Resistors in series | Circuits | Physics | Khan Academy

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Resistors that come one after another. Created by Sal Khan.
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Опубликовано:

21 сен 2024

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Комментарии : 278

@Kai-Xi 10 лет назад

0:48 "If there is any such thing as reality" XD

@panchvangapandu5349 9 лет назад

Derpy Hooves lol, Khan Academy getting philosophical...

@MrSocialish 7 лет назад

LMAO i just came from the khan academy website to the RU-vid video just to make the comment you just said! Khan is more than a person. He is an omniscient force.

@bryllethe13 5 лет назад

hahahahahaa

@hassanhamze_14 3 года назад

Are you guys alive in 2021

@AnaOhKay 4 месяца назад

@@hassanhamze_14 are *you* alive in 2024?

@khanacademy 15 лет назад

Real-world wires have resistance, but in the diagrams, we assume that the non-resistor part of the circuits have no resistance (or that it has all been added to the "resistance" in the diagram)

@thanaa6401 16 дней назад

If there was perfect conductor wire and no resistors at all. Does that mean that the voltage between any 2 points is equal to 0? But that makes no sense since each battery has some Nonzero voltage

@vishnureddy3977 9 лет назад

"My wife will probably mind that I didn't answer" LOL

@phalafau1258 7 лет назад

Marriage standards

@midnightsilverpuppy 7 лет назад

"For fun let's put in a third resistor" Me: "whoa! U wild"

@biotch77 11 лет назад

"but what we know in reality what is happening, if there is such a thing as reality..." sal, you're awesome.

@MrManwookie 10 лет назад

"If there is any such thing as reality" Sal's having another existential crisis :P

@lucasgdrezes 8 лет назад

I don't wanna be an electrical engineer, I just wanna got some questions right on the test I'm having tomorrow.

@DonJuliusss 5 лет назад

@gomugomutree6075 3 года назад

i hope you did well on your test

@hey9530 3 года назад

Five YEars Later -> How'd u do on the test?

@lucasgdrezes 2 года назад

@@hey9530 Well, I graduated high school without any problems. The video was helpful!

@lucasgdrezes 2 года назад

@just some guy tired of life Yessir.

@cierrapresson4163 8 лет назад

I love that Sal managed to slip in a little philosophy while he was at it.

@aaronsilver-pell411 4 года назад

you can't really do physics well without philosophy

@genchani8537 11 лет назад

OMG this is so simple. When my professor explained this part it sounded so damn hard. I wish you were my professor :) Btw, thanks a lot for these videos.

@GreatMasterOogway 10 лет назад

we all wish he were our professor :'(

@ernestosaboia 6 лет назад

4:58 Hey Sal, thanks for all your teaching and sharing, so here is my small contribution: Electricity in a wire moves at 2/3 of speed of light, electrons move very slow :)

@csdvrrecordingstudios7272 3 года назад

U learn something new every day 😊😊

@Becca11Dance 12 лет назад

His voice is so relaxing :)

@Sheikisspear 4 года назад

Hahahaha

@skarpengland 8 лет назад

So, i used Khan academy all last year when i did my basic introductory course in medicine. now, i am doing physics and chemistry to hopefully enter medical school... and didnt you know, Khan can help you in physics as well! THANKS!

@fadyfarouk8635 8 лет назад

good luck!

@skarpengland 8 лет назад

i got accepted! i also got exactly the stuff in this video, in my physics exam. talk about coincidence

@fadyfarouk8635 8 лет назад

***** wow good job, I hope I get accepted too. Have a great college period!

@kschwab14 13 лет назад

"It's my wife, she'll probably mind that i didn't answer but anyway...." haha love the dedication

@seanki98 8 лет назад

0:48 deep

@user_z11 4 года назад

Yeah

@Hiandbye95 12 лет назад

I think the amazing thing about your videos is that I understand everything you explain. This is something I rarely experience in school. xD

@vomitingteddy 10 лет назад

should have answered the phone man

@Daski69 12 лет назад

I'd like to initiate this comment with a huge THANKS to you Mr Khan, you're a genius! Second, I'd like to contribute with a personal idea, to people who have a hard time with understanding some basics when it comes to circuits, like I used to have. Why is it so that the voltage over the "more powerful" resistor is higher than the other. Well, voltage is defined as energy/charge. It requires more energy to get pass the big resistor than the small, simple. Over and out.

@mitch3850 12 лет назад

Sal is the man. I attend university in Victoria, Australia, and one of my classes is Electrical Systems. The lecturers are very smart but they forget that many students haven't dealt with the basic concepts of electrical functions, and tend to skip over them. I'm 12 weeks in and about to sit my exam, and before seeing these videos I was really worried. But SAL MAKES IT SO F***ING CLEAR. If I get a pass, it's due to Sal and Khan. Thanks man!

