater blowing warmed air towards my person to reduce the chilly sensation of the cooler oxygen atoms take up the heat given up by my body, as I let the video on the topic of magnetic flux play to its end, I was left wondering - What is magnetic flux? Magnetic flux can be likened to water flow in a river, fed by tributaries upstream. Flux can be imagined to be flowing as tributaries carrying water to a stream. The deeper the stream, the greater the pressure at depth. Magnetic flux condenses with the greater number of flux lines of force, making a greater strength of magnetic attraction and repulsion. Through the air, flux lines tend to separate, but when channelled through a piece of iron or a metal bar the flux lines consolidate in the given metal, leaving no loose ends in the flux field to go astray, but they can be made to follow the desired path. I am the original concept design creator of what I believe has later become used in the design of the Tesla EV motor, so I considered the explanation given of magnetic flux to be a lot more confusing for people new to the subject than it needed to be.
I'm so confused because if you calculate the flux, and you apply gauss law in the magnetic field, it gives you the divergence of the magnetic field, which we know is zero because of the propriety of magnetic fields, please someone explain me what am I missing
Electric current is the same as the change in charge over time (I=Q/t) and charge being the number of electrons flowing multiplied by the charge of a single electron, also called an "elementary charge" (Q=n*1.6*10^-19) Q = Charge n = Number of electrons 1.6*10^-19 = The charge of a single electron (One elementary charge) I = Current t = Time You can think of electric flux in the same way as Sal explained in the example with airflow. Electric flux is the number of force vectors flowing through a given area over a certain time interval. And the force vectors would then be caused by electrons instead of air particles. Hope this helped! Edit: typo
Air "Gradient" , like in image editing gray scale from full white( max density , to gray , lightly dense ) . Read book ISBN : 0-07-027406-1 "Engineering Electromagnetics" 1989 McGraw-Hill . page 45 , 47 , 52 . Streamlines or Flux Lines , or Direction Lines . "Flux" is a very old-time word , circa 1350 to 1400 by now , Flux is in the public domain . All done in Europe . To get a more complete definition of Flux , look it up in a dictionary ( i did ) . Flux isn't just used with electrical phenomena . The above book does discuss how Flux is used to describe the visual interpretation of an equation of a family of curves . When working with magnetism , the Flux lines would be called: Magnetic Flux . If the equations were modeling Electric Fields , the Flux lines ( Streamlines ) would be of Electric Flux . "Flux" ,...Flow lines , visual depiction of an equation . Electromagnetic Field Theory is difficult . 1600 to 1899 about 300 years of European R&D . It was all done in Europe . Mostly France , England , Germany , not necessarily in that order .
we need more electromagnetism videos
+Castor Pollux Agreed!
facts
you have a true gift of teaching
True..
the way he visualizes those 3D image just mind blowing for me
I had to comment that you wrote an "x" at 0:15 and it's the prettiest "x" I've ever seen. Also the vid is awesome so...
Hahaha..
It's been two years you have commented, I hope after seeing this you will feel nostalgia 😁. You will remember your those days and smile (hopefully)
@@Godl_Damon thats sweet
@@unimaginableboi7164 😁
@@Godl_Damonyou are soo sweet ❤ and it's also been two years since you commented 😂 I hope you'll feel nostalgia whenever you see this
Khan Academy is wonderful and it's probably helped me wrap my head around more concepts than I would care to admit. Wonderful library of knowledge
If we had more professors like this, more people would be in engineering and physics!
Thankyou
We need more physics videos. Good to see that there's gonna be more coming out.
Sal is the best instructor ever. I have watched all his math and physics videos and NOBODY can teach like he can...and he is an artist, too, so his diagrams are great, too.
Says he will give an intuition for magnetic flux; gives an intuition for magnetic flux. Solid video.
Please do a video on flux density, and also the difference between B and H field? :p Anyway, great video once again. My teachers this year have been absolutely awful (the books weren't any better as they were written by them), and I cannot express how grateful I am for having been born in a time with the Internet, where free knowledge - WELL explained knowledge - is available to anyone. I have always been something of an autodidact or self-directed learner, and I have always done well in school. However, these last past years I have lost much faith in the education system. However, I still like to learn - just not in school anymore, I honestly dread it - and because of people like you (and others, like DrPhysicsA or Ben Eater and many, many more), this has not only become possible, it almost has become an addiction, a necessity to me. When I watch your videos I feel like understanding almost everything immediately, and in a way where I suddenly re-remember the importance and greatness in these discoveries of our physical world, and I finally feel the true spirit of learning again. Your website is a sanctuary, a place where knowledge and learning aren't related to your gender, your age, your intelligence, your interests in pleasing teachers or whatever. It's just.... pure learning, raw naked. Without biases, without anyone judging you for anything, without anything else. And that's how it should be.
