I'm 37 and going back to college, bro... very well explained! I mean I had to watch the video couple of times, but well worth listening too! I look forward to watching all your video... send me a link or something! I'm gonna recommend this to my class mates!
I used Khan Academy to learn math in my first college semester so I could skip two classes that I should take by just taking two proficiency tests. It made me save thousands of dollars and 1 year of time! I still come to get helps here at times. I love free videos, since I'm a broke college student, but I feel like donating a bit to make the number grow. So I did, and then it is 3,380.00 now! It's so transparent! I respect people who spread good knowledge all over the world!
You have know idea how helpful this is for my AP test. My teacher has barely started E&M and he's rushing through it at light speed-too fast for me to understand.
Waw this is so well made, the whole video I was wondering when he was gonna talk about capacitance then at 11:10 everything came together and made sense. What a build-up !
Brilliant! Got a distinction in physics cause of his teaching. I owe you one sir. ur the reason for my A-grades :D (Sometimes people makes things so complicated although its relatively SIMPLE)
To footlooseontherun: True, electrons move toward the positive side. However, when Benjamin Franklin chose the negative and positive conventions, he got them mixed up. For ease and convenience, we keep the traditions. Yes we could switch the positives and negatives so flow follows electrons, but the math works either way, and it's easier to keep as is.
@irondmax It's because we assume electric field lines are the direction in which a positive charge will move. A +ve charge next to a +ve plate will repel, and a +ve charge next to a negative plate will attract towards the -ve plate. Hence they're the same direction.
k=coulomb's constant, approx 8.988x10^9 Nm^2/C^2 epsilo naught (Permittivity of free space) = approx 8.854x10^-12 F/m, or 1/(4*pi*k) These are different constants.
Flight1510-That sounds exactly like my 12th grade AP Physics teacher too! What is up, they expect us to come into their class knowing what they know already or sumthin.
love your video.....going to whatch more later.... i have a question.........why would the neg power go the same way as the pos power? makes no sence? if you have a video of this please direct me thanks
nice video. However, working with vacuum tube theory it is the electron that is set in motion in a circuit. It gets messy when explaining it the other way. Which then becomes it works either way. So should there be a 3rd motion version it makes no difference it just moves? 🤣 thanks, great info. 😎
Shouldn't we get a total for 0 for the electric field since one of the plates has a negative charge and the other is positive? Need some help understanding this. Thanks!
Because the electric field of a negative point charge points toward the point charge. It would be pointing away from a positive point charge. This is not like positive and positive repel each other, this is another concept. We are talking about electric fields here, not the charges.
why conductors are use to make capacitor? Can we make capacitor using insulators? What happened if we use 2 parallel insulators instead of 2 parallel conducting plates
If you connect a wire around the outside of the plates instead of the inside, how can a charge carrier move away from one plate of the same charge sign (decreasing it's voltage in respect to it), but then come close to it again to arrive at the other plate. Is work conserved because as it moves away from one plate of the same sign, it gains voltage in respect to the other? In the ideal example of the infinite plains, do fields cancel out in the area not between them? In real life since field strength diminishes with distance, and V=E*d, is voltage independent of distance? Maybe I should look more intro conservative fields and path integrals.
My bad, if the charge carrier and plate have the same sign, potential is lost with distance. The answer I was looking for is kinetic energy/ inertia. The best way to imagine this is a mountain( the top wold be the + point charge ), a hole (-) and a plain (neutral charge). Considering 0 friction/ resistance, the total work done by a sphere(POSITIVE charge carrier) of mass m(charge) guided by a slide(wire) ONLY CHANGES with a difference in height traveled(distance traveled by charge carrier between the opposite charges) between the mountain top and hole bottom. If the slide is circular connecting those points, you could let the sphere fall down the mountain and intro the hole (all potential energy transformed intro kinetic), and then go back up to the mountain top(maximum potential energy, 0 kinetic), and the whole thing would loop. Same goes for a charge in a wire loop between the opposite point charges. Of course both the sphere and charge carrier would need a initial velocity, which would be conserved as well.
You should really make a video on potential intuition, I think that would help many people. Also, I've seen many of your videos and I can say that these about electricity, even though they are good, are the worst I've seen from you. You got me used to really good videos and these were just kind of dissapointing.