@greenscreenasshole Год назад

Did you pass though

@mitch3850 Год назад

@@greenscreenasshole I actually did!

@tonynasaofficial 6 месяцев назад

@@mitch3850 congrats!

@aumgandhewar3114 2 года назад

I love how y'all maintain retention by being friendly and sometimes amusing

@poonamjoshi1101 4 года назад

Man! Whoa Sal! 'If there is anything such as reality'-words of a legend (going through an existential crisis)

@Ray-tf2ps 5 лет назад

"when resistors in series we just add them up" YOU COULD'VE SAID THAT AT THE BEGINNING. But the explanation did help fix my curiosity

@reezis1619 7 лет назад

After watching 6 minutes of the video I just wanted to say that you are AMAZING at explaining things. You make everything so easy to comprehend

@jaydaappleton6463 3 года назад

He is such a good teacher. I literally came here knowing nothing about circuits, and after watching this video I somehow am completely ready to complete my lab work. Now the work suddenly seems so easy.

@gh-rb7bb 8 лет назад

thanks man I wish u were my physics teacher

@TimWhiteNC 11 лет назад

Sal is the Bob Ross of Science.

@tristanisgangsa 12 лет назад

THANK YOU FOR THE CLOSED CAPTIONS! :D It's great for hearing loss and to check if you miss something! :D

@danoconnor4452 5 лет назад

I know this is 12 years old so you’re probably not going to read this, but what helps me understand that the current is constant is to think of electrons as cars and the circuit as the road. At each “resistor” in the road, the speed limit decreases by a certain amount. So the bottleneck of electrons is analogous to bad traffic. The main difference is that electrons don’t “travel” along the wire like a car travels on the road; meaning that the instant you turn on the circuit, the current is constant. You don’t have to wait for the electrons to “travel” to each resistor, creating a bottleneck and then having it slow all the previous electrons down (which is what happens in traffic).

@hiyabalemayehu3443 4 года назад

I know you guys think this guy is the best teacher but what I'm about to say is different THIS GUY JUST EXPLAINED THIS TO ME PERFECTLY, SOMETHING MY TEACHER COULDNT DO FOR A MONTH.

@madhusai220 6 лет назад

0:48, from that moment to this moment, i'm living in existential depression...

@grigoriyefimovichrasputin7897 5 лет назад

I think its cool that really nothings real But dont worry bout it STRAW BERRY FEILDS FOREVER

@kabascoolr 11 лет назад

Lol I didn't know that he made videos on circuits. These, especially Kirchhoff's Laws really kicked my behind last semester. It's mostly because our professor was under the assumption that we knew circuits well before entering his class. I did but I'd forgotten most of the things.

@brianhartmann5972 10 лет назад

Kahn academy is very helpful, in fact I watched this video to clarify some my knowledge on circuits because my physics teacher was unclear. However, in a battery, the electrons do in fact flow from the end known as "positive". This may be confusing at first but the reason that it is denoted this way is because that is the side with the higher electric potential energy (the side with all of the electrons, so it actually does flow from the positive end to the negative end). Other than that, this was a great video. I just wanted to clarify

@NoahA211 12 лет назад

I would honestly rather listen to these videos and just go to class on test days than having to sit through mundane class after mundane class...learning nothing. You are a life saver Khan!

@Mrs_Potential 5 лет назад

thank you very much. i totally have a different view on physics. its actually easier and more sensible than i thought. thank you

@mitch3850 12 лет назад

Sal is the guy talking, Khan is the academy he represents.

@warrencurrymetal 9 лет назад

18 people were amish

@dhurbarajpuree2992 2 года назад

This guy is so f*king genius. Love to learn from Khan academy. They are the gems.

@NitishChauhan1 11 лет назад

"if there's any such thing as reality" i've never seen a prof. get more specific when setting a premise.

@ScottLahteine 10 лет назад

I'm just starting on this path with electronics, so naturally I count on Khan to set me straight. But this is a little confusing as laid out. First, sure, label the battery output terminal + (as in, adding electrons here) but perhaps denote that the + terminal is negatively charged (neg.) because electrons are negatively charged. And just don't label the other terminal. Second, as I understand it resistors convert electrons into heat and radiate, so electrons are actually being spent by the circuit, and that is why the current drops. Correct me if I misunderstand this. Also, correct me if I'm wrong that: The potential difference (voltage) is the same across the entire series circuit, only the load is dropping, and smart DC power supplies will only feed the required amperes (for the given voltage) to power the circuit.

