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# another perpetual motion idea

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this probably has been tried, use a hour glass with them separated in the middle,

use a water wheel sort of thing that the sand falls on, and it tightens a spring.

after an hour, the spring releases energy to flip the hour glass over.

thoughts?

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4 hours ago, phillip1882 said:

this probably has been tried, use a hour glass with them separated in the middle,

use a water wheel sort of thing that the sand falls on, and it tightens a spring.

after an hour, the spring releases energy to flip the hour glass over.

thoughts?

The problem you will face is the mass of the sand is less than the mass of the hour glass. The energy stored in the spring may not actually flip the hour glass, but this is something you would actually have to try. The reason I think it wouldn't work is because you would have to move the mass of the sand and the hourglass which is more energy than the spring would gain by having the sand fall on it. See I have a hour glass sitting in my room near my computer and judging by the mass of the "casing" for the hour glass you couldn't flip it by having the sand fall on a spring. For my hour glass the mass is 9.95 oz or 0.282 kg and the mass of the sand is many times less than that probably around 1 oz or 0.0283495 kg. so just by doing the calculation of msandgh = E, we can calculate the energy stored in the sand is around 0.0686 Joules which is not nearly enough to flip a .282 kg hour glass which is 10 times the mass of the sand even if you wanted to move it at a 45 degree angle to flip it the Cosine of 45 degrees is .707 but you would have to move it a half a circle which is h * π , so it would require mhourglassghπ cos(45) = E , which is 1.5185982 Joules so you would need about 22.137 times more energy to flip it then the sand would produce by falling.

Edited by Vmedvil5
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I was going to reply with an answer similar to that posted by Vmedvil5, but he did such a good job, there is not much I can add.

The only thing I can add is all of these perpetual motion advocates never give their ideas much thought, and just run with them based on wishful thinking.

If they would only think these things through, in detail, and put away their wishful thinking, there would be a lot less of these posts.

But I suppose they do serve some purpose in making other people do their thinking for them.

Nice job, Vic! Thanks for helping to keep this place sane.

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ok thank you for correcting my idea. it seemed plausible to me this might work, but yeah i can't find fault with your calculations.

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On 9/16/2022 at 10:32 PM, Vmedvil5 said:

The problem you will face is the mass of the sand is less than the mass of the hour glass. The energy stored in the spring may not actually flip the hour glass, but this is something you would actually have to try. The reason I think it wouldn't work is because you would have to move the mass of the sand and the hourglass which is more energy than the spring would gain by having the sand fall on it. See I have a hour glass sitting in my room near my computer and judging by the mass of the "casing" for the hour glass you couldn't flip it by having the sand fall on a spring. For my hour glass the mass is 9.95 oz or 0.282 kg and the mass of the sand is many times less than that probably around 1 oz or 0.0283495 kg. so just by doing the calculation of msandgh = E, we can calculate the energy stored in the sand is around 0.0686 Joules which is not nearly enough to flip a .282 kg hour glass which is 10 times the mass of the sand even if you wanted to move it at a 45 degree angle to flip it the Cosine of 45 degrees is .707 but you would have to move it a half a circle which is h * π , so it would require mhourglassghπ cos(45) = E , which is 1.5185982 Joules so you would need about 22.137 times more energy to flip it then the sand would produce by falling.

All I gotta say to this..."like sands of an hour glass, so are the days of our lives". Soap opera drama lololol..

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