Dill_Pickle Posted October 12, 2014 Share Posted October 12, 2014 The point of a lightning rod is to discharge the field BEFORE it is at breakdown levels...but remembering that the timing is ultimately statistical and depends on random ionization trails from cosmic rays, it's always a statistical exercise. Link to comment
Bettypooh Posted October 12, 2014 Share Posted October 12, 2014 A "Cone of protection" extends downward at a 45 degree angle from the top of a grounding point, and within that 'cone' lightning cannot make a direct strike, so a foot-long lightning rod atop a house actually only protects for 2 feet horizontally (but the grounding wire usually runs along the ridge in between them protecting it all). Now just because there can't be a 'direct strike' doesn't mean that there won't be a highly energized electrical field in the 'cone' which can still be enough to kill you but if you can get inside of such a cone and remain very un-grounded there it is safer than being out in the open. Electricity needs a path to a ground to flow so that is the most important part- provide a better path than yourself and stay ungrounded In a hardtop car (look up "faraday cage") lightning can strike inches above your head and not harm you because you are not grounded (hopefully you aren't touching any metal parts of the car!) and the car roof provides a better path so that path is the one lightning takes. To some degree it's a matter of luck. I have a church steeple across the street (hopefully grounded!) as the highest nearby object, but there are also high trees next to my house outside of the steeple's 'cone' so while my house won't take a direct hit I'm at a pretty high risk here. A strike could jump from a tree to my house when the path reaches there. I'm not worried about me, but such a strike could start a fire and would make most if not all of my electronics toast I'm playing the odds with this; then again the lightning that hits me could just as easily do so elsewhere so I don't worry about it- I just take reasonable precautions and wish for a death so quick when my time to leave the planet comes, which it someday will There's no mystic or magic or message in this, only luck, physics, and knowledge well used- or lacked as was this case Short of having a crashing airplane squashing me flat unawares I can't think of a better way to go Link to comment
widdlemikey Posted October 14, 2014 Share Posted October 14, 2014 Been on a sailboat during t-storms. Link to comment
Dill_Pickle Posted October 23, 2014 Share Posted October 23, 2014 I have certainly heard of houses burning down due to a lightning strike...someone I met once told the story of their own house meeting that fate one night when they were in bed. Link to comment
AbriForm Posted October 23, 2014 Share Posted October 23, 2014 Nothing I can really give to commiserate with this story, except to share that lightning is dangerous but avoidable. Link to comment
repetitivediaperwetter88 Posted December 6, 2014 Share Posted December 6, 2014 I was driving just the other day toward the beach like I usually do when this SUV comes flying around the corner loses control and slams into the rock wall and we come with in 1 foot of hitting eachother btw I had to swerve into the other lane to avoid collision. If I had been 1 second too early, I probably would most likely be severly injured or dead, her on the other hand is VERY Fortunate! If she had went to the right instead of the left, I would have witnessed the death of 3 people. Link to comment
Bettypooh Posted December 6, 2014 Share Posted December 6, 2014 Tain't nuthin Even though there was far less traffic and fewer idiot drivers back then, when I regularly rode a motorcycle death was one second away so many times that it hardly fazed me anymore Every time I 'kicked her over" to start riding I knew dam# well that it could be my last ride and that my riding skill and experience was only covering so much- fate had the upper hand and it always does Link to comment
repetitivediaperwetter88 Posted December 6, 2014 Share Posted December 6, 2014 Tain't nuthin Even though there was far less traffic and fewer idiot drivers back then, when I regularly rode a motorcycle death was one second away so many times that it hardly fazed me anymore Every time I 'kicked her over" to start riding I knew dam# well that it could be my last ride and that my riding skill and experience was only covering so much- fate had the upper hand and it always does Link to comment
Bettypooh Posted December 6, 2014 Share Posted December 6, 2014 SC sends driving licenses out in Cracker Jack boxes and cases of beer so that everyone can enjoy a little killing Seems that's the "normal" way it's done everywhere nowadays Link to comment
Baby Brian Posted December 7, 2014 Share Posted December 7, 2014 A "Cone of protection" extends downward at a 45 degree angle from the top of a grounding point, and within that 'cone' lightning cannot make a direct strike, so a foot-long lightning rod atop a house actually only protects for 2 feet horizontally (but the grounding wire usually runs along the ridge in between them protecting it all). Now just because there can't be a 'direct strike' doesn't mean that there won't be a highly energized electrical field in the 'cone' which can still be enough to kill you but if you can get inside of such a cone and remain very un-grounded there it is safer than being out in the open. Electricity needs a path to a ground to flow so that is the most important part- provide a better path than yourself and stay ungrounded In a hardtop car (look up "faraday cage") lightning can strike inches above your head and not harm you because you are not grounded (hopefully you aren't touching any metal parts of the car!) and the car roof provides a better path so that path is the one lightning takes. To some degree it's a matter of luck. I have a church steeple across the street (hopefully grounded!) as the highest nearby object, but there are also high trees next to my house outside of the steeple's 'cone' so while my house won't take a direct hit I'm at a pretty high risk here. A strike could jump from a tree to my house when the path reaches there. I'm not worried about me, but such a strike could start a fire and would make most if not all of my electronics toast I'm playing the odds with this; then again the lightning that hits me could just as easily do so elsewhere so I don't worry about it- I just take reasonable precautions and wish for a death so quick when my time to leave the planet comes, which it someday will There's no mystic or magic or message in this, only luck, physics, and knowledge well used- or lacked as was this case Short of having a crashing airplane squashing me flat unawares I can't think of a better way to go Link to comment
Darkfinn Posted December 8, 2014 Share Posted December 8, 2014 The knowledge part though, yeah we're still lacking on really understanding lighting for sure. Link to comment
Bettypooh Posted December 8, 2014 Share Posted December 8, 2014 Air is one of the best electrical insulators there is, so any spark which can travel through miles of air is pretty darn powerful and ain't gonna follow the instructions of mere human engineering- it's going to go pretty much where it wants to but it does follow the laws of physics in seeking the path of least resistance when grounding The bolt can be negatively or positively charged, and the ground (as well as conductors connected to it) is always close to a neutral state, about halfway between positive and negative. If there is something close to the hit whose oppositely polarized charge gives a better current path than the ground, then that becomes the path of least resistance and it will be the more likely target. Since lightning comes in both polarities you can't predict which one it will be, therefore all you can do is try to reduce the strength of any generated electrical fields where lightning might strike enough to make the 'ground' a more attractive target. This is usually accomplished by grounding, which can cause the 'protected' area to become a more attractive target- the opposite of what you're trying to accomplish And lightning can branch out even as it hits it's target, so that a nearby target receives a hit as well, just not the entire hit from the main bolt. Link to comment
Dill_Pickle Posted December 12, 2014 Share Posted December 12, 2014 The big part of the knowledge that is missing here is that when lightning strikes, the path actually follows ionization trails left in the air by cosmic rays, which are largely random. Link to comment
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