Please help! What would've happened to the electric field if I had had two parallel plates but both with a positive charge? If one of the plates (plate #1) have a larger positive charge than the other, does it's electric field then cancel out the other's (plate #2) electric field, so that the net result is that we get an electric field pointing from plate #1 to plate #2 but weaker than if we would have just had en electric field from plate #1 with no presence from plate #2? In other words, does plate #2 in this scenario act as the negative end between the two positevly charged plates?
when there are two positive plates in parallel, the electric field vector will be 0, as the electrical force that each plate produces on a charge will be anulated by the other
I really wish I could reply to footlooseontherun and tell him that electric field lines are only drawn from the perspective of a positive test charge, but I can't because UA-cam is retarded. Thanks UA-cam.
Reading the comments gives me a strange feeling . Some of them belong to 12 yrs ago . Life passes quickly . Maybe one day someone will read my comment and says; look how old this comment is or maybe i would be dead by the time
To get the video to work, click somewhere further on in the stream, then go back to the beginning.
genius
Thanks!!!!!!!!
Well spotted, thanks!!
Thank you! I thought there was something wrong with my internet! Khan Academy, please fix this soon :)
Zach Hoskins Genius...
I'm 37 and going back to college, bro... very well explained! I mean I had to watch the video couple of times, but well worth listening too! I look forward to watching all your video... send me a link or something! I'm gonna recommend this to my class mates!
Hi kurkie . May i ask you a question ?
Hi guys are you alive ?
@@youtubeessentials2996 dude it was 12 years ago 💀
@@emiryusufkaragoz14 years ago 😮😮
OH GOD,, I understand this... THIS IS AMAZING. The world now makes sense.
I used Khan Academy to learn math in my first college semester so I could skip two classes that I should take by just taking two proficiency tests. It made me save thousands of dollars and 1 year of time! I still come to get helps here at times. I love free videos, since I'm a broke college student, but I feel like donating a bit to make the number grow. So I did, and then it is 3,380.00 now! It's so transparent! I respect people who spread good knowledge all over the world!
You have know idea how helpful this is for my AP test. My teacher has barely started E&M and he's rushing through it at light speed-too fast for me to understand.
studying for the MCAT and your voice is so soothing so thank u
Waw this is so well made, the whole video I was wondering when he was gonna talk about capacitance then at 11:10 everything came together and made sense. What a build-up !
2:50 "assuming the is d isn't too big" ahahhaha...
Chris Gloria the moment I heard that I headed down to the comments expecting at least SOMEONE to have noticed and commented about it 😂
Brilliant! Got a distinction in physics cause of his teaching.
I owe you one sir. ur the reason for my A-grades :D
(Sometimes people makes things so complicated although its relatively SIMPLE)
Finished school and still watching these videos somehow. Thanks Sal.
how is he so good at drawing on a computer?
Tsvetan Dimoff that's why we can see a cursor on the screen
probably has an art board
Yep, easy.. A Wacom tablet.
We meet again 240p
lmao im dead...
simplicity is the greatest sophistication. Nikola Tesla was the greatest physicist we've had
I'm a physical therapy major and I really don't need physics, but it's required and I couldn't do it without you
I'm an American going to school in Munich at the TUM....
Your videos are saving my college career :)
thanks!
what type of work would this become? what studies is this subject?
IT's A GOOD METHOD FOR STUDENTS
If you click in the video then click back to the beginning the video works
thumbs up so others can see
To footlooseontherun:
True, electrons move toward the positive side. However, when Benjamin Franklin chose the negative and positive conventions, he got them mixed up. For ease and convenience, we keep the traditions. Yes we could switch the positives and negatives so flow follows electrons, but the math works either way, and it's easier to keep as is.
Like this person`s work.
k=coulomb's constant, approx 8.988x10^9 Nm^2/C^2
epsilo naught (Permittivity of free space) = approx 8.854x10^-12 F/m, or 1/(4*pi*k)
pretty good. u should go worldwide in electrical circuitry explanations haha seriously though
this is a superb lecture. thank you
V = integral (0 -> d) ( E*dx) Where E is the electric field, d - the distance. You can derive these formulas by solving this integral.
