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What is the theoretically fastest way that you could get from LA to San Francisco?
It can never crash.
It’s immune to weather.
The hyperloop, you know, is something that would go effectively faster than the speed of sounds.
Elon Musk has been talking about hyperloop for a while in the vaguest possible terms
until now because he has released a 57-page document outlining his plans.
If you’re not familiar with Musk, he’s been involved or come up with paypal,
Testla electronic cars, the Space X program which came up with the world’s first reusable rockets
and designed the Falcon rocket system for NASA.
He’s invested heavily in solar energy.
Basically, he’s had more great ideas than I have had.
And his plans for Hyperloop would involve linking 2 urban areas,
probably no more than 1,500 kilometers apart,
with a low-pressure pneumatic tube-type system,
sending pods carrying people from town to town at close to sonic velocity.
Now, he’s proposals are to build a cheap network from Los Angeles to San Francisco.
Because going much farther than that, he says it would become economically unviable.
It will be cheaper to go by a Supersonic plane.
Now if you’ll just have a tube, full of air with pods travelling through it, that wouldn’t be quick.
The friction would make the source of speeds he’s talking about is impossible.
There have been similar plans released previously by Rand Corporation and ET3.
That would be even quicker than these ones using electromagnetic suspension in a total vacuum.
But the problem there is leaks.
One seal or small crack on a huge tube network would stop it working.
But Musk has a solution to that which is a low pressure system instead of a total vacuum,
that could cope with small leaks but would introduce another problem –
the Kantrowitz Limit
In basic terms, if the walls of the tube and the capsule are too close together,
the capsule begins pushing the air in the system instead of letting it flow past.
A bit like a pressure build-up in a syringe.
So the Kantrowitz Limit means that you have to either travel very very slowly
or build a tube with a huge diameter in which case you can travel quicker
but you subject yourself to crushing g force as soon as you get round the slightest bend.
But again Musk has a solution which is to put a battery powered electric compressor fan
at the front of the pod pumping air to back and relieving pressure.
He reckons that would work when combined with an external linear electric motor.
That’s the same sort of one that you’d get in an electric car but flattened.
And that would accelerate the pods up to full speed and give them a power boost every now and then.
So all of this is gotta be ridiculously expensive, right?
Well, Elon Musk reckons that he can build this for several billions dollars which sounds like a lot
but he says that it’s still cheaper than the proposed high speed rail network in California.
So his proposal would be to build an elevated tube network on pylons alongside an existing highway.
And that would provide a straight line, relatively few land disputes and be able to be built in prefabricated sections.
And on top of all of that, he says his plans would be more resistant to earthquakes and thermal expansion and contraction than a traditional railway.
So it sounds perfect but obviously, there were skeptics.
As I’ve seen for this seemed really low for me for a system that requires rights of way through major metropolitan regions which this one does.
Even when you build an elevated… say an elevated train which we do all the time in transportation,
There are substantial costs to that in terms of right of way acquisition
and there will always environmental lawsuits challenging your ability to try to construct such rights of way.
Because people don’t necessarily want new elevated things whizzing by their houses.
So there were doubts as to whether or not this can actually happen.
But if Elon Musk plans can become a reality, there will be faster, cheaper, more environmentally friendly,
more earthquake resistant, more weather proof, and less disruptive than current modes of transport.
So, I for one hope that I can travel on this within the next few years.
I’d also like to see him build me a hoverboard.
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Hyperloop - ultra high-speed public transport unveiled by Elon Musk - Truthloader

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Go Tutor 2014 年 3 月 5 日 に公開

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