Standing waves in closed tubes | Mechanical waves and sound | Physics | Khan Academy

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  • เผยแพร่เมื่อ 25 ส.ค. 2024
  • Find out why you can make music by blowing into empty bottles. Created by David SantoPietro.
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ความคิดเห็น • 71

  • @mjylove2
    @mjylove2 8 ปีที่แล้ว +57

    sooooooooooo gooooooood i am so impressed by the way you teach this abstract topic so easy! It has been really tough time for me to understand the idea of standing waves in open pipes and one closed pipes. now after watching your lesson, now i compeletely get it! i am so happy. so much thank you for you from South Korea

  • @user-mh4ew5km4i
    @user-mh4ew5km4i 6 ปีที่แล้ว +12

    OH MY GOD IM SOO SOOO GRATEFUL!!! I’ve finally understood this! You’re MUCH MUCH better than my school’s teacher AND my home tutor!! THANK YOU VERY MUCH!! I really appreciate these videos a lot!

  • @MalakTumeh
    @MalakTumeh 5 ปีที่แล้ว +6

    I am so grateful for ALL of your videos - they're the ones getting me through my physics exams! Thank you so much!

  • @kabirkanha
    @kabirkanha 7 ปีที่แล้ว +10

    Why could he not have written the formula as λn = 4L/(2n-1) ?
    That would work for all integral values and you wouldn't have to worry about any missing harmonics.
    That said, this video is amazing, like all the other ones from Khan Academy.

  • @904saf
    @904saf 8 ปีที่แล้ว +5

    explanation regarding compression,rarefaction,pressure variation,and standing wave would be highly appreciated

  • @JohnSmith-iu3jg
    @JohnSmith-iu3jg 6 ปีที่แล้ว +13

    When people complain about the clarinet not having an octave key so u show them this video

  • @elizabethmbou3546
    @elizabethmbou3546 3 ปีที่แล้ว +1

    I have been struggling with this topic, you just made me understand this. Thank you so much, may God bless you🙏🏽

  • @tedwashburn
    @tedwashburn 4 หลายเดือนก่อน

    I need to see a non-linear analysis i.e. one that shows how low amplitude waves can travel faster than high amplitude waves, overtaking them and leading to a pulse with a very high peak. I can hear this effect when a trombone is played loudly but also with a trumpet and to a lesser extent a cornet. I think it has to do with the long cylindrical (not conical) section of a trombone.
    A similar phenomenon occurs with water waves when they move into a shallower region. Low amplitude waves overtake the waves ahead of them and a crest forms which becomes unstable and the wave crashes on the shore.

  • @BOBO_4869
    @BOBO_4869 5 หลายเดือนก่อน

    Best video pertaining to harmonics, in fact none of the other Physics videos on TH-cam explained this topic in particular this thorough

  • @mariahj9449
    @mariahj9449 3 ปีที่แล้ว +1

    by far the best video I've seen on this concept. THANK YOUUUUU

  • @Arham1716
    @Arham1716 ปีที่แล้ว

    Ur my hero When it comes to Physics!!!

  • @ARCANEmateCLAN
    @ARCANEmateCLAN 9 ปีที่แล้ว +1

    This is very helpful and I have told my friends about this thanks a lot

  • @aryag1989
    @aryag1989 2 ปีที่แล้ว

    Your just amazing I was so confused in class and now that i've watched this video I feel like I actually understand the concept finally

  • @gayanthaekanayake8068
    @gayanthaekanayake8068 7 ปีที่แล้ว +8

    when you use a glass jar with different heights of water, and strike it with a metal, you get a higher pitch as the water level is lowered unlike what is mentioned here. Why is that?

    • @TheMasterOfWishes
      @TheMasterOfWishes 5 ปีที่แล้ว +4

      Gayantha Ekanayake i guess because in that case, what’s oscillating is the jar+water so less water means a smaller medium, which in turn means a higher pitch. Whereas in this video it’s the AIR inside the bottle that oscillates and more water means less air, so a higher pitch.

