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Author Topic: Does speed increase force?  (Read 3397 times)

LetoII

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Does speed increase force?
« on: 18/03/2013 16:14:24 »
if you were to spin a ball inside a circular tube at some point the tube would brake due to the momentum the ball gains which pushed on the inside of the tube.

now here's where my question comes in.
would the circular tube break at a later point in time if it were traveling through space really fast?
in other words, does the strenght of the tube increase if i speed it up. much like certain particles will decay slower when traveling at great speeds.

thanks and sorry for my lack of better words.
« Last Edit: 24/03/2013 23:20:50 by chris »

JP

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Re: does speed increase the strenght of everything?
« Reply #1 on: 18/03/2013 16:45:33 »
No, speed and strength aren't really related.

What is important to know is that objects in motion like to move along straight lines and it takes force to change their direction.  The faster the direction is changed, the more force is required.  A ball moving around a tube is not moving in a straight line, and the reason for that is that as it rolls forward the tube exerts a force that pushes it radially inward.  As the ball rolls faster, more force is required to keep pushing it inward, until at some point, that force exceeds the strength of whatever material is making up the tube and the ball breaks through it and continues off in a straight line.

If you rotate the tube, each piece of the tube is now moving, and not in a straight line.  So the tube has to exert forces to keep all the pieces moving in a circle.  If these required forces become larger than the tube can exert, it will fly apart and all the pieces will fly off in straight lines.

So if you rotate the tube and send a ball around inside of it, I'd expect it to break sooner, since the tube has to keep the ball moving in a circle and keep its own pieces moving in a circle.

imatfaal

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Re: does speed increase the strenght of everything?
« Reply #2 on: 18/03/2013 17:05:46 »
Leto - if you are travelling with the tube then you would notice no change, there is no length contraction, no time dilation etc.  And whilst observers will get different timings for events (that they could reconcile with a bit of maths if they know their relative speeds) observers all agree on what actually happened - ie the tube does not stay whole for one observer and split for another (and as JP said - it wouldn't be effected any way)

The reason we use muon decay to show time dilation is that we, the observers in the frame of earth, see the particle travel 50km of atmosphere (in a period of which time they should decay) but we believe they reach the ground because their clocks have been running slow compared to ours.  They, the muons, have clocks that must run at normal speed because no clocks are altered within one single frame; but the muons "see" the earth and its atmosphere rushing up towards them at relativistic speeds, thus the height of the atmosphere is contracted from the frame of the muon and they can cross that contracted space in even their short normal life spans

simplified

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Re: does speed increase the strenght of everything?
« Reply #3 on: 19/03/2013 13:54:39 »
thus the height of the atmosphere is contracted from the frame of the muon and they can cross that contracted space in even their short normal life spans
Contracted distance should increase gravitational interacting,but that doesn't increase due to length contraction.
« Last Edit: 19/03/2013 16:00:07 by simplified »

imatfaal

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Re: does speed increase the strenght of everything?
« Reply #4 on: 19/03/2013 16:24:12 »
thus the height of the atmosphere is contracted from the frame of the muon and they can cross that contracted space in even their short normal life spans
Contracted distance should increase gravitational interacting,but that doesn't increase due to length contraction.

Once you talk about gravity you have to consider curved space - and SR specifically deals in flat space.  Once you have relativistic speeds I am not sure how well newtonian gravity functions as an approximation - maybe Pete or JP could shed some light

yor_on

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Re: does speed increase the strenght of everything?
« Reply #5 on: 20/03/2013 11:18:33 »
Not if it is a preferred direction Simplified. We are the ones defining it as a 'force', well some do, not all. But if it just is a observer dependent 'path' (as described by us measuring lights 'propagating', or muon's) then those definitions will be found lacking.
==

Remember that you locally can transform away any gravity, by any geodesic, no matter what 'speed' you define to it.
« Last Edit: 20/03/2013 22:32:05 by yor_on »

simplified

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Re: does speed increase the strenght of everything?
« Reply #6 on: 20/03/2013 17:49:15 »
Not if it is a preferred direction Simplified. We are that ones defining it as a 'force', well some do, not all. But if it just is a observer dependent 'path' (as described by us measuring lights 'propagating', or muon's) then those definitions will be found lacking.
==

Remember that you locally can transform away any gravity, by any geodesic, no matter what 'speed' you define to it.
In our system we can define changing of  energy of  traveling muon due to gravitational interaction(or due to geodesic). Terrestrial motionless muon should have  the same energy for traveling muon. Isn't it? How does traveling muon predict the same,using own contracted distance?

yor_on

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Re: does speed increase the strenght of everything?
« Reply #7 on: 20/03/2013 22:35:02 »
Simplified, there are two things I wrote, one is the question if 'gravity' should be considered a 'force'. Which I don't agree on. The other was your question, which is answered by how all geodesics actually transform away the 'gravity'. There can't be a gravity in a geodesic, it's the equivalence to a free fall, in space. No 'gravity' to be noticed locally.
=

and my spelling needs some polish :)
« Last Edit: 20/03/2013 22:49:48 by yor_on »

simplified

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Re: does speed increase the strenght of everything?
« Reply #8 on: 23/03/2013 06:59:17 »
Simplified, there are two things I wrote, one is the question if 'gravity' should be considered a 'force'. Which I don't agree on. The other was your question, which is answered by how all geodesics actually transform away the 'gravity'. There can't be a gravity in a geodesic, it's the equivalence to a free fall, in space. No 'gravity' to be noticed locally.
=

and my spelling needs some polish :)
Nano-inhabitants of traveling muon can't predict change of energy of terrestrial muon without definition of distance between own muon and center of Earth.Should they use own coordinates or coordinates of motionless observer relatively of Earth?

yor_on

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Re: Does speed increase force?
« Reply #9 on: 26/03/2013 00:14:30 »

remember that those are my own. My definition is that the only way you ever will make a sense of the universe is from your experiments. And the only way you can do those is locally.

If you know a better way, I'm your man :)

What I do is philosophy from those assumptions. Although I draw some conclusions defining it from a small scale. I'm not sure on what makes a universe, and I'm not sure on our definitions of 'motion', 'potential energy' and a 'common universe', but a lot of my questions also comes from my view of that the universe should be understandable.

So we need to change our outlooks.
and that's what you're trying for too, right?

Nothing wrong in that,

Pmb

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Re: Does speed increase force?
« Reply #10 on: 27/03/2013 21:51:35 »
No, speed and strength aren't really related.
Note: There is one exception to this rule. The force on a charged particle moving through a magnetic field is proportional to the speed of the particle and the componet of the magetic field perpendicur to the trajectory of the particle.

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Re: Does speed increase force?
« Reply #10 on: 27/03/2013 21:51:35 »