@Tuanski 9 лет назад

I have a new religion called "Salmankhanism"

@hageraliart 3 года назад

Could someone please tell me what exactly causes the potential drop when charges across a resistors?

@rtsjoe 14 лет назад

I love it how he pauses to think how to put things in layman's terms.

@aniquanausheen7798 8 лет назад

i like this khan academy.. its awesome.

@sharkbaitoohhaha2341 12 лет назад

If Sal ever has kids, they will be all-knowing!!

@kelvinmann7993 3 года назад

I'm honestly just learning this so I can make circuit boards for music boxes. My brain is gonna hate me

@sethboston6356 7 лет назад

You really have a way with teaching, as I am sure you have been told many times before. Thank you

@abishekdahal403 12 лет назад

khan your voice is also a + point for your explanation

@jorgediaz549 11 лет назад

I love this guy! circuits + comedy = priceless

@tonix1993 12 лет назад

Funny thing about the video is that in part 5:20 you say that electrons cant slow down just before the pass through the Ressistor.Thats not very right Well physics is so harmony that can allow that to happen xD think about it...if they slow down they compressed so they become a big minus charge in that area of the Circuit. Result? they slow down the upcoming electrons and in same time they push away on the other diraction the other electrons!!! Love physics ^^

@dinoLomedico 13 лет назад

This gentleman is an excellent teacher !!!

@neurel111 13 лет назад

Electrons don't move across the circuit anywhere close to the speed of light. Their motion propagates at the speed of light. So when the first electron moves it takes the last electron to move as much time as it would take light from the first electron to reach the last electron across the circuit.

@TheSantanu99 11 лет назад

"if there is any such thing as reality" 0:46 - Classic Sal

@htmlfreak 15 лет назад

I believe total resistance in circuits are the following: In parallel circuits, the 1/R1 + 1/R2 = 1/RT (RT = Resistance Total) In series circuits, the total resistance is just the sum of all the individual resistors: thus R1 + R2 = RT Hope that helped.

@WalkAbout28 7 лет назад

Sal has taught me math through calculus, organic chemistry, and now physics

@chainheart3 12 лет назад

tanks! this video is awesome!

@poonamjoshi1101 4 года назад

I don't want to become an electrical engineer, I just want to give my best in NSO exam

@Physicsandmaths 15 лет назад

Yes, if the material is above its critical temperature it's not a superconductor.

@DrLasker1 13 лет назад

thanks again sal! you mentioned a lot of small but important details which my physics teacher didn't mention (or perhaps I missed them because I was sleeping =), which really helped me understand this better! thanks!

@kamikrazi123 13 лет назад

How is this guy so damn smart??

@nileshpatil8665 4 года назад

I didn't understand why the current is the same and why the total voltage is the sum of all the voltage drops. I don't like expiremental proofs that is why I am so confused. Pls answer

@Hax04r 10 лет назад

@jaskaransingh because the battery is separated in a cathode(negative) and an anode(positive). There is a material between the two that has a higher resistance than the battery's voltage(basically the electrons are too weak to move through it). So the electrons can feel the force between the positive and negative terminals but they don't have the power to move. BUT when someone puts a wire between the two terminals(anode and cathode) the electrons can now move

@devigopalakrishnan2909 5 лет назад

This video is great!!!

@WalterWipe 5 месяцев назад

10:02 we litterally both thought of the same numbers lol

@bladervinay 12 лет назад

Ha ha 'Oh oh its my wife she will mind if i dont answer but anyway' Ohhhh you are brilliant Sal!!! Funny and brilliant

@Becca11Dance 12 лет назад

Is there any such thing as reality? That, my friend is a very good question.

@BaronMorte 14 лет назад

Sal,you are the man. Thank you.

@GENEis1Wascally 14 лет назад

I liked the video. He is a very good instructor!

@Fmiguelify 12 лет назад

Thankj you, this video is really good, i undestand more about the series Circut now, and about the Volt Drops on the eacht resisters.

@comedian619 11 лет назад

Very Helpful.Thank you

@SaM0o0Na 10 лет назад

will after the first tow videos I felt more comfortable because I could understand something now. I will contenw watching them and I hope that I will get A on my upcoming MT.

@_underrated_dre_ 2 года назад

So will the total resistance or actually the way of funding the total resistance be the same for a parallel circuit?

@jaylonso6939 11 лет назад

You know a video is interesting when you dont look at the time once,thats what happens with all of khan's videos !

@actionjessie 13 лет назад

lol at "if there is such a thing as reality"..

