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Comment Re:Tunnel (Score 1) 135

When discussing a vacuum container at sea level the pressure on the container will be one atmosphere which is 101kPa or 15psi and not equivalent to 10 meters of water.

The pressure differential between a container of perfect vacuum and ambient atmosphere at sea level is about 14.7 psi. The pressure differential between a container of air at one atmosphere and ambient seawater at 10m depth is about 14.7 psi. Each 10m of seawater depth increases ambient pressure by approximately one atmosphere. At 100m, pressure is 10 atmospheres higher than the surface. Freshwater is less dense than seawater, so pressure increases a bit more slowly.

Any SCUBA diver knows this.

Here's a calculator if you'd like to play with it.

Comment Re:Illegals are illegal (Score 1) 284

Does it apply only to immigrants, or is anybody who breaks the law an "illegal"?

How specious of you. Burglars, etc, are indeed "illegal" and if caught are punished by law. It's only being asked that those breaking the immigration law be punished as well.

We have an economy that cannot function without more immigrant labor than our immigration laws allow.


Comment Re:Yeah (Score 5, Informative) 136

Also notice how the charges are rarely direct, mostly its a grand jury who decides and the DA can influence how its run.

Note that DC is under federal jurisdiction, so all terms of the fifth amendment apply. This means that in DC prosecution of any "infamous crime" (i.e. felony) requires indictment by a grand jury, per the opening text of the 5th, which reads "No person shall be held to answer for a capital, or otherwise infamous crime, unless on a presentment or indictment of a Grand Jury".

Since the grand jury clause has not been incorporated into the 14th amendment against the states, states are not required to follow this process. Many do, but not all.

Comment Re:A Terrorist's Wet Dream (Score 2) 135

29 minutes huh? So does that mean passengers get 10 minutes to board/deboard this thing????? It's gonna have to be quickly loaded. Leaving 9 minutes of travel time?

The pods are small. Think subway car-sized, not jumbo jet sized. How long does the subway stop at each location? Two minutes? Pods are expected to have a maximum speed of 760 mph, which would cover 226 miles in 18 minutes.

And how are passengers going to react to the acceleration/deceleration necessary

Well, at 1/4 gee acceleration (8 f/s^2), you'd need 139 seconds to accelerate to 760 mph. For the described journey, you'd have to accelerate or decelerate 6 times, so that would take 14 minutes, leaving 11 minutes at top speed. During each acceleration or deceleration, you'd cover 14.7 miles, so the six accel/decel periods would cover 88 miles. At 760 mph for 11 minutes, you'd cover 139 miles, that adds up to 227 miles.

So, 1/4 gee acceleration is sufficient, and while what's about 3X the acceleration of a subway car, it's very tolerable. It might actually be more comfortable to do 1/2 gee for 66 seconds, or 1 gee for 34 seconds, on the theory that it's better to spend less time accelerating harder, to have more time at constant velocity.

Tell me oh /. Masters of the Universe where I am wrong?

In your initial assumption that loading and unloading a hyperloop car is like loading and unloading an airplane. Are there any other easy problems you'd like solved?

Comment Re:Tunnel (Score 3, Insightful) 135

Well, I don't think it would be acceptable to say that the passengers will be fine unless there's a huge rupture and they're right next to it, in which case everyone could be killed.

Making a huge rupture in a 1" thick steel tube will require a large quantity of explosives. Such a quantity of explosives won't harm a bus full of passengers unless they're right next to it, in which case everyone could be killed. We don't take that as an argument for eliminating buses.

putting it underground seems to solve a bunch of other problems too.

At the expense of creating a bunch of other ones. Engineering is all about tradeoffs. Boring will make sense primarily in densely-populated areas. Elsewhere, the original elevated tube design will be better, I think.

Comment Re:How does Google get this? (Score 2) 90

Remember that Google also performs a security check of every web address to make sure it is not a malware site.

Only if you agreed to turn that on.

It's actually a really good idea from a security perspective, assuming you're comfortable with Google receiving that information. I am... but then I browse logged in to a Google account, and have Web History turned on. I find it very useful to be able to search and review my own browsing history. YMMV, and you have to make the privacy vs security/convenience tradeoff yourself. The controls are there to allow you to do it.

Comment Re:How does Google get this? (Score 1) 90

Is anyone else vaguely perturbed that we are getting information on this increase in a privacy-enhancing technology by Chrome apparently watching every website that a wide variety of users go to and sending that information back to Google?

In Chrome, go into Settings. Click "Advanced", then look under "Privacy" for "Automatically send usage statistics and crash reports to Google". If that is enabled, it's because you approved it. If it's disabled, Chrome is not sending the information.

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