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

[@anthonymiu489]

Throughout my college years and until now, I didn't know what the sinusoidal waves represented (varying air particle oscillations). I just learned the equations and things taught to me. Thanks to your video I finally understand through your visual animations. Thank you so much!

[@wazulpoosh7187]

you have no idea how much it helped me.......i finally understood in like 15 minutes what otherwise would have took me more than an hour to understand.....thankx :)

[@youngwolf6896]

Man I love this video and the guy explaining it. I love the colloquialisms he uses to describe the particles - makes it so much easier to understand.

[@zayeedhumayun2502]

Finally, after watching this video I fully understood stationary waves open pipe. one of the videos that described this complicated topic easily

[@rahulm7453]

Beautifully explained with clear language and colors. Thank you

[@tysonchicken9232]

This video was so helpful. I’m taking an online Physics class and our textbook didn’t explain any of the vocabulary like node, antinode, and fundamental

[@shahnazhassan1885]

Finally someone who does not bore you! Thankyou!!

[@lukequinlan6732]

Khan Academy you are a God, literally my year 12 physics teacher who did an advanced physics degree cannot even explain this nearly as well....

[@beboshi69]

Thank you so much I wish I watched this before that suprise test I had today

[@arshiaslmn9986]

Thank you for great simple demonstration!

[@pookieboo9546]

THANKYOU VERY MUCH !!! I'm from Thailand, and I never understand about the waves until I found this clip. thank you

[@ahmadsyamimarsyad6431]

I like the oscillating like crzy part 🤣

[@men3ammohamadsemary287]

This guy explaining it is great

[@JohnLopez-jm3yy]

Good man, use the word "opened' when the other word in the same sentence is "closed". I like how a transparent tube reflects light (like in a fiber optic wire).

[@mysterioushoodedguy2332]

Holy crap dude thank you so much this makes things so much easier to understand, I don’t get why my school didn’t teach this in class

[@zahrashahabinezhad]

In open tubes, the second and the third harmonics wouldn't look like the ones you drew. Open tubes have antinodes at the two ends, vs strings which have nodes at the two boundaries. Great video!

[@joerectifier]

Fantastic video.....

[@arabindakumarpal3063]

how can one give such an awesome explanation!!!......

[@cine_cuts03]

Your classes are nice and understandable Plz add some more animation thus everyone could understand the concept easily So please add more animation Thank you 😊😊😊😘❤️❤️

[@Lee14G]

Why is Leonardo Dicaprio giving lectures?

[@dannyboy12357]

I thought it was owen Wilson.

[@anch95]

Yes ,Owen Wilson

[@BarryPennock]

Very illustrative!

[@njoodalbraik8186]

you're better than my prof. thank you a lot!

[@swarlychar]

I LOVE THAT YOU SKIP WRITING TIME TO SHORTEN THE VIDEO

[@nameless4630]

You’re the only person who allowed to understand the concept of a wave in a tube i was SO confused before this but now its all a clear image to me i fucking love the fuck out of u

[@sakshyamkataria599]

Loved yr explaination 🔥❤️

[@ThomasHaberkorn]

Dear Prof., I have a mix up in my terminology, I think you can clear things up. I did the following experiment: I have air flowing through a straight pipe. Pressure ratio between outlet and inlet is lower than the critical pressure ratio, which suggests flow velocity at the outlet is close to the speed of sound. I have recorded the sound of this process and analyzed the frequency spectrum. Suprisingly for me (but maybe not for you), the dominant frequencies are in a integer ratio to one another. So this would imply a standing wave behaviour.. but can it be called that? The air is moving at a great speed through the pipe after all. I search on the web for explanation, of little avail. Literature containing a mathematical approach would be greaty appreciated. Take care, love your videos.

[@kabouch]

2:51 a wave(sound) source is supposed to be placed at one end only; consequently, particles at the other end should follow the same oscillation pattern of their counterparts in front of the source; all particles oscillate rightward and then they all get leftward together. If particles in the middle do not oscillate, how energy is then transferred to the particles at the end opening!!!!!!!!!!!!

[@sabrinas.1302]

My question exactly! That part doesn't make sense...

[@prabirkumarghosh5550]

Thank you sir

[@TheMidno]

you sir are awesome !!

