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Comment Re:Trickery. (Score 1) 324

Yes, it's possible to find MicroSDs -- if you do a full-up fine-tooth-comb search. Which takes hours and pretty much destroys everything in its path. If you've really pissed off the Powers That Be, they might. Then again, they've probably done the same thing to your office, home, car, and anything else you've been near recently anyway so why start worrying at the airport?

Otherwise, the major danger is that your brand-new Alienware machine looks like it would be better off in someone else's collection and the "confiscation for the sake of search" is just an excuse. Which is why you're better off without it (get another on arrival) or at least leaving the hard drive at home. The MicroSD chips aren't what they're after and finding the one in the heel of your shoe is more trouble than it's worth.

Comment Short answer (Score 1) 324

Don't have a drive in it. Don't have bits that they can claim to find suspicious. No excuses, because even (or perhaps especially) if they don't find anything on your laptop they'll confiscate it anyway to have the boys back at the shop take it apart ten ways from Sunday.

When you arrive, buy a new drive and load it up. How? Well, if you're visiting a field (or home) office, they'll have a disk image handy for you to use. If there are private bits that you haven't shipped over yet (SRSLY? They travel faster than you do, after all) then you can take them along. The border peeps aren't interested in doing cavity searches on everyone, after all, and short of shredding all of your clothing as well as the rubber-glove treatment they're not likely to find a micro-SD.

Comment Re:Higher voltages (Score 2) 147

Really??? So if I connect two (super)capacitors in series, thereby doubling the voltage limit, I have somehow squared the energy storage!

You've also halved the capacitance and doubled the volume. So: twice the voltage (4x), half the capacitance, (0.5x), and twice the volume (0.5x). Looks like your energy density didn't materially change.

Comment Higher voltages (Score 4, Informative) 147

Well, yes, the amount of energy stored goes up as the square of voltage for a given capacitance. However, for a given dielectric getting twice the voltage requires twice the thickness and cuts the charge in half -- so the energy per unit volume is unchanged.

Which shouldn't be surprising since the energy is stored in the dielectric by (e.g.) straining the molecular structure of the material.

The biggest reason for going to higher voltages is to reduce the interconnects, which get enormous at low voltages and high currents. (Cross-sectional area goes up inversely with the square of voltage for any acceptable IR loss, which is why long-distance power lines run at scary voltages.)

I have a theory that it's impossible to prove anything, but I can't prove it.