4 ms·
It's a law of nature that you can build up a lot of energy in something by adding just a tiny bit of energy each pass. This was a bitter team that was beaten an
by sudont 15y ago
It's a law of nature that you can build up a lot of energy in something by adding just a tiny bit of energy each pass. This was a bitter team that was beaten and decided to use physics to add this tiny bit of energy each time the tape rewound--mind you, at a steady rate chosen to add in the energy perfectly-- to embarrass somebody who had beaten them.
Or is my understanding of a tape drive incorrect, and they would wind and unwind at a set rate? Because the original article said that it would often stop, rewind, move forward to retrieve data.
- sp332 15y agoI don't think it really wound all the way to the ends of the tape, like my link said. I think it just wound forward for a set amount of time, and then back, to match the resonant frequency of the device. Also, I think the point is that it's the Black Team's job to minimize bugs shipped, and they were really impossibly good at it. It was the programmers' job to write bug-free code, and this guy was inspired by the Black Team to write perfect code. It seems like both sides were doing exactly what they were supposed to do.
- Symmetry 15y agoOn the other hand any physical system in motion is also loosing energy constantly to friction, air resistance, and other factors. Because of that and because the winding/unwinding description seemed implausible I strongly suspect the story is apocryphal.
- benpbenp 15y agoSorry to nitpick, but I think this is a good thing to know. Apocryphal means "of doubtful authenticity", not mythical or false, which is the how you seem to be using it. The story is clearly apocryphal.
- Symmetry 15y agoNo need to be sorry, I'll know to use it correctly in the future. :)
- jcr 15y agoI think you're underestimating how mechanical old hardware really was. There's the classic story of "Walking Drives" from esr/jargonfile: http://dictionary.die.net/walking%20drives http://dictionary.die.net/walking%20drives Or search for "washing" here for the story about huge DEC drives being ripped apart: http://www.rinkworks.com/stupid/cs_drives.shtml http://www.rinkworks.com/stupid/cs_drives.shtml Old hardware employed a lot of force, so "bad things" (TM) really could happen.
- kragen 15y agoNormally you'd expect the Q factor of a standing tape drive to be small enough that you'd be unable to come anywhere close to knocking it over with the tiny kicks from the reels.
- redthrowaway 15y agoWouldn't you have said the same thing of the Tacoma Narrows Bridge?
- kragen 15y agoI probably would, yeah, unless I actually took the time to examine the design and calculate Q. I'd've been wrong in that case. Actually, I probably wouldn't, because if it had occurred to anyone that they ought to ensure that the bridge design had no high-Q vibrational modes, the problem would have been found and averted before the first caisson was sunk.
- redthrowaway 15y agoI have the sudden urge to build a weighted cabinet and see if I can knock it over with fast-forwards/rewinds. I've got a couple engineer friends who could run the numbers, but nothing would quite compare to the satisfaction I would feel if I could actually do it.
- atamyrat 15y agoCan't we get Mythbusters to do it?
- redthrowaway 15y agoI think that's actually a great idea. Anyone know how to throw suggestions their way?
- sp332 15y ago
- gaius 15y agoExactly. How much of IBM's money had gone into developing the new product? How many sales did they lose as a result of this public humiliation? That's the problem with "elite" teams in organizations. You don't get the actual elite. You just get the best connected, and they think they're untouchable.