[@rb3198]

Very good video. The only question i have is why does air oscillate when both the ends are open, if it can just pass through straight?

[@Dan-gc3ke]

+Ronit Bhatia Yea I am confused on that as well... If it is open wouldn't the waves just leave the container?

[@educationalvideos4151]

I think atmospheric pressure is keeping air molecules compressed together. The pressure wave leaves the container (bands of high and low air pressure move outward) but the air molecules themselves are oscillating back and forth in roughly the same place.

[@yusufabbasi9447]

Man if velocity increases pressure at that region decreases and we know that high to low pressure thing...

[@earthschool463]

Which software used for making the drawings and animation? Thanks a lot for such great videos.

[@AbiMaslow5207]

thanks for getting me thru college physics

[@shin0098]

Thankyou so much. Our teacher did not explain it to us.But from this video i can finally understand.

[@DarkMaMonTV]

How does the standing sound wave in the both-opened ends tube happen? Why the sound wave not just pass through the tube like it normally pass through to air

[@cameronmills5763]

DarkMaMon that's exactly what i was thinking!!!!

[@satanikk5182]

DarkMaMon bro what the wave equation, look it up I'll get it

[@nimy7654]

DarkMaMon , there is an interface at the open ends. The density of air inside and outside the tube is slightly different. Therefore the wave reflects at the interface and superpose with the original wave producing a standing wave.

[@juliakim8226]

I do believe that (sound) waves are a transfer of energy, not matter. As such, a given particle will only vibrate slightly from its rest position, until it collides with an adjacent particle, transferring its kinetic energy. (This is my guess only).

[@damartimantilla]

Wave propagation depends on the medium through which the waves travel. When a wave encounters a change in the medium, such as going from the inside of the tube to the outside, the wave reflects. In a more fancy way of speaking, the "boundary conditions" change at the ends of the tube. This produces a reflection at the ends of the tube, both for open or closed ends. This is the same principle used for a sonogram. When the ultrasound encounters a change in the tissue, say from muscle to fat, part of the sound wave gets reflected at the boundary and the machine determines, from the time delay of this echo, the distance to the tissue boundary. This information is used to make a map or picture of the inside of the body.

[@sunandakumara2253]

thanks

[@macyoutubular]

I'm assuming you've spent some time with practical applications of Standing Wave concepts? If so, can you say that the application of the standing wave physics (math) allows a designer to produce a wind instrument that is more efficient, more powerful, or ........(?) Thanks

[@helloimnisha]

Great video... Great explanation... Thank you...

[@ALNOUR2011]

you are the best . keep going

[@roopalagarwal439]

Thnkx u saved me!..........

[@reezis1619]

Amazing explanation as always

[@PennDraken]

Top 10 Khan Academy Intros

[@Rene_Christensen]

You are assuming zero pressure conditions for the open end, which is okay-ish, but really only if there is vacuum outside the tube. In reality the boundary conditions involves Bessel and Hankel functions to take into account the end corrections.

[@joseargain2108]

Great

[@avacyy]

very good video

[@Brian-mf3ry]

I still dont understand how blowing over the double open end pipe creates a sound wave? how does the air oscillate and why does the middle air elements not oscillate?

[@muhammadyou5642]

This is due to production of standing waves.

[@xnovanoid57]

Blowing the air particles will displace them on the horizontal axis, now (on a double open ended tube) if you imagine that each adjacent air particle to the particle that is moving follows the directions of that particle, then collectively they move in the same direction. However if you air particles on the other side of the open ended tube move in the opposite direction with the same "force" (amplitude) then the particles in the middle all pulled both directions by the same amount and thus stay still. This is also true for the vice versa (if the particles on either end of the tube were moved in the opposite directions and hence why the standing wave is represented by two different waves with opposite displacements.

[@jackreid5970]

@@xnovanoid57 Thanks, but, Since you only blow in to one end, what's causing the particles on the other end of the tube to move in the opposite direction?

[@sunildeshpande6600]

What makes a wave get reflected at the open end? I have heard that the density and pressure of the air inside and outside is same .

[@bumbumtumtum230]

Nice

[@Salvatores-rl7ls]

Super sir

[@Vastasoceans7532]

THanks!

[@image5282]

goood so good

[@pralhadshenoy5901]

Draw equal amplitudes along positive and negative axes. It will then be easier to see that one fourth.

