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A googol-to-one gear ratio [video]

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

#81

Post by tuco86 »

peteradio wrote: post #53
warent wrote: post #13

Earlier quoted context omitted.

All this time we've been fussing about clean energy and perpetual motion machines when all we needed was this machine to apply essentially infinite leverage and generate a universe of energy at the flick of the wrist

Woops accidentally solved fermi's paradox and the mystery of what created the big bang, in one shot.

At first there was God. Then Adam and Eve. Then one of their descendants built this machine and prayed for god to turn the last wheel. Bang! (a big one)

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

#82

Post by aj7 »

autonoshitbox wrote: post #74
aj7 wrote: post #7

I bet the zero point fluctuation motion of the last gear dwarfs the deterministic motion.

The word you're looking for is "thermal." The bulk of the gear behaves completely classically at this temperature.

I think you are right in the sense that at room temperature, thermal fluctuations dominate.

Better stated, my point is that if the entire assembly is at absolute zero, the quantum fluctuations in the final gear are much greater than the deterministic motion associated with one revolution of the first gear.

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

#83

Post by iamaelephant »

kibwen wrote: post #39
nostrademons wrote: post #19

Earlier quoted context omitted.

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. :)

Maybe if you have a very big apple. 1 nM is the force of 1 Newton (1kg on Earth) at 1 meter.

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

#84

Post by ehsankia »

lacker wrote: post #11

If every electron in the universe came over and cranked that first gear around a hundred times, it still wouldn't be enough to make the last gear visibly move.

Stupid question, but realistically what would happen if you tried to manually turn that last gear? Would nothing move? What if you put a lot of force, what would happened / which part would break?

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

#86

Post by profmonocle »

I would love for someone who knows more about physics to explain what effect a single rotation of the front gear actually has on the last one.

Naively you would assume that every rotation of the first gear rotates the last by one googolth. But (I assume) that can't be true in the real world, since that distance is significantly smaller than a planck length.

I have some educated guesses as to how the rotation is actually being "stored" if it's not physically moving the final gear, but I'm probably more ignorant than I think - for example I'm not totally sure I understand what a "planck length" is.

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

#88

Post by devenson »

iamaelephant wrote: post #83
kibwen wrote: post #39

Earlier quoted context omitted.

> 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. :)

Maybe if you have a very big apple. 1 nM is the force of 1 Newton (1kg on Earth) at 1 meter.

you forgot g, 1kg weighs 9.8 newtons on Earth.

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

#89

Post by inimino »

ehsankia wrote: post #84
lacker wrote: post #11

If every electron in the universe came over and cranked that first gear around a hundred times, it still wouldn't be enough to make the last gear visibly move.

Stupid question, but realistically what would happen if you tried to manually turn that last gear? Would nothing move? What if you put a lot of force, what would happened / which part would break?

An interesting question!

As a guess, there should be some slack and elasticity in the last two gears or so, which you could get out if you used enough force. Beyond that, the effective torque is reduced by 100x or 1000x already, which means moving any further gear even by the width of an atom would probably require more torque than the final gear can bear, and either the teeth or some other weak point would fail on the last gear. Of course, even what motion there is (up to failure) would be hard to observe. Moreover, putting this much torque on the end of the structure would also likely torque the entire machine end to end (like twisting a rope) and generally mess things up in uninteresting ways.

Putting all that together, I think an observer would probably say nothing is moving, right until the last gear and/or entire structure fails spectacularly.

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

#90

Post by praptak »

iamaelephant wrote: post #83
kibwen wrote: post #39

Earlier quoted context omitted.

> 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. :)

Maybe if you have a very big apple. 1 nM is the force of 1 Newton (1kg on Earth) at 1 meter.

Newton is 0.1 kg on Earth. (Approximately)
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