Everything I have done >really< well in school has started with you. I will never have more respect for people like I have for people like you. I have no doubt that I will continue learning after my graduation - but this time, for real. Without wasting time on doing stupid stuff to please the teachers and the 'system'.
So once again: truly, thank you.
I normally never comment on any UA-cam video but this one is just amazing. I remember watching your video about spring constant when I was a freshman and now I'm 2 months away from graduating high school, and I would've never made it without you. Thank you sal, thank you dearly.
I decided to start powder coating as a hobby in my spare time. Faraday’s law came up, which lead me here. I enjoy you way of explaining, thank you.
So much better than the 5 second glossed over definition on Bozeman science which was something along the lines of "it's how much a conductive material reacts to a magnetic field. Like how you react to sunlight." And that was literally it. It was in the video on induction. I got completely lost after that and had to seek out other resources.
Thank you this is crystal clear!
what an amazing video it was....though i knew about the magnetic flux before but it widens my previous knowledge so very much.....thanks sal khan ....proud to be a bangladeshi
We all know this is an extraordinary man and channel. But this video just blew me away, it sounds simple now but it looked crazy before, that is teaching perfection.
@nishitha sri great minds think alike! lol
Sal, please do a series on Maxwell's equations with all the calculus.....
how awesome would that be :/
Thanks! This finally helps me to understand what flux is!
Excellent explanation! I had to learn flux to help my daughter and this video was extremely helpful!
bless your soul! I’m glad your daughter has you to help her!
I want to know how to make a Flux Capacitor
Jio Salcedo if only you knew; how easy it really Is to make .... :/. You need God in the equation to ever even be able to fathom it.
Working on it. I'll have a video up in a couple of weeks explaining the theory behind a flux capacitor. It's a follow up video to this one I made... ua-cam.com/video/GWiKGiK_iQI/v-deo.html
If you're a fan of BTTF, and you're still reading responses to a comment you made a year ago, I think you'll like it.
@@TwoWrights 2 yrs now
Maddiee K I know. I’m awful. I am still working on it. The idea has grown a little bit.
@@TwoWrights haha i meant more that I was totally ready to view it even 2 yrs after your comment
Your videos explain everything I need and want to know. Really, I'm beginning to like many subjects because of your videos.
UA-cam has best tutor and best distraction too lol 😂❤❤
Thank you so much!! You can teach something more clearly in 10 minutes than my professor can in two hours....
I have to agree with that.
Another excellent introduction
Sir you got a thumbs up from me for your every video...keep up the good work...
So is magnetic flux density the density of a part of an electromagnetic field passing through a normal surface?
Exactly the video I needed. Thanks! : D
Dude you explain really great!!!!!
that was so helpful,thanks a lot
Wow 🤩 u are amazing at teaching sir I got now how that formula came out
This really helps! Thank you!
hi, so is it correct to say that the magnetic flux means the relation of the magnetic strength trough an specific area ?
very helpful , thank you
very useful :) im highly grateful ^_^ thanks
Thanks a lot Mr. Khan.
the best video. thank you
Perfect, thank you sir
A limited area of knowledge or Endeavour to which pursuits, activities and interests are a central representation held to a concept of physical theory. In this way, a field is defined by the distribution of a physical quantity, such as temperature, mass density, or potential energy y, at different points in space. In the particularly important example of force fields, such as gravitational, electrical, and magnetic fields, the field value at a point is the force which a test particle would experience if it were located at that point. The philosophical problem is whether a force field is to be thought of as purely potential, so the presence of a field merely describes the propensity of masses to move relative to each other, or whether it should be thought of in terms of the physically real modifications of a medium, whose properties result in such powers that are, liken to force fields, having potentially pure characterized by their means of dispositional statements or conditionals, or are they categorical or actual? The former option seems to require within ungrounded dispositions, or regions of space that differ only in what happens if an object is placed there. The law-like shape of these dispositions, apparent for example in the curved lines of force of the magnetic field, may then seem quite inexplicable. To atomists, such as Newton it would represent a return to Aristotelian entelechies, or quasi-psychological affinities between things, which are responsible for their motions. The latter option requires understanding of how forces of attraction and repulsion can be grounded in the properties of the medium.
