Re: Want to prove E=mc²? University labs should try this!

On Wed, 20 Nov 2024 0:48:23 +0000, gharnagel wrote:

Might as well stick with Al and use a thicker wall.  That
puts all the pressure on the scales though, but I think that's
a much easier problem than weighing actual 455 nm light.  Just
keep pumping 5W into the cavity for 72 hours, and the hole
for introducing the 5W could be a sapphire disc with a 455 nm
transmission band, otherwise, too much energy would be lost.
>
What do you think, still out of bounds?  Yeah, I think so.

>
Use this site instead:
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https://aluminyumburada.com/en/aluminium-weight-calculation
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Weight of a sheet of 100x100mmx0.1mm (Alloy 5083) is 3.0 grams.
>
Not bad for my estimation (2 gr) for the weight of the cavity, with
inner surface of 7,850 mm², and thickness of 0.1 mm.
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And it will not melt. Not even heat enough for you to feel it.
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Most of the energy will be confined in the inner volume, not in the
walls, even with 99% reflectivity.