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Q & A: rigid rods?

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Most recent answer: 04/26/2019
Q:
Theoretically if you had a solid iron rod that was stretched from one galaxy to an other and you moved that rod one foot would that rod move at the exact same time in the other galaxy even if was 10,000 thousand light years away?
- O.g. (age 63)
Van Buren arkansas
A:

No, it absolutely wouldn't happen that way. Nothing you do to one end of the rod can affect anything at distance L in time les than L/c, where c is the speed of light.

Does that mean the rod can't be rigid, no matter what it's made of? Yes. The forces between the parts of the rod are all fields that cannot travel faster than light. So the rod can't be rigid.

Mike W.


(published on 04/26/2019)

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