# As a matter of discussion

1. Jul 18, 2008

### liongoth

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...

2. Jul 18, 2008

### gendou2

Yes it does, since it has to travel a circle of larger diameter in the same amount of time.

3. Jul 18, 2008

### Staff: Mentor

I'd say just the opposite.

4. Jul 19, 2008

### robertm

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...

5. Jul 20, 2008

### aniketp

I think the string that is away moves faster. The radius is more but the angular velocity remains the same.

6. Jul 22, 2008

### liongoth

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

7. Jul 22, 2008

### Kurdt

Staff Emeritus
See Doc Al's post.

8. Jul 22, 2008

### liongoth

What's the name of it, or a link for it?

9. Jul 23, 2008

### robertm

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?

10. Jul 23, 2008

### liongoth

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....

11. Jul 23, 2008

### octelcogopod

Heh, no.

12. Jul 23, 2008

### cristo

Staff Emeritus
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.