Escape the Frictionless Circle
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Re: Escape the Frictionless Circle
Is there gravity in this situation?
Re: Escape the Frictionless Circle
I wonder...
Spoiler:
"Please only print this post if you really need to"
...hmm....I wonder how much extra energy is required to generate that request...We need a cost/benefit analysis, STAT!
...hmm....I wonder how much extra energy is required to generate that request...We need a cost/benefit analysis, STAT!
Re: Escape the Frictionless Circle
Just because you're going very close to the speed of light, doesn't mean you can't still accelerate. You can't reach the speed of light, ever, period. There will always be more room to accelerate, from 0.99c to 0.999c to 0.9999c and so on.
I'm also not sure it's possible to start your "orbit" anyway. Since everything is frictionless except your interaction with the block, it gets hit by exactly the same force you do, moves directly away from you, then bounces back to meet you in the middle again. I don't think there's any way around that.
I'm also not sure it's possible to start your "orbit" anyway. Since everything is frictionless except your interaction with the block, it gets hit by exactly the same force you do, moves directly away from you, then bounces back to meet you in the middle again. I don't think there's any way around that.
The biggest number (63 quintillion googols in debt)
Re: Escape the Frictionless Circle
Here is my guess:
Jim
Spoiler:
Jim
Re: Escape the Frictionless Circle
@Jeff_UK: You cannot start such an orbit, unless you spin in the opposite direction very fast (or let the block spin). But it would not help, conservation of momentum (both linear and angular) is still exact in special relativity.
Re: Escape the Frictionless Circle
Talking about light speed, can you do anything with length contraction?
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Re: Escape the Frictionless Circle
Sort of a trick answer:
And an answer that quintopia already touched upon:
Spoiler:
And an answer that quintopia already touched upon:
Spoiler:
Re: Escape the Frictionless Circle
@jasondrake: That approach is so much easier:
Spoiler:
Re: Escape the Frictionless Circle
You can create angular momentum in various ways, like grabbing opposing corners of the cube and exerting force of them. Such processes can be repeated to make you and the block spin very very fast, and they whole no-friction etc. doesn't ever make you slow down. As you get closer to c relativistic effects will provide a solution, assuming you magically survive this.
Please be gracious in judging my english. (I am not a native speaker/writer.)
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Re: Escape the Frictionless Circle
Momentum is still perfectly conserved in special relativity.
Also, the block flies apart long before you reach relativistic velocities. Also, you fly apart long before the block does.
Also, the block flies apart long before you reach relativistic velocities. Also, you fly apart long before the block does.
Re: Escape the Frictionless Circle
Is flying apart not a kind of escaping the frictionless circle?
Apart from that. If you actually did spin at relativistic speed by length contraction the circle we are trapped on would have to shrink and maybe enable us to escape?
Apart from that. If you actually did spin at relativistic speed by length contraction the circle we are trapped on would have to shrink and maybe enable us to escape?
Please be gracious in judging my english. (I am not a native speaker/writer.)
http://decodedarfur.org/
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Re: Escape the Frictionless Circle
I had wondered if there could be some sort of trick regarding the COM of a spinning block/you system that could be manipulated by drawing the block closer to you (and you to the block, far more) at one part of the spin and then letting it out in another part of the spin, but:
a) The COM wouldn't change, that's the whole point,
b) How are we getting the spin, anyway, to uselessly exploit thus?
My final answer, though, to ruthlessly pinch from the solution to another (less impossible) problem of physics:
No?
a) The COM wouldn't change, that's the whole point,
b) How are we getting the spin, anyway, to uselessly exploit thus?
My final answer, though, to ruthlessly pinch from the solution to another (less impossible) problem of physics:
Spoiler:
No?
Re: Escape the Frictionless Circle
The important thing to me is that the rope connects you to the gold. So you can't throw a piece of gold, because any piece you break off will still be connected to you.
So here's a physics solution:
After a few octovigintillion years, you should make it to the edge with that plan.
But if you have a hot date you don't want to miss, here's a much faster solution, using logic instead of physics:
So here's a physics solution:
Spoiler:
After a few octovigintillion years, you should make it to the edge with that plan.
But if you have a hot date you don't want to miss, here's a much faster solution, using logic instead of physics:
Spoiler:
Re: Escape the Frictionless Circle
Well, I've only read through some solutions but...
Spoiler:
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Re: Escape the Frictionless Circle
But you're 100m from the edge, and I don't see how your scenario gets anything past that or how you move your center of gravity away from the center of the disc in the first place.
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Re: Escape the Frictionless Circle
LjSpike wrote:Well, I've only read through some solutions but...Spoiler:
This does give me an idea:
Spoiler:
Mikeski wrote:A "What If" update is never late. Nor is it early. It is posted precisely when it should be.
patzer's signature wrote:flicky1991 wrote:I'm being quoted too much!
he/him/his
Re: Escape the Frictionless Circle
Neil_Boekend wrote:LjSpike wrote:Well, I've only read through some solutions but...Spoiler:
This does give me an idea:Spoiler:
True. But with splitting the gold in half, you can use half to get back on your feet, and half to invest in a patent for this frictionless circle, (nobody has to know you didn't make it, and with how long you've been there, unless everyone is trapped in one, I don't think they'll question it).
