Electric power | Circuits | Physics | Khan Academy

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  • Опубликовано: 28 июл 2016
  • In this video David derives the formula to find the power used by a resistor. Created by David SantoPietro.
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Комментарии • 53

  • @miragharzayev8002
    @miragharzayev8002 3 года назад +19

    I am a student in a country maybe you have never heard its name or gonna hear it. But I get more benefits from your videos than my university class. I want to thanks google and khan academy for this great opportunity that they are giving us. You are really trying to make the world a better place.

    • @popeye9872
      @popeye9872 2 года назад +2

      What's your country name?

    • @hariharasudhan149
      @hariharasudhan149 Год назад +2

      Credits to Khan academy
      For helping me with my 12th boards

  • @reezis1619
    @reezis1619 7 лет назад +31

    Your channel deserves way more recognition, amazing profound intuitive explanation. Great job!

  • @floundericiouswa5694
    @floundericiouswa5694 5 лет назад +4

    Nice 101 coverage in 10 minutes
    ...and you showed your work and all the ways you can rearrange/restate the basic definition.

  • @RedBlueLabs
    @RedBlueLabs 6 лет назад +6

    This video is awesome! It is a great teaching resource. Well Done!

  • @marwanmohamed9111
    @marwanmohamed9111 4 года назад +1

    simply amazing, ty.

  • @dvirbensimhon3355
    @dvirbensimhon3355 5 лет назад

    amazing! thank you!

  • @terrancezheng7972
    @terrancezheng7972 4 года назад +4

    I screamed when I realized that power is equal to the current x voltage of the resistor.! Yr10 doing engineering and coding

  • @victoriacorcimaru1731
    @victoriacorcimaru1731 2 года назад

    You are awesome! thanks for making this so easy

  •  5 лет назад +2

    thank you so much,sir

  • @aliyantahir3696
    @aliyantahir3696 5 лет назад +1

    thankx david

  • @sharifali9673
    @sharifali9673 4 года назад

    awesome as always

  • @parulaggarwal9405
    @parulaggarwal9405 6 лет назад

    Thnk u

  • @c260sadiaafrin2
    @c260sadiaafrin2 3 года назад

    Thank u so much sir 💙

  • @av6966
    @av6966 6 лет назад +2

    I used to tell my teacher that Khan videos werent great, but clearly I was wrong! V.Nice explanation for the power equation!!

    • @Anonymous-if9mp
      @Anonymous-if9mp 5 лет назад +8

      What makes u feel like that in the first place?

  • @ftAlpha-yz1zs
    @ftAlpha-yz1zs 4 года назад

    Thanks sir

  • @mungkornchotinawanon7604
    @mungkornchotinawanon7604 2 года назад +1

    I want to have Thai subtitles too.

  • @maheshbansiwal7836
    @maheshbansiwal7836 3 года назад

    Nice video world best you tube channel in teaching is khan academy 👍👍👍

  • @andrcarb
    @andrcarb 5 месяцев назад

    Man you are good

  • @c260sadiaafrin2
    @c260sadiaafrin2 3 года назад

    Blessed 😇😇😇😇😇😇😇

  • @moazelsawaf2000
    @moazelsawaf2000 4 года назад

    Thanks

  • @anastasiaanautodidact9856
    @anastasiaanautodidact9856 3 года назад +1

    How is this so underrated

    • @schmetterling4477
      @schmetterling4477 2 года назад

      Why is it underrated? It's exactly the same material that you can find in any high school physics textbook about electricity.

  • @a1ex246
    @a1ex246 3 месяца назад

    found this on fctc study playlist. So far everything has been good. Didn't understand this video at all. All the variables threw me off

  • @sohinipaul2429
    @sohinipaul2429 7 лет назад

    what triggers the K.E to remain constant while flowing through the wire. And what's the origin of this K.E ??

    • @sphyr4973
      @sphyr4973 5 лет назад +2

      Late response, but the reason why speed is constant is that it's a closed loop. So a change in velocity in point A would result in
      1) a "clog" of elec charges forming (we assume it never happens because like charges keep themselves as far apart as possible)
      2)all of the flow speeds up (that can't happen because it would break the conservation of energy)
      So all extra KE is converted in vibration, aka heat

    • @audreyandremington5265
      @audreyandremington5265 4 года назад

      ​@@sphyr4973 Imagine a closed circuit with no resistor, and not only that, but also minimal resistance throughout the circuit. Wouldn't the electric potential at the negative end of the battery be less than that at the positive end of the battery, since a positive test charge would be attracted to the negative end and repelled from the positive end? If there is a difference in potential energy across the circuit, then where is the potential energy going? Since this hypothetical circuit has practically no resistance, the PE can't be turning into heat.

    • @Estromictylingene
      @Estromictylingene 2 года назад

      1)resistance is proportional to the length of wires that connect the circuit and inversely proportional to the diameter of wires,2)high temperatures mean high resistance and also
      3)the element the wire made of makes resistance varies.Even if you say there is no resistor,the electrons that flow in wires attack the atoms causing them to shake more and produce heat and we measure heat energy in joules so power(watt)= j/s thus there is a voltage difference between any two points in a circuit regardless of having a resistor or having less resistance but its still having resistance.

    • @Estromictylingene
      @Estromictylingene 2 года назад

      So yeah that's why if there is seemingly no resistance,there is. and that makes the wires hot or consumes power(In a closed circuit)

  • @tunnelvision7906
    @tunnelvision7906 4 года назад

    Why is the voltage across the resistor the same as the change of voltage? If you apply 6 volts how is that the change between the resistor?

    • @schmetterling4477
      @schmetterling4477 2 года назад +1

      Voltage is the "change" in potential. The potential can be anything you like. It doesn't matter.

  • @av6966
    @av6966 6 лет назад

    A thousandth of people have an opinion about what they like apparently!

  • @hajrahomar3020
    @hajrahomar3020 3 года назад

    Idg how they come out from the resistor with the same kinetic energy they started with?????//

    • @schmetterling4477
      @schmetterling4477 2 года назад +1

      Kinetic energy does not play any relevant role here. This is all about potential energy.

  • @briankirkland8870
    @briankirkland8870 7 лет назад

    i thought protons dont move

    • @RedBlueLabs
      @RedBlueLabs 6 лет назад +6

      they don't, he explained why

    • @monke12354
      @monke12354 6 лет назад +5

      He explained why actually multiple times did you watch the video lol

  • @vinodhi576
    @vinodhi576 5 лет назад

    Electrons produce electric current. Not positive charges

  • @Mohamed_Karam551
    @Mohamed_Karam551 4 года назад +1

    I want Arabic caption 😢😢

  • @JP-xm3qf
    @JP-xm3qf 5 лет назад +2

    Dude, learn from Sal and speak slower and give better explanations; as soon as Sal stopped doing these videos, the quality lowered.

    • @ayaandanish
      @ayaandanish 5 лет назад

      Why DID Sal stop?

    • @zaed7419
      @zaed7419 4 года назад

      Idk I like this guy

    • @water6133
      @water6133 2 года назад

      I think this guy was ok too ,I like him

  • @mohamedgamal7600
    @mohamedgamal7600 6 лет назад

    extremely bad and boring explanation keep repeating and repeating same words