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Comment on The Planet, some string and a bell.

TheActualDevil@lemmy.world ⁨1⁩ ⁨year⁩ ago

Okay, but what if there is no compression or expansion? What if it’s a rigid string already stretched out just enough to be expanded completely but not enough to move the bell? Or maybe a thin wire of the same weight?

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NeoNachtwaechter@lemmy.world ⁨1⁩ ⁨year⁩ ago

Okay, but what if there is no compression or expansion?

That means, the speed of sound is infinite in your material. It doesn’t happen in this world.

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Zippy@lemmy.world ⁨1⁩ ⁨year⁩ ago
Physics. The force you place on that string will effect the far end only at a rate no sooner than the speed of sound thru said medium.

The speed of sound in metal is about 17000 feet per second. Of materials on earth it has some of the fastest rates of transfer. But if you had a metal rod 17000 feet long and pushed one end a foot, the other end wouldn’t move a foot till a second later. It will compress.

Interestingly a neutron star has material that is so densely compacted that the speed of sound thru that material is approaching that of the speed of light.

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