I mean, it must have some real practical use, like aircraft bodies? Then you could pay a private investigator to find out who actually put you there in the first place.
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Re: Escape the Frictionless Circle
Solution:
Spoiler:
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Re: Escape the Frictionless Circle
Shufflepants wrote:Solution:Spoiler:
It probably saves a couple of million years if you're of above-average height.
Mikeski wrote:A "What If" update is never late. Nor is it early. It is posted precisely when it should be.
patzer's signature wrote:flicky1991 wrote:I'm being quoted too much!
he/him/his
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Re: Escape the Frictionless Circle
That the first answer that I've liked in this thread Shufflepants. Really nice work.
ameretrifle wrote:Magic space feudalism is therefore a viable idea.
Re: Escape the Frictionless Circle
First off, pushing won't work. Rolling won't work. Tipping won't work. Ignore the surface, it's utterly unhelpful. You, the block, and the rope are important.
Yes. Sliding anything on a frictionless surface would be infinitely easy. Simply grasp the weightless rope while fairly close to the block, and drag it around you in a circular motion by rotating your arm.
Obviously, you will begin sliding around in the opposite fashion, but with a frame of reference centered on you, it'll be pretty easy to get the large gold block orbiting you rapidly. Or, seen from the gold block's perspective, you're spinning around it, and also looking ridiculous. So, yeah, you can do that, it's just a matter of "and then what?"
You could use a length of the rope as a cutting edge, I guess. If it's effectively weightless and indestructible, that shit has to be impressive.
Alternatively, gold is more reflective than your average body. Nobody said it was a closed system. Sail your way out, utilizing the gold block as a sail.
tomandlu wrote:Is there any way you could get the gold block swinging around you, like someone warming up for a hammer throw, but with the block still in contact with the ground? Would/could that help?
Hmm... what if you wrapped the rope horizontally around the block and then pulled on it as though it was a yo-yo? What happens then? Would some of the energy be converted to rotational momentum, and would this help?
Yes. Sliding anything on a frictionless surface would be infinitely easy. Simply grasp the weightless rope while fairly close to the block, and drag it around you in a circular motion by rotating your arm.
Obviously, you will begin sliding around in the opposite fashion, but with a frame of reference centered on you, it'll be pretty easy to get the large gold block orbiting you rapidly. Or, seen from the gold block's perspective, you're spinning around it, and also looking ridiculous. So, yeah, you can do that, it's just a matter of "and then what?"
You could use a length of the rope as a cutting edge, I guess. If it's effectively weightless and indestructible, that shit has to be impressive.
Alternatively, gold is more reflective than your average body. Nobody said it was a closed system. Sail your way out, utilizing the gold block as a sail.
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Re: Escape the Frictionless Circle
Sorry for the bump but I wouldn't mind someone telling me what's wrong with this:
Edit: never mind
Spoiler:
Edit: never mind
Last edited by lordofthesnails on Mon Sep 05, 2016 2:06 pm UTC, edited 1 time in total.
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Re: Escape the Frictionless Circle
I have a problem with imparting (all-body) angular momentum.
Individual components can be given angular momentum of their own. e.g. sitting atop the mass, twisting yourself against that mass, you rotate one way, the mass rotates the other, but with sum-total angular momentum of you both being zero, without any way of leveraging against the static-but-frictionless arena beneath.
Same with turning the mass at (horizontal) arms-length/ropeglength/etc, any twist you apply is 'reflected' in a counter-spin dependant upon how you apply that spin but ultimately the 'barycentre' translates not and whole-system rotation is illusionary.
By wrapping round the rope (around yourself and/or the mass) you add localised rotation to one element and counterpart (counter-rotating) rotation to the other. Upon 'unwinding' the rope, you reverse this (faster or slower, but reverse the reverse too) and then you either go full-unravel and then 'reravel' until you hit the brakes or you slip the chord and (assuming the attachment allows zero torsion) merrily mutually oppositely spin to your heart's content forever, but the combined system still isn't spinning in totality.
I think.
Ultimately, there's no advantage, then, in any situation in which disconnection of any part of the system can be used. And if you can, then throwing chunks of block away (or the whole block) for LW near escape seems more useful than rotational escape...
Individual components can be given angular momentum of their own. e.g. sitting atop the mass, twisting yourself against that mass, you rotate one way, the mass rotates the other, but with sum-total angular momentum of you both being zero, without any way of leveraging against the static-but-frictionless arena beneath.
Same with turning the mass at (horizontal) arms-length/ropeglength/etc, any twist you apply is 'reflected' in a counter-spin dependant upon how you apply that spin but ultimately the 'barycentre' translates not and whole-system rotation is illusionary.
By wrapping round the rope (around yourself and/or the mass) you add localised rotation to one element and counterpart (counter-rotating) rotation to the other. Upon 'unwinding' the rope, you reverse this (faster or slower, but reverse the reverse too) and then you either go full-unravel and then 'reravel' until you hit the brakes or you slip the chord and (assuming the attachment allows zero torsion) merrily mutually oppositely spin to your heart's content forever, but the combined system still isn't spinning in totality.
