|jreid - 2014-10-31 |
It's the sound that makes it for me. The smacking of 700,000 lbs of thrust then sudden silence, shocked gasps from the crowd, then fucking WHAM and screams of confusion and horror.
|kamlem - 2014-10-31 |
If it broke the tablet that the guy was holding up to film the rocket then the expense was worth it.
|dairyqueenlatifah - 2014-10-31 |
|oddeye - 2014-10-31 |
Can someone please explain how this happens? (not the crash, the blastwave)
thanks for the detailed answer.
How is it possible that they could be "blasted" so far away and for it to be so loud from that distance?
Are they using speakers to hear from a microphone that is near the launch pad? If so, wouldn't the speakers blow up LONG before reaching that kind of power? Otherwise they would have to be like 100' tall!!
Sound is essentially just a pressure wave moving through air. The shock-wave created by that explosion moved at the speed of sound, hence why it got there after you could see the explosion.
They only need speakers for the countdown- even when they go correctly, rocket launches are crazy loud. In this case, all of the fuel going up at once creates massive heat, which in the localized area raises the air pressure super rapidly, creating a rapid outward movement of surrounding air.
I'm not a scientist, so if anyone knows better, feel free to point out that I'm wrong. Or right, I enjoy affirmation.
Probably magic. NASA is big on the magic. They don't talk about it.
The man puts his erect penis into the womans vagina and he ejaculates. 9 months later, BAM!
That's cool and all and again I appreciate your serious answers here but how the fuck can you hear it from so far away? LOUD trucks go zooming down the road like 2 blocks from where I live and you couldn't hear them even if you tried.
It shouldn't be possible for your eyes to hear that far away unless there is some kind of different physical law that is being applied here.
A rocket launch is about 165-170 decibels. A bigass truck is about 80-85 decibels. You might think "oh, so a rocket is only twice the loudness of a truck" but there's the catch: decibels are on a logarithmic scale - so a truck would be in the ballpark of a power ratio of 1,000,000, whereas a rocket would be closer to a power ratio of 10,000,000,000,000,000.
And that's just a normal launch, where all that fuel burns over a period of minutes. Blow it all up at once and you're gonna get a MUCH louder sound.
tl;dr: rockets are motherfucking LOUD. Louder than anything you've ever heard. And exploding rockets are even fucking retardedly louder.
Think about the amount of energy it takes to send several tons of material into orbit. Think about all that energy being expended at once.
It's no different physical law, it's just A LOT of energy. Big explosions can be heard from many miles away, nuclear bombs can be heard from dozens or even hundreds of miles away.
Very interesting stuff!!
Despite the loudness of exploding rockets traveling so far how come we are still able to hear it from 1.5 miles away? Our hearing doesn't reach that far ya know, that's what I'm getting at. Just as we can't see normal sized writing from more than 5 ft away, we can't hear a car driving by from the basement.
That's what I'm stuck on, it shouldn't be possible for the range of our hearing to extend that distance.
Yet it is?
Think of sound like waves in a pond. You throw a tiny pebble in the water, little ripples will spread out a few feet, getting smaller as they spread. Throw a 500 ton boulder in the water, there'll be a fucking tidal wave.
Same thing for sound - the air acts same as the water, transmitting those waves from the source of the sound (ie the pebble) outward. The bigger the sound-maker, the further and louder the sound will go.
Ok, so hmmm... interesting, waves in a pond.
How come when I mutter something behind someone's back they don't hear me? Shouldn't my fat based insult ripple out around me, even behind me, and reach those those flabby ears of his? Yet every time Jorge has back to me he has never heard me asking him if that fat, greasy fuck uses lard for soap. I have no idea.
That makes sense but at the same time it doesn't.
I don't understand how jumping out of a plane a mile up without a parachute would kill me. I hop out of the bus every day and I'm just fine! They're both just vehicles. Explain THAT magic to me, "scientists".
Our ears are geared towards listening to what we're looking at- whatever you're looking at is probably what you want to hear. Whatever is behind you is probably something you're comfortable turning your back to.
But yeah, as has been stated above, sound keeps scaling up and up and up.
I think I'm getting it now dudes, thanks to all the help you folks are giving me. So I wouldn't have to have my ear pressed against Rita's pungent gusset to hear queef cause the divine noise would radiate out and ,much like this video, blast us into dust with it's brilliance.
But if what you say is true then how come no one else hears Her farting out my golden jizz everytime I close my eyes? Shouldn't their ears hear that too or does the whole world have it's back turned?
This one's for oddeye.
