Rotational version of Newton's second law | Physics | Khan Academy

In this video David explains moment of inertia and the rotational version of Newton's second law and shows how to solve an example problem.
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Пікірлер: 32

  • @ptyptypty3
    @ptyptypty36 жыл бұрын

    this video is by far the best I've seen on this subject!!.. Thank YOU!!.. I wondered how the Radius, R, was used as R^2 in the I= mR^2.. and YOU showed me!!!.. Great video!!..

  • @ryanlang2921
    @ryanlang29215 жыл бұрын

    I have been stuck on physics for a week and this video made it just click. Thank you so much.

  • @looksintolasers
    @looksintolasers6 жыл бұрын

    This needs to be retagged! Searching for "Moment of inertia" and "rotational inertia" showed nothing! 70 views! That's criminal!

  • @looksintolasers

    @looksintolasers

    6 жыл бұрын

    Also, congrats on finding out how to be a physics teacher without the grading :D

  • @yw5617

    @yw5617

    6 жыл бұрын

    I'm going to show this to everyone I know, this needs attention

  • @AliVeli-gr4fb
    @AliVeli-gr4fb7 жыл бұрын

    thank you, nice explanation, i understood

  • @JimmyChungmusic
    @JimmyChungmusic7 жыл бұрын

    Thanks a lot!

  • @Akens888
    @Akens8885 жыл бұрын

    Thankyou!

  • @trenetae
    @trenetae2 жыл бұрын

    i like this problem, thx sir!

  • @doniaabdelmigeed2250
    @doniaabdelmigeed22503 жыл бұрын

    Really thank you ❤️

  • @VincentDuxD
    @VincentDuxD4 жыл бұрын

    The bomb, thx

  • @AlaizaF
    @AlaizaF3 жыл бұрын

    Thankyou so much, sir

  • @Mango_9934
    @Mango_9934Ай бұрын

    Thank u bro

  • @hrn8935
    @hrn89352 жыл бұрын

    To anyone who is wondering how to compute rotational inertia of complex systems lets say a cilindir and the axis was the geomteric center you integrate it with the limits being the ennds of a cylandir and the function relating how a tiny change in radius gives you a tiny change in mass

  • @maze._
    @maze._4 жыл бұрын

    6:37 What's an example where we can feel or intuitively understand that increasing the radius makes it harder to angularly accelerate an object? I'm having trouble grokking that.

  • @j_blue6784

    @j_blue6784

    3 жыл бұрын

    it's been a year but i'll try to answer Imagine you have two barbells that weigh the same but are different lengths (Illustration: O---O O----------------------O ). If you spin them (axis through center of mass and perpendicular to the rod) you'll notice that the shorter one is a lot easier to spin compared to the longer one. That's cause the weights are on average much further apart from the rotational axis on the longer one. Also, if you span both of them at the same time with similar angular momentum, the longer one's weights will move much faster, which shows that the longer one has stored more kinetic energy.

  • @kattamanasa1254
    @kattamanasa12543 жыл бұрын

    No one ,literally no has explained why is it I = mr² 😭😭😭thanks a lot

  • @fur1us556
    @fur1us5564 жыл бұрын

    7:50 don't forget that the string connecting the mass to the point has no mass😁

  • @Szhihihihihihi
    @Szhihihihihihi2 ай бұрын

    Thanks =]

  • @hrn8935
    @hrn89352 жыл бұрын

    Why does the t in troque look so weird im not sure if its you handwriting or the notation but it puts me off other than that great video

  • @bananastuff2840
    @bananastuff28404 жыл бұрын

    But when I try to push a door, it's easier to push at the further end from the axis than near the axis. What's happening here?

  • @mayalopez4008
    @mayalopez40084 жыл бұрын

    what if you don't have the masses and want to find inertia

  • @user-qg3ij8ts7e
    @user-qg3ij8ts7e7 ай бұрын

    ❤❤❤❤❤❤

  • @demaromavrazeb3111
    @demaromavrazeb31112 жыл бұрын

    Thank you so much!

  • @camid7403
    @camid74034 жыл бұрын

    why wasnt mass 3 torque calculated?

  • @abdullahumuthamzaogullar3315

    @abdullahumuthamzaogullar3315

    3 жыл бұрын

    Torque is just perpendicular force times distance. There was no force on mass 3, you could say 0*3 for its torque.

  • @bilalali7800

    @bilalali7800

    2 жыл бұрын

    @@abdullahumuthamzaogullar3315 Shouldn't the torque be considered as it has mass, so the force would be F=mg and then the torque would be 1*30N

  • @LorenzoB16
    @LorenzoB167 жыл бұрын

    6:09

  • @Ivan-pp8ib
    @Ivan-pp8ib3 жыл бұрын

    Imagine having time to dislike education videos

  • @andrewagita901
    @andrewagita9014 жыл бұрын

    big whoop

  • @cenaalan5825
    @cenaalan58259 ай бұрын

    Bad video from pedagogical point of view. Many places have "explanation gap". Author presumes that something is obvious (but not). Hard dislike.

  • @derjemand1021
    @derjemand10212 жыл бұрын

    Thanks a lot!