I think.
Ultimately, there's no advantage, then, in any situation in which disconnection of any part of the system can be used. And if you can, then throwing chunks of block away (or the whole block) for LW near escape seems more useful than rotational escape...
Re: Escape the Frictionless Circle
A little bit of necromancy. I am pretty sure that my solution is overlooking something obvious and is thus wrong. However, physics was years ago and I don't understand what is wrong, so maybe someone can explain.
Spoiler:
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Re: Escape the Frictionless Circle
Unless I've misunderstood what you're saying, if you've converted unequal masses of initially zero relative (and absolute) momentum to inversely unequal velocities by an opposite-but-equal impulse at separation, then at the limit of the rope the unequal velocities get converted by the opposite opposite-but-equal impulse back to zero. Assuming inelasticity at the terminus. (If you get a spring-back, the lighter part again advances faster backwards, by suitable factors to cause them to rendezvous back at the centre.)
Is that it?
Is that it?
Re: Escape the Frictionless Circle
Initial thoughts are:
Push the block of gold away from you, but apply a spin to it.
Push the block of gold away from you, but apply a spin to it.
Spoiler:
Adacore wrote:In all honesty, BigNose has been pinging me slightly with almost every post since the start of the game. But he always does - I was utterly convinced he was anti-town for most of Wizardry2 and he was the High Wizard. I just can't read him.
Re: Escape the Frictionless Circle
I'm not sure I've completely followed all of that. But whatever you're trying to do, it blatantly breaks conservation of momentum so it can't work, sorry.
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Re: Escape the Frictionless Circle
Yeah, I think the issue is that you can't just negate your spin unless you pull on the rope hard enough to also stop the block from spinning.
Re: Escape the Frictionless Circle
More Info:
Spoiler:
Adacore wrote:In all honesty, BigNose has been pinging me slightly with almost every post since the start of the game. But he always does - I was utterly convinced he was anti-town for most of Wizardry2 and he was the High Wizard. I just can't read him.
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Re: Escape the Frictionless Circle
I misunderstood what you meant by negating spin, but as it turns out spin isn't relevant to why it can't work anyway.
If the gold block does something to pull in the rope, or if you do something to pull in the rope, a tension is applied to the rope and it pulls on both you and the block equally. There's no way to get around that basic Newtonian fact of the matter.
If the gold block does something to pull in the rope, or if you do something to pull in the rope, a tension is applied to the rope and it pulls on both you and the block equally. There's no way to get around that basic Newtonian fact of the matter.
Re: Escape the Frictionless Circle
Working the gold block by hand into a 100 meter wire is still my favored solution. Pretty sure this would be possible, but I don't have 8 kg of gold to try it with.
The biggest number (63 quintillion googols in debt)
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Re: Escape the Frictionless Circle
Or someone with easy access to gold.
And egress, easy or otherwise. Just make sure to check with 'em if it's been laundered first!
And egress, easy or otherwise. Just make sure to check with 'em if it's been laundered first!
Re: Escape the Frictionless Circle
BigNose wrote:More Info:Spoiler:
In addition to what gmalivuk said (which is the bottom line) you seem to be treating angular momentum (spinning) and linear momentum (sliding) as interchangeable, so that one can be traded off to gain the other.
They're not and you can't - each of them has to be conserved separately. You can manipulate the spins of yourself and the block to send both of you orbiting round the common centre of mass (which is what your scenario will probably achieve) but you can't use them to *move* the centre of mass.
Re: Escape the Frictionless Circle
Any solution to the problem presented here would also work as a reactionless space drive.
Re: Escape the Frictionless Circle
Spoiler:
Re: Escape the Frictionless Circle
The OP doesn't state but the general assumption seems to be that the circle is on the surface of a planet, possibly a perfectly uniform sphere of uniform density.
Spoiler:
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Re: Escape the Frictionless Circle
speising wrote:Any solution to the problem presented here would also work as a reactionless space drive.
Except the ones that rely on momentum input from or output to outside the system (i.e. from photons) or that involve stretching something (like the rope or the gold) so it reaches beyond the frictionless area.
Re: Escape the Frictionless Circle
More:
PS
tl;dr If A + B = C + D, but A is negated, then B <> C + D, ergo you are pulled.
Spoiler:
Spoiler:
tl;dr If A + B = C + D, but A is negated, then B <> C + D, ergo you are pulled.
Adacore wrote:In all honesty, BigNose has been pinging me slightly with almost every post since the start of the game. But he always does - I was utterly convinced he was anti-town for most of Wizardry2 and he was the High Wizard. I just can't read him.
Re: Escape the Frictionless Circle
gmalivuk wrote:speising wrote:Any solution to the problem presented here would also work as a reactionless space drive.
Except the ones that rely on momentum input from or output to outside the system (i.e. from photons) or that involve stretching something (like the rope or the gold) so it reaches beyond the frictionless area.
The first of those violates the premise (only forces excerpted by your limbs), the second seems somewhat cheating to me. (rule lawyering)
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