A fierce electrical storm last might made me think. If I stuck a 60 metal pole in a field filled with other 60 foot metal poles, is there some sort of thing I could do to make sure a specific pole got preferentially struck by lighting? In other words how can you make something more (electrically) attractive to lightning?
I would suspect that the better an electrical conductor it is down into the bedrock, the more likely it is to get hit. No cites for that though.
You can put an electric charge on it.
Puting a sharp point on the end in the air will help also.
Bedrock doesn’t matter. The water table is as good as it gets; once you get a conductor in there, it’s about the best possible electrical connection to Earth you can have. In most places, this is going to be a few to a dozen or so feet, give or take.
Additionally, all things being equal, a pointy pole will tend to be hit more than a non-pointy one. Experiments have shown that a slightly rounded point is somewhat better than a very sharp one, suprisingly. This is the ideal geometry for a lightning rod.
A sharp point would make it less likely to attract lightning. The point is to bleed off electrons slowly into the air to prevent a voltage difference from occurring.
NOOOOOOOOOOOOO I can’t believe an SDSAB member is repeating this myth.
The purpose and design of a lightning rod is NOT to attract lightning. It is to bleed electrons from the ground to minimize the charge difference that would cause a lightning strike.
Strap a laser to the pole.
Laser Lightning Rod
I don’t agree. The purpose of a lightning rod is to provide a safe path to ground, nothing more. “Attract” is not really a correct term; it’s more accurate to say that lighting will preferentially strike them. See here:
This is a tricky point, because the usual arguments about it are completely wrong.
There is a wonderful article in the American Journal of Physics entitled “The Lightning Rod Fallacy”, by Richard H. Price and R.J. Crowley (and based on arguments by Karel Kuchar) (Vol. 53, pp. 843+, 1985) in which they demonmstrate that the usual arguments given for “pointy tip = high field” are incorrect. They then anticipate your arguments to try and save it (probably because they mentally made the same gyrations) and demonstrate that they won’t help, either. They show you various shaped conductors and still have very low fields where the radius of curvature is the tightest. They even construct a shape that has the field the lowest where the curvature is the highest, or vice-versa. The bottom line is that the shape of the conductor is a structly local variable (I can put a point as sharp as I want over here – it doesn’t matter what it loks like elsewhere), but the electric field is a global function of that shape (the field over here depends not only upon the shape of the conductor over here, but over there as well).
Nevertheless, the sharp = high fields argument must be true at some level or under some circumstance, because that’s the experience of everyone whop works in the field. Discharges start near the sharpest points. To stop discharges, electrical workers use “corona putty” to round off sharp corners. Nobody makes insulators with sharp edges – they’re always smoothly rounded forms. And so on.
That said, the two chief factors are undoubtedly height and a good, secure, low-resistance electrical path to ground. Technically you could get better coupling with a better conductor, and empirically you’d expect that sharp point to help, too. But I’ll bet any improvement you get from either of those is negligible.
I was trying to think of a good ionizing or plasma inducing method. The laser is in use on some taser devices in place of a wire. I don’t know if they’re the civilian ones or the military though.
Somebody beat you to it. You can see those are pointy, but this is intended as a work of art, not a scientific experiment per se.
Hm, maybe you’re right.
Cecil on lighting rods: http://www.straightdope.com/columns/010824.html
Sharp edges/points on it