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Sound

ciechanow.ski

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Re: Sound

#61

Post by jcims »

jarenmf wrote: post #56
jcims wrote: post #30

I love it when I'm halfway through something and take a second to pause and wonder why someone put so much effort into it, and them I appreciate that they did. This is amazing. One thing that surprised me the first time I learned it is how 'dense' air is under normal circumstances. The 'mean free path' is the mean distance that a particle travels before changing velocity (typ due to collision). The mean free path of…

I was able to reach 10^-7 mbar with a good vacuum system and I though I would have few thousand molecules, turns out there is a billion (10^9) molecules per cubic centimeter at that vacuum level.

And yet somehow, as far as we know, the energy of every molecular collision is faithfully preserved during a supernova, when effectively the entire volume of a star collapses into its core in less then a second.

Reality is very strange.

Re: Sound

#62

Post by lozzo »

Interesting. Just earlier I went to Bartosz website to see if there was anything and there was not... and then he publishes sound and I see it here on hackernews. I am going to enjoy this. thanks

Re: Sound

#63

Post by armchairhacker »

sgraaf wrote: post #52

Bartosz' blog posts are in a league of their own. They way he is able to explain complex subjects by starting from first principles, gently adding more and more layers, with beautiful, custom-made figures and animations is truly, literally, awesome. I strongly recommend supporting the author via his Patreon if you enjoy his blog posts.

The article on mechanical watches had so much depth and such good explanations I thought he was a mechanical watch engineer or enthusiast who happened to also have web design, 3d animation, and writing skills

Re: Sound

#64

Post by woliveirajr »

> at room temperature the average velocity of a particle is a staggering 460 m/s so to make the particles visible I’m showing their motion significantly slowed down

Isn't 460 m/s the speed of the shock waves?

I mean, it you make some "air particle" move, it'll hit a nearby particle, and so on, and this wave has a speed of 460 m/s. In a solid object (wood, for example) the particles are close together and the speed will be greater. If you remove air particles it'll decrease the pressure and the speed will be slower...

Re: Sound

#65

Post by naillo »

Nothing really to say about this other than excellent work again and this really inspires me to make amazing web-based material in ways I haven't really experienced since the ~2012 era.

Re: Sound

#66

Post by mabbo »

> As a side note, I’m using metric units here, but you can *switch* to the imperial system if you prefer.

Clicking on the word 'switch' does exactly that. That's a delightful and clever touch that of course comes from Bartosz Ciechanowski.

Re: Sound

#68

Post by Erwin »

I was surprised by how much I was surprised by the very first fact -- that air molecules move around at extremely high speed of 450m/s, but just bump into each other cancelling this speed out, and this speed is based on pressure & temperature.

And it's due to this speed, despite air's low density, the force air exerts is enormous -- equivalent to 10 tons per square meter. Somehow, the human sandwich does not explode nor implode due to equivalent pressure coming from the other side and inside.

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