Resistivity and conductivity | Circuits | Physics | Khan Academy

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  • Опубликовано: 16 ноя 2024

Комментарии • 119

  • @audreyandremington5265
    @audreyandremington5265 4 года назад +134

    Mike will be forever remembered as one of the greatest formula memorizers in the history of science class. His name will be preserved in the great records of human history as being included in this khan academy video.

    • @hageraliart
      @hageraliart 4 года назад +2

      Lol

    • @audreyandremington5265
      @audreyandremington5265 4 года назад +2

      @@hageraliart awe I'm glad you liked my joke!

    • @asissingh1823
      @asissingh1823 3 года назад +20

      @@audreyandremington5265 Mike is not a joke. You will now be reported to King Mike. Mike is inevitable.

    • @audreyandremington5265
      @audreyandremington5265 3 года назад +18

      @@asissingh1823 Please don't! I was young and naïve, I didn't know what I was doing!

    • @honeyz6386
      @honeyz6386 2 года назад +5

      @@audreyandremington5265 😂

  • @mageshwaridr.1927
    @mageshwaridr.1927 3 года назад +9

    Sir hats off to u...I was beating my head of not understand some physics concepts then God had gifted me ur videos....itz just osm... Thank a lot...I really mean it

  • @radiamoon2395
    @radiamoon2395 4 года назад +12

    thank you so much sir that really help. this video is from 2014 and today i'm watching it in 2019, thank you for posting this video.

    • @ECSowmyaM
      @ECSowmyaM 3 года назад +1

      And im watching it on the second wave of covid in India (2 June,2021)

  • @okay77561
    @okay77561 2 месяца назад +2

    thank you mike thats actually so helpful

  • @starbai410
    @starbai410 9 лет назад +36

    Excellent teacher!

    • @karmurmeraman3443
      @karmurmeraman3443 5 лет назад

      touge410 _ ruclips.net/video/y110pCHxAic/видео.html

    • @karmurmeraman3443
      @karmurmeraman3443 5 лет назад

      Hallo friends
      Plz subscribe my youtube channel for various electrical concepts and objective ques.
      Which are usefull to you for your any electrical exam and study purpose
      Thank you

  • @priscillalk5324
    @priscillalk5324 4 года назад +9

    best physics tutor
    thank you for making physics easy to understand 😁🙏

  • @sanjanavenkatesh9044
    @sanjanavenkatesh9044 4 года назад +7

    omg! I can't express to tell you how much I want to thank you. This video really helped me out

  • @luandanuredini6168
    @luandanuredini6168 3 года назад +8

    khan; how do I give the an advice indirectly hmm?
    also khan: oh yeah lets make an imaginary student and name him the most basic name ever :D that'll work

  • @prithak3263
    @prithak3263 8 лет назад +19

    hahaha good way to remember the formula of resistance. (REPLAY)
    i appreciate it...

    • @karmurmeraman3443
      @karmurmeraman3443 5 лет назад

      Hallo friends
      Plz subscribe my youtube channel for various electrical concepts and objective ques.
      Which are usefull to you for your any electrical exam and study purpose
      Thank you

  • @ultimatelocal
    @ultimatelocal 6 лет назад +4

    thank you mike

  • @subhashmodak7890
    @subhashmodak7890 7 лет назад +8

    Nice Formula to remember.

  • @joshpyburn
    @joshpyburn 6 лет назад +2

    My mnemonic for this is Rick Moranis playing the role of a Canadian general named Pouillet leading a feeble resistance and timidly issuing the demand "Role over, eh." Rho * L over A.

  • @Tee.NZ.07
    @Tee.NZ.07 9 лет назад +49

    not a subject you would normally find under medicine.

    • @raquelborn
      @raquelborn 7 лет назад +10

      Applies to medical engineering. Need electricity to power implants.

    • @jivra
      @jivra 7 лет назад +14

      MCAT tests knowledge of physics

    • @karmurmeraman3443
      @karmurmeraman3443 5 лет назад

      ruclips.net/video/y110pCHxAic/видео.html

    • @karmurmeraman3443
      @karmurmeraman3443 5 лет назад

      Hallo friends
      Plz subscribe my youtube channel for various electrical concepts and objective ques.
      Which are usefull to you for your any electrical exam and study purpose
      Thank you

    • @youngjunpark8412
      @youngjunpark8412 4 года назад +2

      This concept is applied to understand ion channels and some ion channels are targets of medicine.