The basic idea of a field is arguably present in Leibniz, who was certainly hostile to Newtonian atomism. Despite the fact that his equally hostility to action at a distance muddies the water. It is usually credited to the Jesuit mathematician and scientist Joseph Boscovich (1711-87) and Immanuel Kant (1724-1804), both of whom was influenced by the scientist, Michael Faraday (1791-1867), with whose work the physical notion became established. In his paper on "The Physical Character of the Lines of Magnetic Force" (1852). Faraday was to suggest several criteria for assessing the physical reality of lines of force, such as whether they are affected by an intervening material medium, whether the motion depends on the nature of what is placed at the receiving end. As far as electromagnetic fields go, Faraday himself inclined to the view that the mathematical similarity between heat flow, currents, and electromagnetic lines of force was evidence for the physical reality of the intervening medium.
awesome explaination
Hey and what if you increase the area but to towards a region where magnetic field lines didn't exist? Logically i would say the flux won't change, but wouldn't it increase by the equation ABcos theta? I appreciate a quick response
if theoretically you were to put it in a region where there is no magnetic field the that would mean B=0 so no magnetic flux for you hehehhehe
amazing presentation. a 6 year old could understand flux with your video. well done
Is there a definition for a SINGLE line of flux?
For example, this would allow us to state exactly how many LINES of flux passes through a square meter in a uniform magnetic flux field of, say, one "Tesla" perpendicular to that flux field.
THANKS FOR, YET ANOTHER, GREAT VIDEO!!
Thanks for explaininf flux. I finally got a solid definition for it :D
Amazing, I finally understand. So helpful with the air analogy
شكرا بجد شكرا انا هدعيلك😍😄
what is the name of the application !? and thanks for your great method of teaching
You've been helping with through math and science since I was a wee little guy and this is the last video in the electrical physics playlist so there arn't any more videos here for me. Thanks so much man you've saved my life (test grades) its been good learning from ya (:
I'm not clear why an increase in speed means a higher flux? 2:50 you say higher speed means "more things going through that surface" but is that true, where can I learn the explanation for that? If the density is the same, and you plunk a net down, the "things" that go through, go through faster, but do more "things" go through?
Pleaser anybody help me. Is the magnetic flux, the density of the magnetic vetors? or the size of the vectors? Or a product of both? Sal Khan, mentioned that the flux is how many are perpendicular to the surface. but if you tilt the surface, then no vectors are going to be perpendicular to the surface.
Very useful!
Thank you brother
Thank you for visualising flux for me
Khan! It is great, thanks, I want more physics video :))
thank u so much
Thanks 👍
Really helpful thank u. would love more on electromagnetism
Eieueieue
Flux is defined as flow of something per unit area per unit time, so when stretching the "net" to increase area, flux can be reduced. So it's about how we define flux. Great video. Pls make some video explaining types of magnetic material. Thanks.
animesh mondal yes agreeable ,absolutely right
I think you mean when stretching the "net" to increase area, flux is increased?
Assuming the flow per unit time is constant and the amount of flow of the material is the same before stretching the "net". Then yes, the flux is reduced.
animesh mondal:
Flux=“flow of something”*Area / time.
How can flux decrease with increase in area?
Nghia: I’m as confused as you lol.
Thank u this is amazing 😃
I think magnetic flux & magnetic field are 2 different entities. Magnetic flux is a scalar qty. measured by its density while magnetic field is a vector qty. shown by line with arrow. Both, flux & field follow inverse sq. law. A magnetic pole has flux around it. Magnetic field which is force field appears only when flux of one pole interacts with flux of other pole. Since there is no monopole magnetic flux & magnetic field co-exist around a magnet. Change in flux density & motion of flux produce all forces & motions.
Thank you sir
thank you
oh man, where were you in 2005? i've been looking the best analogy for this flux definition for years. thank you my man
Why do we use "phi" to show flux?
Might as well add electrical induction into this lesson. The amount of magnetic flux that is in relative motion next to a conductor induces voltage onto the conductor. This is how we generate electricity.
