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Comment: Re:For all of you USA haters out there: (Score 5, Interesting) 298

by quenda (#48931279) Attached to: Why ATM Bombs May Be Coming Soon To the United States

Never mind the antiquated banking system, lack of metric or the crippling health-care system - explain why pennies are still in circulation in the US!
There is a fundamental conservatism in the US that makes it exceptionally difficult to change anything at the national level.
It is something of a paradox, since at the local level, Americans are so adaptable and innovative.

Comment: Re:The Great Filter (Score 1) 191

by quenda (#48930099) Attached to: The discovery of intelligent alien life would be met predominantly with...

Of course, humanity has grown up with a culture where 99% of fictional alien encounters end incredibly badly...

This is based on solid experience. Name one single example of a primitive race benefiting from contacting a more advanced race.

If we discover evidence of a remote civilisation (e.g. SETI), I will be happy as you say. But in the far more unlikely event of meeting aliens here, I will be extremely fearful.

Comment: Re:^^Winner (Score 1) 216

by quenda (#48910277) Attached to: Doomsday Clock Moved Two Minutes Forward, To 23:57

I don't know a lot about the US. But of course it has always been ruled by the elite - the founding fathers were from the 1%, and the "revolution" was just a change of management that did nothing to benefit the common man. But while fearful of mob rule, they felt a greater duty to the commoners than today's politicians seem to. (or at least the white commoners)

  The recent development I think is the power of the corporations, rather than just wealthy individuals. The corporations seem to have less collective conscience.

Comment: Re:^^Winner (Score 1) 216

by quenda (#48901437) Attached to: Doomsday Clock Moved Two Minutes Forward, To 23:57

They might even get away with a C-

For what? Voting in a dictator counts as a democracy, does it? The Russians dabbled in democracy, and then rejected it.
In the context of an English-language forum, modern democracy means a multi-party parliamentary system with rule of law, as invented by the British. Without an effective opposition, the parliament becomes a rubber stamp for the executive, and politicians stop caring about votes. In some countries this can work better than a multi-party system, but it functions very differently from a democracy in the Western sense.

Comment: Re:There Is A Better Solution (Score 1) 83

by quenda (#48901333) Attached to: NASA Considers Autonomous Martian Helicopter To Augment Future Rovers

Nature evolved legs for dealing with rough terrain. NASA needs to start using walking rovers, not rolling rovers.

Ah, but when man first invented the wheel (long after metallurgy and shipping) there was a great thunderclap from the heavens as God slapped his forehead and said "Why didn't I think of that?".

We can look to nature for inspiration, but have you ever seen the old film of the early plane with flapping wings?

Comment: Re: Lift? (Score 1) 83

by quenda (#48901257) Attached to: NASA Considers Autonomous Martian Helicopter To Augment Future Rovers

No, a balloon is not so easy. With 1% the atmosphere, you need a 100X bigger balloon than on earth. And mind those winds.

But an aerofoil / rotor has advantages - first it only needs 40% of the lift (lower gravity) .
More significantly, while lift is linear to air density, lower pressure also means reduced drag on the rotor, allowing faster rotation and/or bigger rotors (lift proportional to area).

Drag formula is similar to lift, so with the same power, you can spin the rotor 10x faster to get the same drag and lift as on earth. (force = density x velocity squared ... )
In practice, you make the rotors bigger and slower, but you get the idea . Aerofoils work better than balloons in low pressure.


Comment: Re:Other than the obligatory security theatre... (Score 1) 110

by quenda (#48897389) Attached to: Bomb Threats Via Twitter Partly Shut Down Atlanta's Hartsfield Airport

Remember 9/11? You damn well better believe the fighters would shoot the plane down if it strayed.

Are you subscribing to the conspiracy theory that the 4th plane was shot down?
And the authorities cannot distinguish between a bomb-threat and a hijacking?

Comment: Re:Hold your horses (Score 4, Informative) 211

by quenda (#48891283) Attached to: At Oxford, a Battery That's Lasted 175 Years -- So Far

FTA, it takes around 1 nanoampere to ring the bell once. It rings around around 2 Hz. Thus it takes 2 nanoampere a second, which works out to 7200 nanoampere-hours.

Ouch! Your bad maths is making my head hurt. Amp is a measure of current, not energy or charge.
  A nA is one nano-couloumb per second. WTF does "nanoampere a second" even mean? Current acceleration?
  One nano-Amp for an hour is precisely one nano-Amp hour, duh!
Better known as 3.6 microcoulombs. At 2kV, it is 7.2 milli-joules of energy.
For that idiocy you get a +5? Mods need to stay in school.

The better AAs produce 3 amp-hour of power. That is 3000000000 nanoamperes.

FFS! First you equate amp-hours with power, and then you equate it with amps. Where did the time unit go?
Your 3AHr battery at one nano-Amp will last 3 x 10 to the 9 hours, or 342,000 years. (neglecting internal leakage :-)
Of course you will need a few of them in series to equal the 2kV of the Oxford Bell.
What has happened to /.?

(disclaimer: After that rant, I'm almost certain to have made an error myself.)

Comment: Re:Again, why? (Score 4, Informative) 169

by quenda (#48890685) Attached to: Google Just Made It Easier To Run Linux On Your Chromebook

If you have a Chromebook, Google has already made ChromeOS support anything that the Chromebook will have to do.

Oh, no they have not.

A macbook can install 3rd party apps out of the box. It is not locked down.
But if you want Skype, Minecraft, or Steam for example, on a Chromebook, you need to unlock it (developer mode, unsupported) and install a full Linux environment first.

But yes, no need to replace ChromeOS, just supplement it.

"Free markets select for winning solutions." -- Eric S. Raymond