The speed of sound is fairly straightforwardly derived by examining an infinitesimal pressure wave as it propagates through the air. (More generally, for any fluid.) However, shock waves are not infinitesimal, so we can throw most of that right out the window. Shocks are finitely large "overpressure" phenomenon, where sound waves are differential "plus/minus" excursions from the mean pressure.
Shock waves form when there is a arge unsteady "push" on a flow. (Here's an interesting fact: No part of a whip exceeds the speed of sound, yet a crack is produced by the *acceleration* of the end of the whip in the air. I know. Whoah.) The model we use to understand this is an "infinitely long" gas-filled tube with a piston in one end. If the piston is accelerated toward the gas in the tube, that information is propagated away from the piston, through the gas, initially via infinitesimal waves of positive pressure. As the piston continues to accelerate, the gas on the face of the fluid is being compressed. If we think of a continuous push as a series of discrete pushes, then each discrete push results in a new wave that is, initially, *behind* the wave in front of it. These waves are all differentially small.
Now, each of these compression waves is in the wake of the wave in front of it. That is, the wave in front has already transmitted the work of compression to the flow, and the succeeding wave is propagated in that medium. Because each wave *compresses* the flow, the Ideal Gas Law tells us that the temperature of the gas rises behind each wave. Because the speed of sound is only a function of temperature in an ideal gas, "later" waves propagate more quickly than earlier waves. (Hot air transmits sound more quickly than cold air, in a nutshell.) Successive differential waves then *catch up* to the initial wave, and their compression, and therefore heating, actions simply sum.
The upshot of this is that there is a "shock roll-up distance" that is required for a shock wave to form from an impulsive motion. (In the Mt. St. Helens blast of 1980, for example, persons near the mountain heard a rumble, but persons farther away heard a blast.) Once enough of these waves pile up, you can easily exceed the speed of sound in the gas medium, both because you've left the theory of small waves and entered a realm of significant pressure differentials, and also because the speed of sound behind the shock is faster than the speed of sound in front of the shock.
Also of note is that a shock wave is one of the closest things to a singularity in nature that you are likely to encounter. The flow completely accommodates to the new pressure and tempuratue conditions across the shock face, which is about 3 "mean free paths" thick, which ends up being about 200 billionths of a meter.
Luckily, the inverse square law in the free atmosphere (and the inverse law close to the ground) handily dissipates shocks over long distances, basically as a result of the continuity equation.
Hope this helps. I'm such a dork.
***** for knowledge
I felt myself getting smarter while I read that.
I appreciate all the replies that are trying to be helpful, even the longer ones which I didn't read...
BUT YOU GUYS JUST AREN'T LISTENING TO ME!!
Go back and re-read what I've written and you will see what I am trying to say and where you have gone wrong. How are we able to hear an explosion from so far away when our ear can't hear that far? I know it's POSSIBLE but every explanation you've guys have tried to give me has been IMPOSSIBLE.
If our ears could hear that far then I should be able to hear people talking TWO TOWNS OVER but I can't so THERE GOES YOUR ANSWER.
Now, PLEASE, give me a REAL answer that's not something silly like "magic" and shit, just simple, basic FACTS as to why this happens. Thank you and sorry for the rant when you are only trying to help.
I think I worked it out dude, it's like on TV when you hear footsteps from a mile away. The BLAST knocked everyone down but the actual explosion was just dubbed on the video from the microphone recording at the launch pad.
So yeah, sound ripples and that but also too far to hear it. So we were ALL right. This is why I love this place, you can have a serious discussion on physics and science etc. and only a few idiots try to derail it (and they get largely ignored)
Oddeye, it's not that your ears are straining to hear it from far away. The sound is coming at you like a giant wall, so when it reaches you, you can definitely hear it. Stuff from two towns over would dissipate before it even reached you, but 1.5 miles away from a giant explosion isn't far enough to dissipate it, hitting you with the full force. Think of it like how you see lightning, then the thunder hits and shakes your house.
tldr; Sound comes to you
Oddeye, the reason we aren't listening to you is because you're too far away and we can't hear your voice.
Can I help it if the Truth about how shockwaves form has been rejected by you? No, I cannot. You must come to understand it yourself, though experience and error.
Quit lying with your middle school "science". My eyes can't see a candle flame from 2 miles away, yet I'm supposed to believe that the flame from a rocket explosion would be visible? In daylight no less! What, are my eyes just magically straining to see it? HUH?
|John Holmes Motherfucker - 2014-10-31 |
I LOVE THIS VIDEO! It almost feels like I'm there, crapping my pants.
|Caminante Nocturno - 2014-11-01 |
Well, at least it made for a memorable outing.
Sanest Man Alive
It's a setback, sure, but I'm just glad it wasn't another space shuttle.
|il fiore bel - 2014-11-01 |
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