@irondmax It's because we assume electric field lines are the direction in which a positive charge will move. A +ve charge next to a +ve plate will repel, and a +ve charge next to a negative plate will attract towards the -ve plate. Hence they're the same direction.
k=coulomb's constant, approx 8.988x10^9 Nm^2/C^2
epsilo naught (Permittivity of free space) = approx 8.854x10^-12 F/m, or 1/(4*pi*k)
These are different constants.
"let me do in this colour"
@veteran25 I'm a senior in college and these vids are still saving my arse! Best of luck. :)
Flight1510-That sounds exactly like my 12th grade AP Physics teacher too! What is up, they expect us to come into their class knowing what they know already or sumthin.
They use the same letter for different things often as there are more things than letters.
@veteran25
I'm in the same boat completely, except my situation is caused by an incompetent teacher not teaching us anything
WHAT THE FLUX THIS VIDEO WILL NOT PLAY.
Slightly confusing at first but it all comes together in the last 30 secs or so.
can you please do a video on equipotentials
Your the man Sal.
love your video.....going to whatch more later....
i have a question.........why would the neg power go the same way as the pos power?
makes no sence?
if you have a video of this please direct me
thanks
0:17 * The electric field is *uniform.*
thank you SAL!!!!
its a plane not a line so it has an area and the pi is canceled out with k=1/(4(pi)(8.85E-12))
nice video. However, working with vacuum tube theory it is the electron that is set in motion in a circuit. It gets messy when explaining it the other way. Which then becomes it works either way. So should there be a 3rd motion version it makes no difference it just moves? 🤣 thanks, great info. 😎
Shouldn't we get a total for 0 for the electric field since one of the plates has a negative charge and the other is positive? Need some help understanding this. Thanks!
yup yup
Coulomb's constant!
8.99*10^9
i (think) its the amount of electrons per coulomb.
What a great video
its K all right i read it in a book.
isnt work different with respect to the different charged plates?
assuming 'd' isn't too big. lol!
@Oneill9293 i see thanks.
DC current flow in one direction......is that correct?
thanks again
I DIDN'T COME TO WATCH THE VIDEO! I CAME HERE TO SAY I LOVE YOU AND KHAN ACADEMY
Where did he get the 2 and the Pi in the beginning. It's a uniform line..so should it not be Landa charge/length instead of sigma?
thanks
Why does the negative field move back towards the negative plate and not the positive? since opposite charges should attract.
Because the electric field of a negative point charge points toward the point charge. It would be pointing away from a positive point charge.
This is not like positive and positive repel each other, this is another concept. We are talking about electric fields here, not the charges.
8:42, how did he get the joules? Did he replace couloumbs with joules??
thank you sir
isnt k=1/(4pi E) and not the other way around ?
why conductors are use to make capacitor? Can we make capacitor using insulators? What happened if we use 2 parallel insulators instead of 2 parallel conducting plates
capacitors are used to store electric charge.....to store electric charges we need a conductor
sooooooooooo interesting
great vid as usual. @ devin he has a touch screen. also what happened to 360p and 480p? its 2014.
He uses a graphic tablet and this video was uploaded more than 6 years ago, hence the quaility.
im watching this video in 2022 MYGOD feels like im studying from a fossill *crys*
can u explain abt Wheatstone network of capacitors
♥شكرا
♥thank you
♥ Merci beaucoup
Thank You Sir. Very well explained. Your videos are helping me understand electronics very kwel .
please fix the video cz I can't watch it
it's not a khan academy video if it's not 240p
whats the next video where it is located?
PRO TIP: speed this up 2x and save yourself from seven minutes of him stumbling over words and changing his mind half-way on what he wants to say.
fucking hell i thought i was the only one who did that. he doesnt get to the point AT ALL
at the beginning you assumed that q =1C
what if we didnt take a value there?
Where's that intuitive understanding of voltage ??
Papa did you take all the adderall? Try finishing 1 thought
Actually, the # of electrons per coulomb is either 1.6 or 6.0x10^19
Yo, bro how's life been all these years...?
You practically have to be a rocket surgeon to get some of these videos to work.
Christian Castro "rocket surgeon"??? 😂😂😂 🚀😷
if i m not mistaken capacitance= Q/V
i.e charge/electric potential (?)
help?
geez ignornat. Have you even taken physics before?
