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Comment Re: So, how often does it explode? (Score 1) 230

The word 'explosion' literally implies something that grows bigger

The electric arc heats the air around it into a plasma. That plasma expands rapidly, resulting in an explosion.

It takes a MASSIVE explosion for the shockware to actually injure people.

Injuries like ruptured eardrums and collapsed lungs...

But that rapid-expansion bit means explosions have shrapnel, and that is the much bigger risk. Most people who die in explosions are killed by shrapnel. An arc-flash doesn't have shrapnel.

Well the explosion tends to blow apart whatever equipment just failed, producing shrapnel. Seriously, did you even watch the video?

Comment Re: So, how often does it explode? (Score 1) 230

From the video...

It creates a pressure wave, called an arc blast, that can reach thousands of pounds per square inch. Enough to knock someone off a ladder, rupture an ear drum, or collapse a lung.

That sure sounds like an explosion to me, far more violent than rather slow conflagration you see from the runaway chemical reaction in a li-ion cell. You did see it blow the head off that mannequin, didn't you?

Comment Re:Cognitive Load (Score 1) 210

Client-side hashing only protects the password if the content server itself has been fully compromised, in which case none of it matters, because the server is compromised and they have full access to everything. They don't need your password any longer. The only value there would be to knowing your password at that point would be if you had reused it on other sites, that they could in turn access.

Comment Re:This simply means we're succeeding. (Score 1) 235

Using wiki numbers, a loaded 787 at maximum range will do some 4.2M person-km on 101 tons of fuel. That's ~0.024kg/km of consumed fuel. A Prius with a single occupant will only do ~0.036kg/km. The aircraft is actually a third more efficient than the car. Now, you can carpool, quartering the Prius's number. Meanwhile, aircraft are not always full (increasingly rare these days), shorter flights are less efficient, regional jets are less efficient, the hub-and-spoke means you're not flying directly to your destination. On the other hand, typical car travel is single occupant, dominated by trucks, SUVs, and large cars with less than half the average rated economy of that Prius, and you're not traveling straight line in a car either.

Where did you come up with three orders of magnitude discrepancy? I could maybe see one vehicle-mile equating to 1500 in a car, which puts passenger-mile production around an order of magnitude higher.

Comment Re:Good for backhauls and maybe some DC uses (Score 2) 75

Good for backhauls

Nearly all long distance links are single-mode fiber, because multi-mode fiber results in dispersion and low signal quality at longer distances. You can't run QAM over single-mode fiber. Assuming the breakthrough here is a new modulation technique that allows for such longer distance links, you would still need to run all new fiber.

Comment Re:Perpetual motion machine of the first type (Score 1) 532

Electric motors produce motion without losing any mass

Rockets produce motion without losing mass either. The body moves in one direction, the propellant moves in the opposite direction, and the combined system encompassing both remains in place. That is exactly how an electric motor produces motion, because the system as a whole doesn't move.

so I don't really see why it's impossible for there to be some way of producing thrust in a vacuum using only energy.

It's not impossible. You're describing what's called a "photon drive". You shine light out the back, and you have an ever so slight "pressure" that drives you forward. Alternatively, someone else shines a light on your back, and that same pressure drives you forward. This is how solar sails operate. These work, we've tested them experimentally and the results match up with the theory. You just need obscene amounts of power for negligible thrust.

The problem here is now we're talking about something that is several orders of magnitude more efficient in converting energy into momentum.

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