  • @Jamesyoung450
    @Jamesyoung450 10 лет назад +5

    How isn't your channel more popular?

  • @danilkinsss
    @danilkinsss 2 года назад

    God bless MIke!!

  • @bibijohora2061
    @bibijohora2061 2 года назад

    My confusion has cleared... Thank a lot sir...

  • @yourfuturedocburenbeiya
    @yourfuturedocburenbeiya 3 года назад

    I like the "replay"; thank you so much!!

  • @kasperbaun
    @kasperbaun 6 лет назад +2

    Really awsome video.. thanks alot !

  • @siva7930
    @siva7930 4 года назад +1

    very good explanation.thank u 😍

  • @ebhojayejuliet9728
    @ebhojayejuliet9728 Год назад

    You're really good but organic chemistry tutor is goated 🐐

  • @saeedalminji4821
    @saeedalminji4821 4 года назад +1

    thank you so much i passed grade 12 becuase of u

  • @ShrirangChandankhede
    @ShrirangChandankhede 3 года назад

    best lecture on youtube

  • @samriddhi0906
    @samriddhi0906 Месяц назад

    thankyou!❤

  • @pridhisoni3789
    @pridhisoni3789 2 года назад

    This video was just on fleek✨

  • @therock2730
    @therock2730 7 лет назад +2

    marvelous teacher thank you soooooo much finally my doubt cleared keep uploading such a awesome videos

    • @karmurmeraman3443
      @karmurmeraman3443 5 лет назад

      the rock
      Hallo friends
      Plz subscribe my youtube channel for various electrical concepts and objective ques.
      Which are usefull to you for your any electrical exam and study purpose
      Thank you

    • @karmurmeraman3443
      @karmurmeraman3443 5 лет назад

      ruclips.net/video/y110pCHxAic/видео.html

  • @vince6829
    @vince6829 Год назад

    Nice explanation. Thanks for sharing.

  • @Adihaivai
    @Adihaivai 7 месяцев назад

    LORD MIKE !!!!!!!!!

  • @ChinitheLovebird
    @ChinitheLovebird Год назад

    Thankyousomuch sir!

  • @oscarjrdepamaylo3673
    @oscarjrdepamaylo3673 3 года назад

    REPLAY hahaha. I won;'t miss it anymore

  • @meganbermudez299
    @meganbermudez299 4 года назад +1

    we all gotta clap for Mike

  • @howcreated_ideas
    @howcreated_ideas 3 года назад

    Thanks for sharing..

  • @soniaadetu4560
    @soniaadetu4560 4 года назад

    Thanks so so much

  • @SpeakerWiggin49
    @SpeakerWiggin49 2 года назад

    Great video. I just wish we had a different way of describing current pass-through to beginners other than "flow." Electrical current doesn't "flow" through wires like water in a pipe, if anything you can say that it "flows" _into_ the wire when voltage is applied. After the equation for energy and resistance is understood, we should stop discussing conductivity and resistivity with the word "flow" in reference to current attached to parts on the circuit.

  • @ritvikasingh9273
    @ritvikasingh9273 4 года назад

    Nice explanation

  • @basz7802
    @basz7802 5 лет назад

    this helped so much cheers boss

  • @studybuddy5066
    @studybuddy5066 4 года назад

    Thank you. It really helped.

  • @steffliot3788
    @steffliot3788 5 лет назад

    Thanks a lot. This video is so so so helpful. Thankyou.

  • @Randomperson-tu5we
    @Randomperson-tu5we 2 года назад

    I'm only here to understand this more so I can explain it to my uncle because he doesn't understand maths or physica as well as I do 😭
    I never thought I would be doing something like this on a weekend at the age of 14

    • @ashrayiyer1166
      @ashrayiyer1166 2 года назад

      why da heck ur uncle wanna learn physics

  • @PressPlayObey
    @PressPlayObey 10 лет назад

    My favorite channel :)

  • @briandahl1659
    @briandahl1659 6 лет назад +1

    1:56 - You state that changing the shape of the resistor will change its resistance. This is a common misconception. If all other factors are held constant the shape does not affect the resistance. For instance a square wire would have the same resistance as a round wire if they were identical in all other regards. This misconception comes from the thought that if you change the shape you necessarily would change the cross-section (size) of the conductor. This isn't necessarily true as you could have a square wire with the same cross section as the round wire.