+TKO593 isn't this what we're talking about here, or what is the current we are talking about here?
thank you man thank you so much
Kindly, make a video on CT PT (CURRENT TRANSFORMER, POTENTIAL TRANSFORMER). could you?
Useful ...
A lot helpful
Great thanks
Thanks .
Thank you!!
Thanks a lottt
great video
Where is part 2
Helpful
Those drawings were beautiful
what app is he using?
God bless you
Salute from bottom of my 💜❤
Seriously. I love you
thanks
Thank you so much mr. khan! (mr. sal)
Great video but those swallowing sounds near the end were almost too much for me to keep my attention
Great vid
superb
The rain has abated and pollutants that were in the air have been grounded. Things around me can be seen more clearly now, but as electrons in obscene amounts whiz by me, through copper wires, as the power meter counts them over time as I listened to the sound of the electric fan in the heater blowing warmed air towards my person to reduce the chilly sensation of the cooler oxygen atoms take up the heat given up by my body, as I let the video on the topic of magnetic flux play to its end, I was left wondering - What is magnetic flux? Magnetic flux can be likened to water flow in a river, fed by tributaries upstream. Flux can be imagined to be flowing as tributaries carrying water to a stream. The deeper the stream, the greater the pressure at depth. Magnetic flux condenses with the greater number of flux lines of force, making a greater strength of magnetic attraction and repulsion. Through the air, flux lines tend to separate, but when channelled through a piece of iron or a metal bar the flux lines consolidate in the given metal, leaving no loose ends in the flux field to go astray, but they can be made to follow the desired path. I am the original concept design creator of what I believe has later become used in the design of the Tesla EV motor, so I considered the explanation given of magnetic flux to be a lot more confusing for people new to the subject than it needed to be.
Salute man!
I'm so confused because if you calculate the flux, and you apply gauss law in the magnetic field, it gives you the divergence of the magnetic field, which we know is zero because of the propriety of magnetic fields, please someone explain me what am I missing
i would explain if you weren't a kpop fan
Thank you, thank you, thank you, thank you so much. Sir.
Sir I want to know that why a magnetic flux in closed loop is 0 as defined by gauss law of magnetic flux
Kyunki koi chiz close hai toh usse magnetic fields lines kaise pass through hongi
After all magnetic flux is the amount of magnetic field lines passing through a surface in a given amount of time ( pls correct me if i am wrong )
Btw are you a jee aspirant ?
Why energy is no needed.to maintain a magnetic flux in a magnetic circuit
Why ?
goshdamn this is so much better than my teachers way of explaining it
Good
HatsOff
How is electrical flux different from electrical current?
Electric current is the same as the change in charge over time (I=Q/t) and charge being the number of electrons flowing multiplied by the charge of a single electron, also called an "elementary charge" (Q=n*1.6*10^-19)
Q = Charge
n = Number of electrons
1.6*10^-19 = The charge of a single electron (One elementary charge)
I = Current
t = Time
You can think of electric flux in the same way as Sal explained in the example with airflow. Electric flux is the number of force vectors flowing through a given area over a certain time interval. And the force vectors would then be caused by electrons instead of air particles. Hope this helped!
Edit: typo
Erik H: Nice explanation, you deserve a like from me.
Air "Gradient" , like in image editing gray scale from full white( max density , to gray , lightly dense ) .
Read book ISBN : 0-07-027406-1 "Engineering Electromagnetics" 1989 McGraw-Hill .
page 45 , 47 , 52 . Streamlines or Flux Lines , or Direction Lines .
"Flux" is a very old-time word , circa 1350 to 1400
by now , Flux is in the public domain . All done in Europe .
To get a more complete definition of Flux , look it up in a dictionary ( i did ) .
Flux isn't just used with electrical phenomena .
The above book does discuss how Flux is used to describe the visual interpretation of an equation of a family of curves .
When working with magnetism , the Flux lines would be called: Magnetic Flux .
If the equations were modeling Electric Fields , the Flux lines ( Streamlines ) would be of Electric Flux .
"Flux" ,...Flow lines , visual depiction of an equation .
Electromagnetic Field Theory is difficult .
1600 to 1899 about 300 years of European R&D . It was all done in Europe . Mostly France , England , Germany ,
not necessarily in that order .
so is current sorta like a type of flux in relation to flow of electrons then?
I guess, yeah.
got it!!!! thank you
Colorblind people watching Khan Academy:
Wow... I really just learned something that I haven't been able to understand all semester in 10 minutes