what really fucks me up is combining this with relativistic effects
like what if you had a rod 100,000 km long and you started rotating it around one end. does the other end exceed the speed of light? I know the answer has to be no, which means you're going to get all sorts of weird relativistic effects along the rod
I have heard this thought experiment before. I think the answer is that there is no perfectly rigid rod. The nudge at one end travels down the rod as a pressure wave at the speed of sound of the material, which will be much slower than the speed of light. And in reality, centripetal force would tear apart a rod well before its tips rotate at light speed.
what really fucks me up is combining this with relativistic effects
like what if you had a rod 100,000 km long and you started rotating it around one end. does the other end exceed the speed of light? I know the answer has to be no, which means you're going to get all sorts of weird relativistic effects along the rod
I have heard this thought experiment before. I think the answer is that there is no perfectly rigid rod. The nudge at one end travels down the rod as a pressure wave at the speed of sound of the material, which will be much slower than the speed of light. And in reality, centripetal force would tear apart a rod well before its tips rotate at light speed.
The force required to accelerate the outer part above light speed exceeds infinity
give me a lever big enough and i will turn the world
If you put clocks on different parts of the rod, they'd get out of sync. It's weird.