  • @dawood.jarral
    @dawood.jarral 8 лет назад

    Thankyousomuch!!!
    it cleared so many questions..

    • @dawood.jarral
      @dawood.jarral 8 лет назад

      basically something good at conducting is bad at resistivity and vise versa.. so simple to remember..

    • @karmurmeraman3443
      @karmurmeraman3443 5 лет назад

      Hallo friends
      Plz subscribe my youtube channel for various electrical concepts and objective ques.
      Which are usefull to you for your any electrical exam and study purpose
      Thank you

  • @Dev-dn4uu
    @Dev-dn4uu 4 года назад

    I love you mike -Yoel Romero

  • @Scientificeducation785
    @Scientificeducation785 7 лет назад

    nice explanation..

  • @nnekaokehieson8505
    @nnekaokehieson8505 4 года назад

    What did you do with the pie sign when calculating the resistance

  • @Gjcbox_Obob
    @Gjcbox_Obob 11 месяцев назад +2

    Hey how did you do the calculation at the end? This math is so f*cking complicated for me! Pls explain to me if anyone is reading this comment.. 🙏

    • @WalterWipe
      @WalterWipe 7 месяцев назад +1

      Basically, the equation gets rewritten with the letters "P", "L", and "A" getting replaced with what they represent in the conducter. The "P" represents the resistivity of the metal. As stated in the question, the metal has a resistivity of (i dont feel like rewriting that). Because resistivity is measured in Ohms, the symbol is written next to it. Then, that amount is multiplied by the total length of the resistor. Next, you have "L"/"A". L, which represents the length of the wire, is replaced with the total length of the wire (12m). A, the area of the base of the cylinder, is replaced with the equation for finding the area of a circle (pi * r²). You are given the diameter (0.01m), so you convert it to a radius (divide by 2), getting 0.005m as a result. The final equation for "A" is pi * 0.005m². After that, you put in your calculator the full equation of (1.68 * 10^-8 Omhs * 12m) * (12 / pi *0.005m²). I hope this helped with whatever part you didnt understand. I'm only in 7th grade now when I'm explaining this and I dont know too much, but I can still try and help you with any other questions you still might have.

    • @WalterWipe
      @WalterWipe 7 месяцев назад +1

      Uhh that actually didnt fully work so idk how he got that answer. I dont have a calculator for this stuff.

  • @jagadeesansri6711
    @jagadeesansri6711 4 года назад

    Thanks u

  • @serene9532
    @serene9532 6 лет назад +5

    ...is it really pronounced "REE-zistivity"?! Gosh I've always said it normally like "resist-ivity"

  • @mritunjay2624
    @mritunjay2624 7 лет назад

    Thanks

  • @sohamjain6206
    @sohamjain6206 4 года назад +1

    How can you quantitatively derive to the resistivity if not given? (plz respond if you know)

  • @thoughtsespresso6348
    @thoughtsespresso6348 7 лет назад +1

    i lovve youuuu...thanks for clearing my concepts !!!! *-:

  • @ray8417
    @ray8417 5 лет назад

    I remember "R*A=ρ*l", so rapol or rapl

  • @pierrzmalaka
    @pierrzmalaka 9 лет назад

    Would you know how to calculate the resistance of a distilled water mixed with salt? How can I reach a certain resistance in a solution of salt and distilled water?

  • @thatomofolo452
    @thatomofolo452 9 месяцев назад

    R(x)=x/+x

  • @freshsuzuki4014
    @freshsuzuki4014 8 лет назад

    amazing

  • @hankmoody9023
    @hankmoody9023 6 лет назад

    how come the fluid has a slower velocity on the right hand side as opposed to the left? Is it only due to friction or are there some other underlying reasons?

  • @dynamicdiggingduo
    @dynamicdiggingduo Месяц назад +1

    watching it after 10years in 2024😂😂🤣🤣

  • @okay77561
    @okay77561 2 месяца назад

    7:10 erm what the sigma

  • @changingspiritually9540
    @changingspiritually9540 4 года назад

    Thank you but next time make sure there is no black and white as people can be dyslexic. Make sure the writing is in a color friendly for dyslexia.

