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wastedintime t1_j4slhdq wrote

Reply to comment by ellipsis31 in What happens to the energy of sound in space? by full_hammer

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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