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A googol-to-one gear ratio [video]

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Re: A googol-to-one gear ratio [video]

#31

Post by Benjammer »

noncoml wrote: post #27
Benjammer wrote: post #10

The original mentioned, Arthur Ganson's Machine with Concrete, is quite a bit more artistic. The end is cast in concrete. The idea is that there is a certain amount of energy lost as friction in each gear, per turn. If you calculate the gear ratios and how many turns of the earlier gears would be required to make the final gear move, even infinitesimally, the amount of energy lost becomes more than all the energy in…

Impressive but imho he could take it one step further and instead of concrete on the other end, he could rotate the gear in the opposite way.

It would take more energy than the total energy of the known universe to turn the last gear.

Re: A googol-to-one gear ratio [video]

#32

Post by jagged-chisel »

chrisseaton wrote: post #24
tunesmith wrote: post #20

Earlier quoted context omitted.

Yeah, but that's just an engineering problem.

> that's just an engineering problem It's not - it's a physics problem - it reaches fundamental physical limits of the universe.

Like he said, an engineering problem.

Re: A googol-to-one gear ratio [video]

#34

Post by NegativeLatency »

jagged-chisel wrote: post #30
noncoml wrote: post #27

Earlier quoted context omitted.

Impressive but imho he could take it one step further and instead of concrete on the other end, he could rotate the gear in the opposite way.

When all the slack has been rotated out, it would require a tremendous amount of force to rotate that last gear in reverse. After all, the system wants to amplify the gear speed from that end.

I think parent’s idea would work if the system was mirrored and duplicated. Then you could attach the two the them together with the stationary gears in the middle

Re: A googol-to-one gear ratio [video]

#35

Post by owenmarshall »

chrisseaton wrote: post #4
Thorentis wrote: post #3

Why can't it spin faster?

I'm sure it can spin a bit faster. Why can't it spin so fast that the final wheel visibly turns? Well the first wheels would melt from friction or be torn apart before then, and where are you going to get that much energy to turn them so fast? At some point there's the speed of light as a limit as well.

There are 10^80 electrons in the universe, Eddington thinks.

Even if you managed to make a contraption that turned one electron into one rotation of the first wheel, and you fed the entire universe to your contraption... you’re coming up a few dozens order of magnitude short to make that full turn :^)

Re: A googol-to-one gear ratio [video]

#37

Post by rtkwe »

NegativeLatency wrote: post #34
jagged-chisel wrote: post #30

Earlier quoted context omitted.

When all the slack has been rotated out, it would require a tremendous amount of force to rotate that last gear in reverse. After all, the system wants to amplify the gear speed from that end.

I think parent’s idea would work if the system was mirrored and duplicated. Then you could attach the two the them together with the stationary gears in the middle

So 10^100:1:10^100? I think the slack, friction losses, flex, material strength would all take out so much of the energy you'd get a tiny fraction of movement at the far end if any.

Re: A googol-to-one gear ratio [video]

#38

Post by chrisseaton »

owenmarshall wrote: post #35
chrisseaton wrote: post #4

Earlier quoted context omitted.

I'm sure it can spin a bit faster. Why can't it spin so fast that the final wheel visibly turns? Well the first wheels would melt from friction or be torn apart before then, and where are you going to get that much energy to turn them so fast? At some point there's the speed of light as a limit as well.

There are 10^80 electrons in the universe, Eddington thinks. Even if you managed to make a contraption that turned one electron into one rotation of the first wheel, and you fed the entire universe to your contraption... you’re coming up a few dozens order of magnitude short to make that full turn :^)

That's what I already said

> where are you going to get that much energy to turn them so fast?

Re: A googol-to-one gear ratio [video]

#39

Post by kibwen »

nostrademons wrote: post #19
_underfl0w_ wrote: post #8

Part of me likes to thing something crazy would happen if you turned it from the other end. Turn one gear once and the gear at the far other end turns a googol times but melts somewhere around a trillion rotations. Almost doesn't feel too outlandish given a scope that already includes "more energy than the entire known universe has" (per the article) for a measurement.

You would need a tremendous amount of torque to move the last gear, because gears multiply the angular velocity on one side and multiply the torque on the other. If it took one newton-meter (about the weight of one apple on a lever a meter away from the gear) to move the first gear, it would take a googol newton-meters applied at the other end of the device.

> one newton-meter (about the weight of one apple on a lever a meter away

Aside, but I'm delighted to learn that one Newton is approximately one apple's worth of force. :)

Re: A googol-to-one gear ratio [video]

#40

Post by Benjammer »

NegativeLatency wrote: post #34
jagged-chisel wrote: post #30

Earlier quoted context omitted.

When all the slack has been rotated out, it would require a tremendous amount of force to rotate that last gear in reverse. After all, the system wants to amplify the gear speed from that end.

I think parent’s idea would work if the system was mirrored and duplicated. Then you could attach the two the them together with the stationary gears in the middle

Wow I like this idea, instead of concrete you really emphasize the point with another motor the opposite direction and the other end.
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