    • @mr.mirror1213
      @mr.mirror1213 4 ปีที่แล้ว

      You have observed wrong, amplitude decreases but frequency still increases

  • @khazeemahafeez6811
    @khazeemahafeez6811 6 ปีที่แล้ว

    You're are awesome David SantoPietro!

  • @nihilisticalbino
    @nihilisticalbino 2 ปีที่แล้ว

    1:45 you could say that nodes have "node" displacement.

  • @radiakhan5286
    @radiakhan5286 6 ปีที่แล้ว +1

    Thank youuuuuuu sooooo much.. i really tried to find this in book but i couldn't understand .. your video helped me a lotttttttt ❤

  • @oatmeal9227
    @oatmeal9227 2 ปีที่แล้ว

    thank you so much!

  • @sanhitasaxena1542
    @sanhitasaxena1542 3 ปีที่แล้ว

    Thank you so very much, you make physics so easy!

  • @ASHOKKUMAR-sh3bz
    @ASHOKKUMAR-sh3bz 6 ปีที่แล้ว

    You are a great teacher for me. Thanks a lot.

  • @NikhilSharma-wd4ni
    @NikhilSharma-wd4ni 3 ปีที่แล้ว

    Thank you sir

  • @aishaadams4465
    @aishaadams4465 3 ปีที่แล้ว

    Wow... thanks a lot..m so glad I watched this ❤️

  • @centerofphysics9909
    @centerofphysics9909 3 ปีที่แล้ว

    Good one

  • @altonmyrie7392
    @altonmyrie7392 8 หลายเดือนก่อน

    Why did the third wavelengths rarefraction not come closer to the bottom of the tube?

  • @roseb2105
    @roseb2105 5 ปีที่แล้ว

    this video is awesome thank you so much

  • @sahraouihamza1807
    @sahraouihamza1807 5 ปีที่แล้ว

    Very good ! ty

  • @iamgroot2810
    @iamgroot2810 7 ปีที่แล้ว

    Thank you!! Your video helps a lot!!

  • @nimshanayomi4221
    @nimshanayomi4221 ปีที่แล้ว

    Thank uuuu

  • @quriositysquared1028
    @quriositysquared1028 5 ปีที่แล้ว

    Thank you

  • @bhuven1709
    @bhuven1709 5 ปีที่แล้ว +1

    won't it be better tomato the wavelength consecutive and make the formula; 4L/2n-1
    btw these vids helped me a lot and improved my physics marks
    13 year old from Singapore

  • @arshisid47
    @arshisid47 9 ปีที่แล้ว

    this was soo muchh helpful. so much. thanks a ton. books suck.

  • @PhysicsVlogs
    @PhysicsVlogs 7 ปีที่แล้ว

    Thank you so much

  • @fazleahadusafxai9418
    @fazleahadusafxai9418 5 ปีที่แล้ว

    Informative

  • @wlh2476
    @wlh2476 7 ปีที่แล้ว

    You are amazing!

  • @sshirish9167
    @sshirish9167 6 ปีที่แล้ว

    Great explanation as usual!!!!! Love khanacademy

  • @kittureddy7773
    @kittureddy7773 6 ปีที่แล้ว

    Good

  • @sachinrath219
    @sachinrath219 4 ปีที่แล้ว

    standing waves are formed by superposition of reflected waves,here there are no reflections,pl clarify,thanks.

  • @memelordozai8553
    @memelordozai8553 7 ปีที่แล้ว

    why is it necessary to have an end at the node?

  • @Saptarshi.Sarkar
    @Saptarshi.Sarkar 4 ปีที่แล้ว

    But what happens if an open pipe has a hole at the center? (Like a flute) Should we get an antinode at the point of the hole at all times? Or does that act like cutting and making the pipe shorter (making it half the size)?

  • @user-sd4no4ok8n
    @user-sd4no4ok8n 8 ปีที่แล้ว +1

    1)What do you mean by "the length of the tube determines which wavelengths are allowed? i mean, if i put a sound source on the open end of a bottle that has a frequency other than Vn/4L what happens to the air in the bottle? Is a wave not created? the air molecules have got to move but what happens?
    2) Any idea what happens during speech? the source is in the middle of a closed tube which has many parts of different lengths and volumes. as the air passes through them they can be considered seperately as open ended tubes.
    I'm so confused :(

    • @xnovanoid57
      @xnovanoid57 6 ปีที่แล้ว

      So i don't know what "speech" is, but regarding your first question. The point is that only STATIONARY Waves can form under those frequency's ie. when the frequency and length of the tube is such that wave has a length equivalent to one of the harmonics. Sound waves can of course still form its just that a stationary wave won't.