Kelvin K is a unit for temperature, but this k is a constant which is equal to 8.99*10^9
If you connect a wire around the outside of the plates instead of the inside, how can a charge carrier move away from one plate of the same charge sign (decreasing it's voltage in respect to it), but then come close to it again to arrive at the other plate. Is work conserved because as it moves away from one plate of the same sign, it gains voltage in respect to the other? In the ideal example of the infinite plains, do fields cancel out in the area not between them? In real life since field strength diminishes with distance, and V=E*d, is voltage independent of distance? Maybe I should look more intro conservative fields and path integrals.
My bad, if the charge carrier and plate have the same sign, potential is lost with distance. The answer I was looking for is kinetic energy/ inertia. The best way to imagine this is a mountain( the top wold be the + point charge ), a hole (-) and a plain (neutral charge). Considering 0 friction/ resistance, the total work done by a sphere(POSITIVE charge carrier) of mass m(charge) guided by a slide(wire) ONLY CHANGES with a difference in height traveled(distance traveled by charge carrier between the opposite charges) between the mountain top and hole bottom. If the slide is circular connecting those points, you could let the sphere fall down the mountain and intro the hole (all potential energy transformed intro kinetic), and then go back up to the mountain top(maximum potential energy, 0 kinetic), and the whole thing would loop. Same goes for a charge in a wire loop between the opposite point charges. Of course both the sphere and charge carrier would need a initial velocity, which would be conserved as well.
crystal clear :) :)
Of course the video doesn't work during finals week.
You should really make a video on potential intuition, I think that would help many people.
Also, I've seen many of your videos and I can say that these about electricity, even though they are good, are the worst I've seen from you. You got me used to really good videos and these were just kind of dissapointing.
You need to study them in engineering class. This is physics :).
Khan I love you
Please help! What would've happened to the electric field if I had had two parallel plates but both with a positive charge? If one of the plates (plate #1) have a larger positive charge than the other, does it's electric field then cancel out the other's (plate #2) electric field, so that the net result is that we get an electric field pointing from plate #1 to plate #2 but weaker than if we would have just had en electric field from plate #1 with no presence from plate #2? In other words, does plate #2 in this scenario act as the negative end between the two positevly charged plates?
when there are two positive plates in parallel, the electric field vector will be 0, as the electrical force that each plate produces on a charge will be anulated by the other
You were correct, it is the net field.
I really wish I could reply to footlooseontherun and tell him that electric field lines are only drawn from the perspective of a positive test charge, but I can't because UA-cam is retarded. Thanks UA-cam.
that actually makes sense, are we talking engineering charges or physics charges?
How did he get E= 2kpiesigma?
every times i hear infinitely charged I keep thinking capacitor
There is terrible mistake in the Arabic subtitle the time from 4:57 to 11:41 does not have subtitle at all please fix it
Tem esse vídeo legendado ou dublado? Não consegui encontrar :/
Subtitled
@veteran25 i'm in your position right now.
XDDDDDDDDD ILY HIS WORK XDDDDDDD
khan whats the deal with some of your videos, this is the third one ive found so far that has stopped working on us
Why did u write Electric field twice in the work formula? ?!!
first for the + ve plate.....than - plate because bth hve charge
greeaaaat
Lolol this comment is from 10 YEARS AGO!!!
Hello 240p my old friend
Electrons actually flow from Negative to Positive but carry on please.
This, I literately cannot understand Gauss's law for the life of me
i think u can, but i m not sure that's right thing to do.
does anyone notice the ghost images or is that just me?
:17 - :26
He's such a spaz...
Reading the comments gives me a strange feeling . Some of them belong to 12 yrs ago . Life passes quickly . Maybe one day someone will read my comment and says; look how old this comment is or maybe i would be dead by the time
Yah literally I was thinking so 😐
@@PW_Rockstar kaise chl ri revision
@@shubhm8639 revision thik h but practice 👎👎
@@PW_Rockstar meri bhi ,
Please fix the video :)
can't watch
wtf was this about -.-" i thought there would be an explanation of how capacitor works and both in AC and DC circuits >
The bad quality is hurting me