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ellipsis31 t1_j4s9a0a wrote

If you yell in space the energy goes into the gases that you are expelling as heat. If you tap a tuning fork in space the energy pretty much stays in the tuning fork as heat until it can be radiated away as infrared.

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full_hammer OP t1_j4sclec wrote

Ah that makes sense, thanks for the tuning fork example. That really helped it click

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quaste t1_j4u5j45 wrote

Just think about it as: the dampening effect of the surrounding air doesn’t exist, so energy stays within its source longer.

Or think about water instead of air and moving in water (sound is just movement or created by movement) vs outside.

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wastedintime t1_j4slhdq wrote

So, since the tuning fork doesn't have the resistance from the air, which it moves to make sound, will it vibrate for a very long time?

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Chemomechanics t1_j4sm8iq wrote

A while, but not forever. Even elastic deformation dissipates a little heat (termed internal friction or sometimes mechanical hysteresis).

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[deleted] t1_j4swaiu wrote

[deleted]

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zebediah49 t1_j4t72hl wrote

Minimally faster. Without the air resistance it'll sit a bit closer to ideal resonance -- but even in air it's extremely close. The mechanical properties of the fork are what dictate the frequency, and those remain unchanged.

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aspheric_cow t1_j4tpg0p wrote

A tuning fork would not vibrate measuralby faster in vacuum. If air resistance changed its vibration frequency (pitch) by a measurable amount, it would also vibrate slower when its vibration amplitude is less - i.e. its pitch would go down as the vibration decays.

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Mord42 t1_j4u2r5i wrote

> A tuning fork would not vibrate measuralby faster in vacuum.

I'm being incredibly pedantic rn but since a vacuum slightly decreases the damping, the damped frequency would be ever so slightly higher than if the air was there.

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Force3vo t1_j4u9qtb wrote

Which is why they said measurably faster.

It would be faster but not in a way that's really meaningful.

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Force3vo t1_j4u9tl7 wrote

What's up with people with zero knowledge about things talking like they are specialists lately?

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Saidear t1_j4sww6h wrote

That would imply continuously increasing energy in the fork. While the initial vibration might be faster, and it will fall off slower.. the energy will be decreasing and thus, any material fatigue minimum

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Mord42 t1_j4u2u2x wrote

Even if you increase the energy the vibration frequency would not change. The frequency is not related to amplitude

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TerminationClause t1_j4u2ek4 wrote

You know, I woke up this morning and didn't have a sudden urge to take a tuning fork into a vacuum, thanks. That's what my life has been missing. I actually have a couple of large tuning forks if someone can supply me with a vacuum chamber.

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DragonKnightAuroran t1_j4uup7d wrote

So you're telling me, if I was loud enough in space I could breathe fire?

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Baalthoros t1_j4vfrz4 wrote

You would expell a fine dusting of ice crystals and gas which would cause you to start spinning from the force of the gas expelled. You would then die painfully over a few minutes from exposure to vacuum.

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GolfballDM t1_j4vta9j wrote

> You would then die painfully over a few minutes from exposure to vacuum.

If you're unconscious, is it really pain? Is it pain all the time, or just when it can be perceived?

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Baalthoros t1_j4x4il7 wrote

From what ive read it take about a minute for curculation to stop. So you dont instantly black out, however the process you go through would be painful the second it started. So lots of fun pain there. Also, the body and brain respond to pain stimuli even when you are not concious. So yes, still pain until you die. Plus, if you are in open space in a solar system within a certain distance from the local star while it happens you get to experience one half of you boiling from sunlight while the other half freezes.

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skurk t1_j4vgrsu wrote

This may be a silly question, but why infrared?

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the_agox t1_j4vqzs4 wrote

The short answer is blackbody radiation. Everything naturally glows a little bit, and that glow changes with its temperature. At "room temperature", it's in the infrared (Planck's Law). As temperature increases, so does that frequency of the radiation. If the tuning fork was heated to 500ish degrees Celsius, it would glow a dull red.

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[deleted] t1_j4up4z5 wrote

As well as the vibrations through your own body. The sound has to travel through something and given the lack of air except that which you expel, most of it just moves through you.

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roosty_butte t1_j4uszj7 wrote

If you moved that tuning fork directly into a pocket or air, would it produce its tone?

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Buddahrific t1_j4wfdcw wrote

A "pocket" of air would want to dissipate from it's own pressure in a vacuum/near vacuum. If one were to exist long enough to stick a tuning fork into it, it would dissipate faster. Think like a pile of sand on a vibrating table (not a resonating table with high and low energy standing waves, but just a table where the whole thing is vibrating at the same rate).

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roosty_butte t1_j4wi5a2 wrote

Nah, I mean as a purely theoretical situation. The bubble of air is not affected by the vacuum of space.

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Buddahrific t1_j4wma2y wrote

Pressure plays an essential role in sound (sound is pressure), so it's hard to separate the two. A vibrating tuning fork would transfer kinetic energy to anything that gets close enough to touch it, including a pocket of air that is somehow held together in a vacuum. If you had a microphone inside that, I think it would pick up those vibrations as sound.

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Vicorin t1_j4wvjrs wrote

So in space, could I beat on a tuning fork until it was red hot? How long does it take for the energy to radiate out?

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ellipsis31 t1_j4xha2n wrote

Almost certainly yes, heat dissipation is a huge problem in space/space travel.

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zamach t1_j4vcstt wrote

Unless it's slightly asymmetrical and over time some of the vibration turns into rotation.

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LampardNK t1_j4vflip wrote

so if you yell loud enough can you spit fire like a dragon?

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10113r114m4 t1_j4u5wd4 wrote

I read that second sentence as "if you fap a tuning fork" and I was like "yes, yes, then what?" Just to realize I misread

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vox_mechanika t1_j4uj4dj wrote

Wouldn't you just end up with an extremely satisfied tuning fork... and a sticky mess??

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