  • @Anatoliy-3D
    @Anatoliy-3D 7 ปีที่แล้ว

    Please a choke end of a resonator is like a closed end?

  • @MalakTumeh
    @MalakTumeh 5 ปีที่แล้ว +1

    NODEsplacement :)))

  • @gabor6259
    @gabor6259 3 ปีที่แล้ว

    You mean 4L/(2n-1)?

  • @ricerocket27
    @ricerocket27 9 ปีที่แล้ว +1

    I don't really understand the "missing harmonics" idea. It seems to me that every node added is a subsequent harmonic with wavelength equal to 4L/(2n-1)

    • @ArushiDhawanxoxo
      @ArushiDhawanxoxo 9 ปีที่แล้ว

      The harmonics are missing... the overtones are subsequent!

  • @mosab643
    @mosab643 5 ปีที่แล้ว

    Why do you have to blow over the opening rather than into it.

  • @missmak559
    @missmak559 6 ปีที่แล้ว

    Why always antinode in open organ pipe and node in closed organ pipe????

    • @pragyakhanna3331
      @pragyakhanna3331 6 ปีที่แล้ว +1

      This is because in an open organ pipe the particles are allowed to displace maximally which means there is an antinode.But, in a closed organ pipe the particles are not allowed to move which means there is a node.

  • @pong_66
    @pong_66 5 ปีที่แล้ว

    you are so fkin cool

  • @smitgaikwad2904
    @smitgaikwad2904 5 ปีที่แล้ว

    My teacher sucks , she never tried to help me, I understand the concept after this video.

    • @pong_66
      @pong_66 5 ปีที่แล้ว

      my physics teacher just drew the displacement graphs and done thats all xd

  • @mrTrthapaliya
    @mrTrthapaliya 9 ปีที่แล้ว +5

    one thing i never understand is that " why waves reflects form the open end?" could anybody help me?

    • @darknebulae8037
      @darknebulae8037 7 ปีที่แล้ว +1

      Because there is a difference in the densities of the medium . A portion of the wave moves backwards and some of it moves forward without any phase difference and offcourse a reduced amplitude .

  • @Upgradezz
    @Upgradezz 3 ปีที่แล้ว +1

    I made the total likes 800

    • @zainabhussain3887
      @zainabhussain3887 3 ปีที่แล้ว

      Hey can you please tell me what did he mean by blowing, blowing air horizontally on top of the open soda bottle or blowing inside a soda bottle?

    • @Upgradezz
      @Upgradezz 3 ปีที่แล้ว +1

      @@zainabhussain3887 iirc it's blowing inside the bottle, this produces standing waves. A better model is to put a tuning fork near it

    • @zainabhussain3887
      @zainabhussain3887 3 ปีที่แล้ว

      @@Upgradezz thank you so much I thought he is blowing horizontally and due to burnoulis the air trying to move out and got confused 🙈

    • @Upgradezz
      @Upgradezz 3 ปีที่แล้ว +1

      @@zainabhussain3887 for questions on physics try asking on physics stack exchange.com. BTW how did Eid go?

    • @zainabhussain3887
      @zainabhussain3887 3 ปีที่แล้ว

      @@Upgradezz im using physics stack. And yeah Eid went pretty good✨💫

  • @ProphecyOfAlice
    @ProphecyOfAlice 4 ปีที่แล้ว

    What if the first one was actually zero?

  • @missmak559
    @missmak559 6 ปีที่แล้ว

    U r just great......
    R u Pakistani???

  • @orlandoarriaga7148
    @orlandoarriaga7148 ปีที่แล้ว

    "It's hard to see"..... because the drawings aren't even

  • @subhadeepmukherjee5408
    @subhadeepmukherjee5408 6 ปีที่แล้ว

    .....