Speed of light circle

[Raider5678]

Hi guys, I was wondering how fast the end of a giant pole starting at the center of earth would be if it was "x" miles long. Now I decided to try ang get this pole to the speed of light. This is assuming earth spins once every 24 hours, and that this pole would be able to withstand the centrifugal force. So assuming that light travels at 670,616,629 mph. Which means the circumference of the circle that would be drawn by the end of this pole would have to be 16,094,799,096 miles around. Which means the length of the pole would have to be (2.56×10 to the power of 9) miles long starting at the center of the earth. And if it was this long, then the exact end of it would be traveling at the speed of light. Did I do math wrong here? Obviously we couldn't build something the long, it would reach mars, probably MUCH farther. But just as a thought experiment, is this correct? I included a diagram below. Every - is the pole.

 

 

 

Sun Mercury Venus Earth---Mars--------------Jupiter----------------Saturn------- Uranus

 

Freakin long pole.

Edited May 16, 2016 by Raider5678

[Endy0816]

That is what I got as well.

(c/(2*Pi)) * 24 hours

 

https://en.wikipedia.org/wiki/Orbital_speed#Mean_orbital_speed

Edited May 16, 2016 by Endy0816

[Strange]

Note that the end of the rod will never achieve that speed, however long it is.

 

This sounds a bit like the Ehrenfest paradox: https://en.wikipedia.org/wiki/Ehrenfest_paradox

[Raider5678]

Note that the end of the rod will never achieve that speed, however long it is.

 

This sounds a bit like the Ehrenfest paradox: https://en.wikipedia.org/wiki/Ehrenfest_paradox

Ok, I lost you there. From what I understand about the page is that the rods will contract or something? That or the speed will always change based upon the problem of the universal speed limit not allowing the end of the rod to get to that speed ..... Yeah, I'm lost.

[Delta1212]

Ok, I lost you there. From what I understand about the page is that the rods will contract or something? That or the speed will always change based upon the problem of the universal speed limit not allowing the end of the rod to get to that speed ..... Yeah, I'm lost.

The most important part is that there is no perfectly rigid material. As you get longer, the displacement from the rotation will propagate out at the speed of sound through the material which will cause it to bend and eventually break long before you reach what would be the speed of light at the far end.