# Search results

1. ### Electric Trains and The Third Rail

So we're always told not to touch the third rail, as it's at a very high potential. Makes sense. But how does return current work in such a system? Let's say there is some load (the motor - we'll simplify and assume DC). One terminal of the motor is connected to the third rail, what's the...
2. ### Struggles in school(EE) and some advice needed.

First of all, you need to sleep more. I know you're probably exaggerating when you say 3 hours, but 8 is really what you should be aiming for. I think I'm a pretty bright guy in some areas, but I'm a wreck without sleep. This isn't folksy listen-to-your-mother advice, there is plenty of hard...
3. ### Giant VU Meter Project

Ah, this is the insight I was hoping for! Where can I find such triacs/opto-couplers?
4. ### Giant VU Meter Project

The idea is to put our own lamps in the windows, and only light up one column of windows. The relays need to switch less than an amp (we're talking one or two 100 watt bulbs).
5. ### Giant VU Meter Project

Hello all, I'm a freshman electrical engineering student at the University of Kentucky. I'm also a DJ at http://wrfl881.org" [Broken]. I was browsing around the awe-inspiring http://www.blinkenlights.de/" at MIT. Now on our campus we have a convienently tall building atop which sits our...
6. ### Draw mohr circle using C programming

You need a graphics library. Your instructor almost certainly had one in mind, but if not try http://www.libsdl.org/index.php" [Broken].
7. ### Can heat exit the atmosphere?

Think of visible light. Visible light obviously reaches us from the sun. For a long time scientists assumed light must propagate like sound, through a medium. They (usually) called this medium "aether". Relativity was kind of the final blow for aether-theory. Turns out light (a type of...
8. ### Universal laptop power supply?

I am certain there is no switch. I can move this back and forth between two different laptops, requiring different input voltages, without issue. This is in line with the advertising. The mystery remains... :confused:
9. ### Origin of PF

How and when did these forums come into being? Are they run by a company, or individuals? Is it a hobby or business?
10. ### Universal laptop power supply?

"Universal" laptop power supply? My father had an extra laptop lying around that despite being old and having had it's monitor seperate from it's chassis was in perfect working order. Or such was the case several months ago - I dusted it off today and it refused to start. I got out my...
11. ### Acoustic Modem

Does this need to be acoustic? Why not use radio?
12. ### Schools Graduate School in German-speaking Country

I am interested in doing exactly the same, though I am just entering college. My school has a German Engineering program whereby students can work for a German engineering company (here or, preferably, in Germany). I highly reccomend, if at all possible, going to Germany before committing to...