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liongoth
Jul18-08, 04:20 PM
I wonder, if you tie a string to a stone and spin it around, does the string that is closer to your hand move faster than the string that is tied to the stone?

*EDIT* This question leads to a much greater topic of discussion, and the reason for leading off with this question is because the rest of the question is contingent upon this concept...

gendou2
Jul18-08, 04:57 PM
Yes it does, since it has to travel a circle of larger diameter in the same amount of time.

Doc Al
Jul18-08, 05:14 PM
I wonder, if you tie a string to a stone and spin it around, does the string that is closer to your hand move faster than the string that is tied to the stone?
I'd say just the opposite.

robertm
Jul19-08, 11:54 PM
I wonder, if you tie a string to a stone and spin it around, does the string that is closer to your hand move faster than the string that is tied to the stone?

*EDIT* This question leads to a much greater topic of discussion, and the reason for leading off with this question is because the rest of the question is contingent upon this concept...

Hi and welcome to PF liongoth,

What kind of discussion are you fishing for here? The philosophical implications of basic rotational mechanics? I do not see your motive/s...

aniketp
Jul20-08, 12:53 AM
I think the string that is away moves faster. The radius is more but the angular velocity remains the same.

liongoth
Jul22-08, 08:49 AM
Yes it does, since it has to travel a circle of larger diameter in the same amount of time.

Aha, then if this is true, then what if the stone is moving at the speed of light?

Kurdt
Jul22-08, 08:53 AM
See Doc Al's post.

liongoth
Jul22-08, 11:55 PM
See Doc Al's post.
What's the name of it, or a link for it?

robertm
Jul23-08, 12:14 AM
What's the name of it, or a link for it?

No, no, he means the earlier post made by Doc Al.

There is a basic mathematical relation to the angular speed of a given point on the string, and the length of the arc traced by that point. A point on the string closer to your hand would not have a higher Angular speed than the point at the rock. Not the other way around.

Check this page out for a basic tutorial on rotational mechanics: http://www.sparknotes.com/testprep/books/sat2/physics/chapter10.rhtml
That should clear it up for you.

So, was there a philosophical question that you had?

liongoth
Jul23-08, 12:21 AM
Well, it was a matter of what really occurs when you observe the string, you see the string move so fast it goes backwards, and the thought had occured to me that maybe we can move so fast that time will flow backwards, that is, if we could move faster than the speed of light....

octelcogopod
Jul23-08, 06:11 AM
Well, it was a matter of what really occurs when you observe the string, you see the string move so fast it goes backwards, and the thought had occured to me that maybe we can move so fast that time will flow backwards, that is, if we could move faster than the speed of light....

Heh, no.

cristo
Jul23-08, 06:28 AM
Well, it was a matter of what really occurs when you observe the string, you see the string move so fast it goes backwards, and the thought had occured to me that maybe we can move so fast that time will flow backwards, that is, if we could move faster than the speed of light....

Nonsensical comments are not permitted at PF, even in the Philosophy forum. If you have a genuine question on the physics, then please post it in the relativity forum, otherwise, refrain from making the speculative posts in future.