3 ms·
I agree it's impractical, but I believe you're double counting the force on the cable. Each end of the cable pulls with 1.3 MN, which means that the cable itsel
by hexane360 5y ago
I agree it's impractical, but I believe you're double counting the force on the cable. Each end of the cable pulls with 1.3 MN, which means that the cable itself can be in static equilibrium (in the rotating frame of reference). The same is true if you hang a 1.3 MN space station from the ceiling. The space station pulls down with a force of 1.3 MN, while the ceiling pulls up with a force of 1.3 MN.
- kamray23 5y agoThat's probably a reasonable conclusion. It does happen to be totally overshadowed by my bigger mistake, which is an order of magnitude. Repeating the calculations using my physics CAS today: Starship mass: 1.3·10³ kg Starship weight: 1.3·10⁷ Newtons Converting that into something reasonable, it's 13 MN, not 1.3. A Kevlar fibre cable will be 22 tonnes, a PE one 9000 tonnes, and a carbon one 2200 tonnes. I wouldn't like to even imagine steel. And these are just with a breaking strength of 13 MN. Not the most reasonable, though obviously we've held up things like Arecibo in the past. Using multiple smaller cables would be the optimal solution and what we would go with, since a single cable is >1 meter in diameter in any case. The mass doesn't get any smaller like that, though, so it's not a consideration we'd need to make.