Electric potential at a point in space | Physics | Khan Academy 

I'm upset that my education sometimes relies on professors who have phDs, but they don't know how to convey a message across to their students. They are smart, but cannot teach. I need to pass Physics to graduate and I am glad these videos are here to help me to do what my professor can't.

It should be a fundamental human right to have access to this video (and more particularly this teacher)

really, really thanks, this is the best explanation of eletric potential in the entire youtube.

This single video is without a doubt the standard to which all education should be set- the clarity of something that can be so confusing in text or lecture astounds me. Thank you Khan Academy for everything you give students

this explains the. MOST. confusing thing I've ever learned in physics. thank you so much I had a brain explosion.

That's the clearest explanation i've found on youtube! Thanks a lot

Physicists really need to come up with better terminology. Are they purposely trying to confuse us... ?

1:21 "Stick a big ol' charge in here." Why did I start laughing all the sudden?

This is a deadly most wanted technical clearance ever in physics. I was so confused with potential and potential energy and the work done related to them. Now it is clear. I appreciate it very much.

You have no idea, I've been struggling with this concept for so long and I finally get it I just needed it broken down like that! Amazing teacher thanks for the video.

I have been waiting for the longest time for a video on this. THANK YOU!!!

You're actually a life saver.

Our physics book says a lot of things to make physics look fun, but at the end of the day they took all the important stuff out. Thank you very much for the video

I have only one word for this video - AMAZING

Best explanation I ever had just amazing😘

This is all when using a reference point at infinity, if he explained both with a random reference point, this would be the best video ever created...

I need this guy to be my physics teacher😭

This is the best explanation for e potential/potential energy that I have ever seen. I finally understand now

David is the best! Very effective at explaining these complicated concepts

Was struggling a ton with my exercises, but I realized I just didn't get the whole difference between potential and potential energy. Thanks!

Sooooooooo good!! Genius!

This video really makes me to know about what is electric potential . Thanks sir

so whats the difference in concept between E=V/R and E=F/q

Very difficult topic -- thanks for boiling it down!

Does it matter who does work on it :external force or electric field?I mean,what if there is a negative charge instead positive?

Thankyou very much...Was really confused with the topic...I am able to visualise and grasp the logic behind these terms...😊 It was a wonderful and clear explanation!

This may seem obvious to many but watching this masterpiece was the first time I actually realized that electric potential does NOT follow the inverse square law!

This video cleared all doubts about electric potential...... awesome video

Excellent video, I finally somewhat understood electric potential after months of trying to figure out what it was. Thank you very much, KhanAcademy

It's not magic , just it's clear , and that's what our * educational systems* lack

Very best explanation of electric potential in the entire youtube😘👌👌

Thanks a lot you save my life!

The world's best teacher thanks

not sure if i should be sad or happy that youtube is better then most education system.....

Good job done

very informative,easy to understand and crisp video.Very good work here.Thanks a lot!

Ok I had tears in my eyes 👀 for the love of physics and first time I understand this.

Thank you! This visual makes way more sense than a paragraph of info in my textbook!

those dots are trippy >

What screen recording software do you use? I would like to know a good one that allows me to pause recording.

wow this is a great explanation !

You teach magical

THANK U

Thank you so much, i've been struggling to understand this concept for 2 days!

Thanks David SantoPietro. Very Cool!

Bonjour est-ce que cette vidéo existe en Français , c'est la seul notion que j'ai du mal à comprendre (le potentiel Electrique ) et qui est en anglais, si on ne maîtrise pas l'anglais c'est difficile de bosser sur un sujet dont on a déjà un peu de mal , merci .

This video is EPIC😎. Whenever I get a doubt in this topic, I come here and never go back disappointed😊😊

amazing explanation

After a long search, I decided to watch this video to see what the fuck Electric Potential was so I wont fail my midterms tomorrow. And I'm glad I did, not only does it explain WHAT this is, but it also explains where the formulas for this come from. Thanks a bunch!

Are you a communications major, because you are an excellent communicator of Electric potential?

Expound on the relationship of Electric Potential between two points in space and Electric Potential value at one point in space.

Man, i love it. And thank you!

Thanks for this amazing video. Very helpful in explaining this topic! Bravo Khan.

WOWWW. I HAVE NEVER SEEN SUCH AN AMAZING VIDEOOOOOOOOOOOO

Thanks a lot sir l've been struggling with this topic that was very effective explanation

Thank you for the video, this helped me out tons!

Speechless. Just just thank you!

Best explanation ever on this topic!

Thank you

absolutely fantatstic video

this video helped me so much, you are a lifesaver!!! thank you!!!!!

A real hero

the man who named this shit will get a name on my death note

Thanks 🎉

Thank you.... Really gives you a better idea....

superb video.....but at 8:50 why did he have to say that it isn't 'r' squared?Wasn't necessary:p

At 1:05 you say the V value at any point without any charge around, would be zero. This makes sense. Then at 1:20 you say to make any point have a V value that is non-zero, all you have to do is place a charge at any point. Then at 2:15, you say if this point (bottom left corner) happened to have a V value of 100 joules/coulomb. This contradicts the comment at 1:05 where you say a point without a charge would have V = 0. But at 2:15, you are referring to a point that doesn’t have a charge (no coulombs) and instead of V = 0, this point has a hypothetical V value of 100 joules/coulomb. How could this point have a V value even though there isn’t any charge at this point?