@TareqKhan0 6 лет назад

A correction at 4:55. Electrons do not move at the speed of light through copper wire. Inside the wires, electron moves very, very slowly, almost as slowly as the minute hand on a clock. Electric current is like slowly flowing water inside a hose. Very slow, so perhaps a flow of syrup. Read more: amasci.com/miscon/speed.html

@dulanherath5927 3 года назад

Best explanation👍

@tadm123 13 лет назад

I have a question is the Current always constant everywhere on the circuit? or just in the cable not going through resistors?

@techmaster90 5 лет назад

This is great thank you!

@spilloholiker 13 лет назад

@69elchupacabra69 Electrons move very fast. But the reason the current moves so slow is that the way the current flows, is that one electron bumps into another. So imagine that in a tiny bit of wire there are 1000 electrons. The electron that comes into the wire bumps into the first one, that bumps into the second one, and it continues that way until it reaches electron number 1000. In all of that time it took these electron to bump into eachother, only 1 electron made it's way out of the wire.

@alissajeanfreau7741 6 лет назад

I'm confused on how in the beginning, he said that the voltage is the same no matter where you measure, from at the end there being a difference in voltage from the beginning of the resistor to the end

@atombarn223 3 года назад

So your voltage will be the same when you put your meter from the positive and negative of your power supply OR the start R1 to the end of R3. Not in between each resistor. The Current (I) will be the same in between each resistor. To get your voltage in between each resistor you'll just take the current total and multiply it by the value of the resistor. Hope I was clear enough and this helps.

@landenwolever1016 7 лет назад

is the voltage constant throughout the circuit or is there a different voltage at two given points around each resistor?

@nana_smallmango 4 года назад

I love Khan Academy

@Arthur85666 10 лет назад

electrons actually travel very slowly, but since a lot of electrons are moving throughout the wire the effect is very fast.

@Alapozo 8 лет назад

This was a very good video!!! Great explanations

@Marsc0met 13 лет назад

@xDivineForYou @69elchupacabra69 electrons do flow very slowly. "For a typical metal, n = 10^28 m^-3, if the current is I A in a wire of cross-sectional area 10^-6 m^2 (a typical wire), we find v = 6 * 10^04 ms^-1. This is quite a LOW SPEED. If we turn on teh switch for the lights (5 m away), we certainly do not wait 139 min for the lights to come on! This is because , when the switch is turned on, an electric field is established within the wire. This happens close to the speed of light."

@Physicsandmaths 15 лет назад

Hey Sal, You said no wires without resistivity exist. Well, superconductors don't have any! They have a resistance of absolute zero.

@SanFranLOVER1972 12 лет назад

I love you. Seriously. MUCHO LOVE FROM GEORGIA IS BEING SENT YOUR WAAAAAAAAAAAAY!

@KarishmaGReddy 16 лет назад

great video!! thanks so much

@knguyen542 8 лет назад

Would electrons not bunch up due to "like charges"? Thank you this video helped a lot.

@studyclub1664 5 лет назад

Excellent feaitu

@danielking7100 6 лет назад

this video changed my life

@sphericalcow4004 6 лет назад

Same bro

@danielking7100 6 лет назад

dude who are you?

@sphericalcow4004 6 лет назад

it's a me. mario

@mini-337 Год назад

Thank you sir

@EldonSchoop 13 лет назад

@xDivineForYou, Well you are correct that electrons flow faster than a few inches per hour (!), remember that electrons are pushing on other electrons in the cable, and the light would turn on almost instantly anyway. Think of it like a hose full of water that is just turned on. Of course the flow of the water isn't terribly fast, but the water that is currently in the hose is pushed out immediately, causing a seemingly instantaneous flow of water. Same deal with electrons. :)

@snowflowertea 6 лет назад

When Resistors Are In Series Just Add Them Up - Sal Khan 2008

@11031992em 13 лет назад

sir, do you have "wye, delta" circuit analysis examples?,

@Anintora 3 года назад

im convinced sal thinks we all live in a simulation

@natemullikin6248 4 года назад

Were they flowing before I observed them? Were they? were they.....

@vedatbajraktari5806 8 лет назад

Nice job. Really im a university student but there in class is so boring and rabish lecture. Thank u, we looking forward to see more videos.

@viktorgoa 14 лет назад

yes, they travel slowly. The reason why its fast, that its going in waves

@TheLexicanable 12 лет назад

If there is any such thing as a reality.

@진바라기-u7n 8 лет назад

i've learned that electron in a circuit cannot move at the rate of light. a lot of electrons in conductor just move at the same time when pushing the electric force. Im confused in that point.. i want to know the theory accurately