[@zeenoh5811]

wouldnt these resonant frequencies form with one node at the closed end and an antinode at the open end?

[@yuseffnehru8612]

Hi, is it true that the quartz crystal used to amplify the vortex, has a hexagonal shaped, arranged in a sphere. I believe the hexagonal shaped has something to do with the sound wave geometry.

[@macyoutubular]

in the last 10 seconds you say that if you put in 2 the equation represents your 2nd harmonic. Are you certain it is 2nd harmonic or is it actually 1st harmonic?

[@phenomenalphysics3548]

He's so funny 😂💞

[@crazybakri3047]

ILYSM THIS IS THE BESTEST

[@utkarshshankar3903]

amazing.

[@gabor6259]

But why do the particles in the middle not move? Why doesn't the group of particles oscillate back and forth as a whole? Or why don't they just rush through the tube?

[@miroslaw5615]

Why the wave is standing in both open end pipe?

[@harrisabdullah5769]

which graphical software is used here

[@tranceporter6176]

Is the fundamental counted as the first harmonic ? ... or is the next harmonic counted as the first harmonic ? like: Fundamental ... first harmonic ... second harmonic ... third harmonic or Fundamental (first harmonic) ... second harmonic ... third harmonic

[@TheFr3styler]

So why is this the same formular as for a string with 2 fixed ends?

[@davejones4740]

When is a tube not a tube. What defines a tube length? How long can a tube be, before it's not a tube. The tests you are doing are limited to a tubes length.Also If a tube is too long where sound or air pressure have resistances over distance, no sound would be heard or air pressure felt.

[@jannatzeeshan9769]

Fundamental frequency and fundamental wavelength are not same. 10:12

[@xxxxxxxxxxxxxxxxxx1127]

what happens if both ends are closed. so nodes at both ends. example: a rope

[@muazzamshaikh2049]

I don't grasp the fact that why the air molecules in between won't oscillate... As there is a wave travelling in parallel direction to the direction of oscillation and there's space for it to move...?

[@mjylove2]

soooooooooooooooo goooooooooooooooooooooooooooood

[@Chelsea-gs7qj]

Are the terms fundamental wavelength and fundamental frequency the same? Could you explain why or why not? #MCATprep

[@dannyboy12357]

If you have one you can derive the other.

[@sachinrath219]

why do we blow horizontally in the bottle top,how the air reaches inside the bottle,will standing waves be formed f blown into the bottle,thanks.

[@vishaljain4915]

at 11:00 there are 3 anti nodes right?

[@purnashrestha3199]

❤️

[@pulkitmidha5710]

Whats that crazy pink line at 5:56?

[@lonewolf604]

I was slightly thrown off at first, the drawing of the graph going up and down and the air particles going side to side.

[@sanketmehta1666]

Where can i get the ppt of the same????

[@roseb2105]

why doe the air not move out from one end of tube to other?

[@arjavgarg5801]

Dude what about the superposition?

[@kotakduabelas6236]

if i have different distance for each nodes, can i calculate wave length use L=n/2*lambda?

[@shockwave2477]

10:50 Won't there be an antinode in the center?

[@marcospimentel6098]

the bottle is a bad example because it is very different from the tube. The bottle is a Helmholtz resonator and will behave like a mass-spring system rather than standing waves in a tube.

[@harlbertmayerh7523]

Like crazy!!!!! LOL

[@sabrinas.1302]

Your ability to explain things in an easy way is off the mark. This time though, I couldn't understand something. If the air particles at the middle part of the tube doesn't move, how is the energy transferred to the other end? Also, what makes the energy transferred and the particles oscillate in that specific way? Is there something that's missing here?

[@Amoeba_Podre]

Did you discover something?

[@FasAntick]

I just dont get what the x axis is

[@shivanisharma6943]

👍👏

[@casablanca007]

Joss

[@KeltikManEater]

why dont they just say that

[@syedusman5285]

Any one writing neet 2019

[@rkguptasmart442]

😧 fuck! explain theory bro

[@khanaisha9567]

I like the name DANCING WAVE 😂😂

[@frustoo]

i didn't understand anything.not useful

[@925LY]

that's a problem on your side.

[@sairamesh5521]

Just understand. That's all you need to do.