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Comment Re:book was boring (Score 1) 60

Reaching way, way back (with help from the Interwebs)...

Hydrazine (H2NNH2 or N2H4) has a molecular weight of 32.05 g/mol and a density of 1.02g/cm^3

1L of Hydrazine = 31.83 mol

1 mol Hydrazine => 2 mol N + 4 mol H

4 mol H + 2 mol O => 2 mol H2O

31.83 mol Hydrazine => 63.66 mol H2O

63.66 mol H2O has a mass of 1146g or 1.146L at STP

I think I got that right.

While his mental calculations weren't accurate to four decimal places, from a Fermi calculation standpoint he was close enough to the actual value to act on his estimate. He took a bunch of shortcuts but his logic "each hydrazine molecule yields two hydrogen molecules" is sound which means that two liters of liquid hydrogen combined with sufficient oxygen to make water should yield roughly two liters of water, which it actually does within about 10%.

There are certainly other examples of deviation from factual science but this one doesn't seem that bad.

Comment Re:Makes me think about North/South Korea border (Score 1) 214

The DMZ is more than 2 miles wide; a drone would be noticed long before it got to the border. I have no doubt that Great Leader 3.0 would consider that a hostile act and respond with rounds lobbed over the border. I don't think anybody in South Korea is excited about antagonizing the crackpot dictator to the north.

Comment Re:Balancing Act (Score 4, Insightful) 231

as well as whatever profits the company can get away with

Insurance companies are regulated by the states which cap their profits. It isn't about what they can get away with, they get what they are allowed. That is the devil's bargain they make for being the provider of a product required by law.

Comment Re:Electric is Evolution. Driverless is Revolution (Score 3, Insightful) 904

The problem with battery power is that as a mobile storage device it absolutely sucks compared to liquid hydrocarbons. Diesel has an energy density of 35 MJ/L. A rechargeable lithium ion battery has a density that ranges from 0.9-2.63 MJ/L. If advances in technology doubled capacity and then double it again it would still only be 1/3 as good as diesel as a storage medium. Making matters worse, the individual batteries used in a Tesla weigh 2.64 kg/L, where Diesel weighs 0.899 kg/L. Even if the battery had the same energy density it would weigh three times as much. (Yes, I know the diesel engine has mass for which I didn't account. I am only pointing out the energy sources themselves.) Musk's plant may be able to bring down the cost to make a battery but scale doesn't make the battery itself better. I can also say with a high degree of confidence that if this much money is being sunk into a lithium ion plant then no significant alternative is on the horizon, unless the whole point of the factory is home batteries, not car batteries.

Proponents keep saying that advances in battery technology will make them competitive with hydrocarbons. What they don't say is that in a world wherein a 5% improvement is a big deal the advances required exist in the realm of science fiction.

Comment Re:It's easier to ask for forgiveness than permiss (Score 1) 368

It can't be that hard if it is in range. These things move much slower than a goose or duck and one high energy lead pellet to a propeller will probably put it out of service. These things are an awfully big target compared to the dove and quail people hunt.

Comment Re:The Keystone Pipeline already exists (Score 1) 437

In addition to the $5B GS got from Buffet, GS also got $10B from the US Treasury. For the use of the Treasury's money GS paid about 23%. For the use of Buffet's money the cost was around 100%. I don't know what Buffet did, but GS would not have paid four times as much to use Buffet's money unless it truly was a deal they could not refuse.

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