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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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
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!
I am so grateful for ALL of your videos - they're the ones getting me through my physics exams! Thank you so much!
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.
exactly
explanation regarding compression,rarefaction,pressure variation,and standing wave would be highly appreciated
When people complain about the clarinet not having an octave key so u show them this video
I have been struggling with this topic, you just made me understand this. Thank you so much, may God bless you🙏🏽
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.
Best video pertaining to harmonics, in fact none of the other Physics videos on TH-cam explained this topic in particular this thorough
by far the best video I've seen on this concept. THANK YOUUUUU
Ur my hero When it comes to Physics!!!
This is very helpful and I have told my friends about this thanks a lot
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
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?
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.
You have observed wrong, amplitude decreases but frequency still increases
You're are awesome David SantoPietro!
1:45 you could say that nodes have "node" displacement.
Thank youuuuuuu sooooo much.. i really tried to find this in book but i couldn't understand .. your video helped me a lotttttttt ❤
thank you so much!
Thank you so very much, you make physics so easy!
You are a great teacher for me. Thanks a lot.
Thank you sir
Wow... thanks a lot..m so glad I watched this ❤️
Good one
Why did the third wavelengths rarefraction not come closer to the bottom of the tube?
this video is awesome thank you so much
Very good ! ty
Thank you!! Your video helps a lot!!
Thank uuuu
Thank you
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
this was soo muchh helpful. so much. thanks a ton. books suck.
Thank you so much
Informative
You are amazing!
Great explanation as usual!!!!! Love khanacademy
Good
standing waves are formed by superposition of reflected waves,here there are no reflections,pl clarify,thanks.
why is it necessary to have an end at the node?
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)?
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 :(
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.
Please a choke end of a resonator is like a closed end?
NODEsplacement :)))
Malak Tumeh NO.
You mean 4L/(2n-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)
The harmonics are missing... the overtones are subsequent!
Why do you have to blow over the opening rather than into it.
Why always antinode in open organ pipe and node in closed organ pipe????
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.
you are so fkin cool
My teacher sucks , she never tried to help me, I understand the concept after this video.
my physics teacher just drew the displacement graphs and done thats all xd
one thing i never understand is that " why waves reflects form the open end?" could anybody help me?
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 .
I made the total likes 800
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?
@@zainabhussain3887 iirc it's blowing inside the bottle, this produces standing waves. A better model is to put a tuning fork near it
@@Upgradezz thank you so much I thought he is blowing horizontally and due to burnoulis the air trying to move out and got confused 🙈
@@zainabhussain3887 for questions on physics try asking on physics stack exchange.com. BTW how did Eid go?
@@Upgradezz im using physics stack. And yeah Eid went pretty good✨💫
What if the first one was actually zero?
U r just great......
R u Pakistani???
"It's hard to see"..... because the drawings aren't even
.....