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Comment Re:That... (Score 2) 242

The 9V battery probably saw precisely none of that voltage. Chances are, the way it was set up is to put 75kV on one post and -75kV on the other, giving a potential difference between the posts of 150kV. The electricity then arced from one post, through the metal in the CD, to the other post because the metal provided a path of less resistance than the air over the CD. Once the metal was gone from the CD, it arced though the chassis of the motor mostly (from what I could see). There was no reason for the arc to pass through the battery terminals since the chassis provided a much shorter path.

Now, had they placed the battery in line with the arc, that probably would not have ended quite so well...

Comment Re:If you ain't moving.... (Score 1) 741

While some knowledge is made obsolete by the advancement of technology, it does not mean that we cannot also become as competent with such knowledge as our forefathers were. We have the distinct advantage in the ability to research and rapidly absorb volumes of data on a particular subject (something that would not have been possible 100 years ago - we have instant access to just about any piece of knowledge we need, something that has never before been available) means that we can become adept at a particular task much faster than our forebars could.
Note: I'm saying much faster, not instantly. Learning to become a 'period' blacksmith will still take months, if not a year or two. However, a smith in those times would take a lifetime learning their craft, it is handed down through the generations etc. But learning how to make a spear? Let me look up a couple articles on paleolithic spear design and I bet you within a day or two I can knock out some pretty effective spear tips.

Comment Re:FAIL (Score 2) 300

A resonant antenna can be found in PCB traces that are the right length, yes. These traces are usually shielded to the nines, so that stray signal does not get in. Transmission cable is also shielded to prevent extra noise coming in (there's enough of it at the antenna already). Non-shielded cabling (i.e. power) is usually protected from the sensitive stuff by means of an inductor (often called an RF choke) to block off as much of that extra noise as possible. On top of that, Antennas can be designed with a small narrow bandwidth amplifier to give the signal a boost as it enters the system, and also reduces the incoming signal bandwidth to that of the preamp, cutting out more noise. The way I see it, if they're getting enough interference from a standard strength wi-fi signal to bork the system, they have some major design flaws to work out.

Comment Re:Stupid humans, why do we still need this crap? (Score 1) 198

It's the combination of environmental, social and internal logic. It's the same reason people get motion sickness, vertigo, and a host of other problems caused by conflicting signals. Going back to my initial analogy, you're used to getting up at 2am, when it's light outside, eating lunch at 7pm, when the sun is at it's peak and going to bed at 6pm when the sun has long since set. You are used to this; you've done it for (presumably) a few decades. Now, you travel somewhere (alone). You are informed that you have to wake up at 7am (lunchtime) when the sun is just coming up (you're used to 7am being peak sun time), eating at noon (which your brain thinks is sunset) and sleeping at midnight (holy shit! I need to wake up soon!).
Now, not only do you have jet lag to worry about, you also have to remember inane shit like what time lunch is in a foreign country, when do stores open and close, when should I wake up to be in sync with the rest of the population etc. instead of just setting your clock to the correct standard time for the particular locale and calling it a day.
Yes, it's possible to just deal with it, but when there is a decent system in place to alleviate the issue to the point where it's actually pretty easy to pick up and go when you land in a foreign country, I'd have to say that I would prefer it this way.

Comment Re:Stupid humans, why do we still need this crap? (Score 5, Insightful) 198

Let's say you live your life in New York, where the sun is at it's peak at 7am (UTC -5 hours, 12:00pm-5 = 7:00am). You are used to waking up at 2am, having lunch at 7am and going to bed at 6pm. You then travel overseas, where the sun peaks at 1:00pm (UTC +1 hour). Now, instead of setting your watch and waiting for jet lag to run it's course, you now have to re-wire your brain to continuously remember to eat lunch at 1pm, not supper and that bedtime is somewhere around midnight.

At least with time zones (as fucked up as the current system is), you can travel anywhere, set your clock to the local time and have a general estimation of the day. Wake up at 6-7am, eat lunch at noon, supper at 5 or 6, go to bed around 11. Makes things much easier on our dumb little brains.

Comment Re:Temperatures plummet in Hades (Score 1) 176

uhm, well, let's see here... geo-tagging is being used by both Google and MSFT in various applications (WP7, Bing maps, Andriod, Google Maps etc). Therefore, having this patent floating around saying that they can't use it is equally bad for both companies.
Being competing companies does not mean that it may not be in their best interests to team up every so often to take on a threat to both.

And for all those who comment about Google 'doing no evil' and partnering up with Microsoft, keep in mind that they're also protecting the other 395 companies being sued and encouraging competition in this particular marketplace.

Comment Re:before you do it (Score 1) 312

How many movies have been made about computers going apeshit and killing/enslaving everyone? has that stopped our research in computer technology?
What about alien invasion movies? According to those, the signals we send off into space are luring aliens to come here and destroy us!
If it weren't for people doing stuff "just cuz we can lulz", we'd still be back in the stone ages. Discoveries and progress are made by people trying stuff simply to see if they can do it.

Comment Distracting? (Score 1) 804

I think having laptops in class should be assumed these days. I bring mine with me every day; I use it to do assignments, take lecture notes, look up stuff the teacher is talking about for more details and so on. Yes, I do occasionally peruse Facebook and /., however, I don't allow it to distract me. The OP saying that someone's screensaver is enough of a distraction should probably get some ritalin or find a more interesting subject to study. People who want to be distracted, will be. whether it's a laptop or just doodling shit in their books, it's gonna happen.

Comment Re:What we do/don't need in Calculus. (Score 1) 1153

I'm currently a second year engineering student. In first year, we had several mature students (aged late 20's to late 60's) myself included. The people that survived were the ones who took advanced math courses in high school, or retained their prior knowledge of math. Those who did not have a strong math background dropped out fairly quickly, even though the first term math was considered a 'remedial' math course (covering basic algebra and trig, stuff I did in grade 10). Those with poor math backgrounds quickly floundered and failed out (a couple of the more tenacious types stuck on, but they had to re-take the course and are now severely behind).

But really, if we're only going to teach the basics to everyone and leave specialty courses to when you've chosen your field, then why not eliminate the need for English after grade 10 for those not pursuing a degree in it? get rid of all science classes for MBA and Economics students too; no more history classes unless you plan on being a history major or social science classes unless you're gonna be a sociologist.

The point of high school is to provide a well-rounded, general education is just about every academic discipline. To do this, a certain level of math proficiency is required. While I agree that calculus isn't necessary for most students, normal math classes all through will be. Even if you will never again have to sketch a parabola, or solve two unknowns in two equations, having a knowledge of math that is significantly higher than required will not only make the maths that you need to know for life much easier, it will also enable you to expand your horizons later in life if you choose to.

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