I know that sound doesn’t travel in a vacuum, you can hear it muddled in water, and different temperatures of air transmit better. But which is the “best”. Let’s say you had a speaker and a microphone in an enclosed case filled with whatever you wanted, which would be the best medium to ensure the best sound transmission?
This is right.
Water or metal, take your pick: both massively-outperform air.
Wikipedia often has speed-of-sound for elements, iirc…
…
glancing at this, now I think that hexagonal-diamond would be most-efficient & fastest…
https://en.m.wikipedia.org/wiki/Speeds_of_sound_of_the_elements
Hexagonal-diamond is diamond, but with the carbon links in a different pattern.
Apparently you make it either 1 of 2 ways:
either alternate the orientation of layers of graphene, before compressing ( with explosives ) into diamond,
or you put carbon into a meteor, & crash it into a planet or something.
IOW, it forms about 60x as quick as normal-diamond, and takes insane pressure to do it.
Normal diamond would probably be next on the scale.
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