This explanation is amazing!

man this was like a God sent. our professor glossed over this so hard. It seemed like it was much simpler in class but I was not getting it. thankfully there are people like you out there who can relate and actually tell us why we care about this concept. Thank you

You are the best! Thanks a ton :)

Thank you very much for this beautiful explanation and for all your effort.

thank you sir , it helped me a lot

So nice thanks sir

you're just too good man!!!

This helped so much thank you!

thank you so much!!!

So if you were to place a second charge right on top of Q, the r would be 0, and V would be infinity?

Is the charge being negative or positive gonna affect the calculation?

How does a voltage develop across the unconnected end of a single wire connected to one terminal of a battery and the other terminal? If the battery’s net charge is zero, then for a 12 V battery, one terminal would be at a potential of +6 V with respect to a conductor at infinity, while the other terminal would be at -6 V. At the physical center in the space between the two terminals of the battery, the voltage is zero. If we then connect a small wire to, say, the positive terminal, a few excess point charges will move onto the wire, and that wire will now be at the same potential as the battery terminal: +6 V. The wire will be surrounded by an e-field, and since the lines of electrostatic flux must always terminate upon charges, the wires must possess an excess surface charge. In the above we assumed the net charge of the battery was zero. Supposing that the battery had a net charge. Then how would the charges, potentials and voltage be changed? Before we answer this, it would be instructive to understand Current, the conduction process and Voltage at the fundamental level. Electrostatics and circuits belong to one science not two as in the following two videos: i. ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-REsWdd76qxc.html and ii. ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-8BQM_xw2Rfo.html Returning to our question of the voltage of the single wire connected to one battery terminal, we assume the net charge of the battery was not initially zero. Perhaps someone with rubber-sole shoes carried the battery while walking on a wool carpet or perhaps the battery was charged to -5000 V, and would deliver a tiny spark if touched. In that case one terminal would still be 12 V different than the other terminal, perhaps -5000 V on the positive terminal and -5012 V on the negative. It is not possible in this brief post to discuss in more detail the process of production of the voltage of the single wire without a detailed discussion of the capacitance and potential of single conductors. The last frame References in video #1 lists textbook 4 which discusses these topics comprehensively using a unified approach and provides an intuitive understanding of voltage of a single short and long wire with and without a net charge on the battery.

damn he killed it, that's the best explanation ever

I came across electric potential defined as the amount of work needed to move a charge q to some distance r against(?) the direction of the electric field; hence, V = Er = (kQ/r2) r = kQ/r

Believe it or not, a moving magnet may also generate an electric potential, but such an electric potential depends not just on the position of the magnet but also the velocity of the magnet. Source: "Electromagnetic interactions derived from potentials: charge and magnetic dipole" by Roberto Coïsson

I dont see a problem with Electric potential energy. It is not abstract. It is indeed a potential energy per unit charge. By convention consider a small positive unit test charge and release it near a large distriibution of positive charge, that test charge has a potential energy that will be converted to kinetic energy as the repulsive force from the positive charge distribution drives it out. The kinetic energy it finally acquires is = its original potential energy and that potential energy divided by the test charge is called its PE per unit charge, or electric potential.

I wanna ask just to clarify, is coulomb a charge?

You nailed it .

starting from V = U/q how do i derive the formula V = k_e * (q/r)

best explanation .. thnx ...

thank u so much

hello,what you use the soft teacher?

Thx a bunch dude helped alot

This topic used to be tough but not now

Great video!

may i ask about the potential energy calculated using qv is relative to what point?

Helpful

can anyone please tell my why the v values will be big if they are near to the charge?? and why its value is less if it is away from charge??

It was this simple... why did I attend a 1 hour lecture to gain 0 knowledge when I could have just watched this 11 minute video and actually learn the topic...

Electric Potential of a charge Q, V=k*Q/r Units: [J/C] - Can be positive or negative depending on charge. - Electric Potential Energy = V*q = k*Q*q/r ; Units: [J] (or electric potential energy of a body of charge q placed at point in electric field of charge Q at distance r, will be: KQq/r ) (Def. Electric potential energy of a body at a point in an electric field of another body is defined as the amount of work done in bringing the given body from infinity to that point without acceleration.) Gravitational Potential of a mass M, U=GM/r Units: [J/Kg] - Always negative. - Gravitational Potential Energy = U*m = G*M*m/r (or gravitational potential energy of a body of mass m placed at point in gravitational field of mass M at distance r, will be: GMm/r ) (Def. Gravitational potential energy of a body at a point in a gravitational field of another body is defined as the amount of work done in bringing the given body from infinity to that point without acceleration.)

He cleared potential different topic in 10seconds

V=Fs cos theta /colulumb hence potential difference should be more with more displacement but u say potential should be more close to charge how...???

You're the best. I love u