  • @chetalibhawsar4326
    @chetalibhawsar4326 6 лет назад

    you write (0.005)^2 square as ( 0.0026) instead of writing (0.0025)

    • @bimarshadhikari5662
      @bimarshadhikari5662 5 лет назад

      Well, that result might be something that's a calculation of the whole equation.

  • @bdasaw
    @bdasaw 6 лет назад

    damnn Mike a real nigga

  • @nigeltims8781
    @nigeltims8781 7 лет назад +1

    how does an ohm meter measure resistivity? i cant understand this logically

    • @pragyakhanna3331
      @pragyakhanna3331 7 лет назад +1

      According to his explanation, ρ= R x A/L
      So by just placing the units- The unit of Resistance is ohm
      The unit of area of cross section A is(metre)^2
      The unit of length is metre
      Which gives,
      ρ= ohm x (metre)^2 /metre
      ρ= ohm-metre ( Ω metre)

    • @adityaprakash8393
      @adityaprakash8393 7 лет назад

      logically understanding units in physics is pointless for many of them.think about momentum 'MV' ,MAKES sense? like simple standard 1multiplication is repeated addition,no!
      units are mathematical artefacts to maintain the ratio dependence

  • @saniabatool6000
    @saniabatool6000 6 лет назад

    Why resistivity is not zero at 0 °C ??

  • @RawDoggin_78
    @RawDoggin_78 2 года назад +1

    me, a non native who didn't know the difference between radius and diameter, looking at the last question:
    *thanos voice*
    reality is often disappointing

  • @okay77561
    @okay77561 2 месяца назад

    why does he say resistivity like that

  • @P.vishnudutta
    @P.vishnudutta Год назад

    Repla

  • @kaifansari7482
    @kaifansari7482 4 года назад

    Too hard made by you

  • @kagogoveya6213
    @kagogoveya6213 9 лет назад

    V=IR is not ohm's law!!

    • @Cat-qn7pm
      @Cat-qn7pm 9 лет назад +1

      Kago Goveya en.wikipedia.org/wiki/Ohm%27s_law

    • @psaven
      @psaven 9 лет назад +1

      +Cat Anderson In some places U is used for the voltage i.e. U=RI

    • @amarpreetsingh6394
      @amarpreetsingh6394 8 лет назад +1

      +Kago Goveya..... it is the law of ohm where R is the constant of proportionality

  • @Japanese_one_Tokyo
    @Japanese_one_Tokyo 5 лет назад

    geeks

  • @JP-xm3qf
    @JP-xm3qf 6 лет назад +2

    What happened so Sal? I want to hear his voice as usual, this person speaks too fast and doesn’t explain as well, should be re-done by Sal!

    • @karmurmeraman3443
      @karmurmeraman3443 5 лет назад

      Julio Padilla
      Hallo friends
      Plz subscribe my youtube channel for various electrical concepts and objective ques.
      Which are usefull to you for your any electrical exam and study purpose
      Thank you

  • @dalenassar9152
    @dalenassar9152 5 лет назад

    Your REPLAY trick is ok but it is NOT the way to teach, in a technical school, the PHYSICAL MEANING of resistivity (rho). The students should first be taught to consider a length of wire (as solid cylinder) in which the electrons flow. When you think of a cylinder, what are it's two main parameters? (I asked several people about this and got the SAME answers: HEIGHT,L, & RADIUS, r). Common sense tells us that the longer L is, the higher the resistance, and the larger the cross sectional area (proportional to r^r) the less the resistance. So, resistance is directly proportional to L and inversely proportional to the cross sectional area, A. So R~L/A. And the proportionally constant is rho. So, forming the equation, R=(rho)*L/A.

    • @karmurmeraman3443
      @karmurmeraman3443 5 лет назад

      dale nassar
      Hallo friends
      Plz subscribe my youtube channel for various electrical concepts and objective ques.
      Which are usefull to you for your any electrical exam and study purpose
      Thank you

  • @ariestheram9326
    @ariestheram9326 4 года назад

    thanks mike

  • @smoke-tt1sr
    @smoke-tt1sr 2 года назад

    Thank you!

  • @hypencomics6379
    @hypencomics6379 5 лет назад

    Sir you are doing great job