The ISS travels at a constant speed in relation to the earth. People have to get on and off a train
Comment on The Hyperloop was always a scam
blazera@kbin.social 10 months agoRight, that was the whole point. I think folks arent appreciating air resistance. The ISS is an example of what vehicles are capable of without it. Speeds incomparable to anything on earth, with little fuel usage. Its the largest source of inefficiency in travel. And the engineering science of reducing it is wholesale a scam for people.
michaelmrose@lemmy.world 10 months ago
blazera@kbin.social 10 months ago
Yes, acceleration is a thing, but trains a)reach a top speed and spend a lot of fuel maintaining it, and b)reaches much, much lower top speeds, with any effort to increase it requiring exponentially more fuel to reach and maintain. Air resistance is an absurdly important factor to travel efficiency.
HaywardT@lemmy.sdf.org 10 months ago
I think a better example is airplanes. You run at high altitudes to increase efficiency due to reduced atmosphere.
thorbot@lemmy.world 10 months ago
Whoooosh
misophist@lemmy.world 10 months ago
No, without air resistance , you don’t get that sound.
blazera@kbin.social 10 months ago
Yeah i seen the rest of it, i was short on time. Thats not how engineering tubes works, we use them because you can add as much length as you want, the balancing of pressure forces occurs cross sectionally. A 2 foot pipe carrying 100 psi is experiencing the same stresses as a 2 mile pipe at 100 psi. You might as well be adding a /s to the idea of distributing water through pipes.
prime_number_314159@lemmy.world 10 months ago
Very long pipes use expansion/contraction sections that may not be possible for a vacuum sealed system that has to be incredibly straight to allow the passage of a train, and can flex pretty significantly for earthquakes, seasonal temperature changes, etc.
blazera@kbin.social 10 months ago
Earthquakes keep getting brought up as if they're not devastating to absolutely everything we already use. What if an earthquake hits a regular train? Or a bridge, or a house. only a vacuum tube is susceptible to earthquakes.
HaywardT@lemmy.sdf.org 10 months ago
You deal with thermal expansion the same way you do with continuous welded rail.