The concept of electricity as a fluid which flows through conductors is what we call an analogy. You think of electricity as a flow of stuff from an area of high electric potential to an area of lower electric potential, and resistance as a sort of constriction or blockage of the path the stuff is taking, but the actual stuff doing the moving isn’t really moving that much. There’s no “flow” of electrons moving from one end of the circuit to the other, there’s simply a propagation of waves. And this has pretty much nothing to do with the discussion at hand, the gist of which is that the tires could provide ten million times the electrical resistance that the atmosphere does, and the bulk of the current would simply take the less resistant path. In other words, any insulating property the tires may have is pretty much completely irrelevant.
BTW, I think I heard someone say “centrifugal force” in another thread. We’ll hold the fort here while you take care of that.
A couple of years ago a coworker’s car was almost struck while driving. It was a mid 90’s Toyota Landcruiser. He saw the bolt impact a couple lanes away & a hundred-ish feet ahead.
The engine died immediately. Aftter he coasted to a stop the engine restarted, but ran like crap. The auto transmission would operate in 1st & 2nd but wouldn’t go into 3rd or higher.
He limped into a nearby Toyota dealer. Later they told him the main computer was fried, but the vehicle was equipped with a non-computerized “limp home” mode that worked well enough to get him into the dealer. $1500 later he was back in business.
We both doubted the EMP from the bolt would be enough to do the damage, so we suspected there was a side strike that actually hit his vehicle. Never found any other damage.
Lighting - random, extremely powerful, and all-but-instant. You can see why the Ancients equated it with their god(s).
We did this once before, but it appears to be too old to search. in that thread, I mentioned of a case where a car was struck by lightning, and it destroyed every electronic control unit on board. Several small salvage rebuilders lost their ass trying to restore it to running condition.
Someone else posted a link to some pictures of a van that got hit while parked a fire resulted inside the van, or at least it looked that way.
So I feel safe is saying, your damage may vary.
Centrifugal force is a completely real force inside a rotating frame of reference. It’s only a fictitious force when examined from an inertial frame from reference. Ask any physicist.
BTW: Look up “flow” some time. At least one of its many definitions involves the flow of “stuff.” Like photons.
I’ll agree the concept of electricity flowing like water is flawed, but the term “flow” itself is not inherently incorrect. Electrical engineers use it, and not just in everyday speech, but also in professional papers. That’s good enough for me.
A lot of EEs like to say “current flow” or “flow of current.” :dubious: I’m also guilty of it. It’s a sloppy usage of terms for a couple of reasons. For one thing, current doesn’t flow - ***charge ** * flows. Secondly, we often use the “conventional direction” for the flow of charge, which is ass-backwards to what’s really going on.
I disagree. Not that charge flows–surely it does–but that current doesn’t. But, I think in order for any of this to make sense, we have to understand what our definitions of “flow” are. There are a number of definitions of the word here. I see a number of them which apply very well to current, don’t you?
Bottom line is: current flows because we have defined it to be so.
I saw a video of a couple of kids walking in a rainstorm when apparently lightning struck just a few feet from them. The weatherperson corrected this and said that what had actually struck was one of those streamers that go up from the ground to meet the step leader, but this one didn’t actually meet the step leader so it wasn’t a full on lightning strike. I wonder if a lot of people that think they get struck by lightning are actually hit by things like this, which in my mind explains why they survive. I find it very difficult to beleive that someone can get hit by a full on bolt of lighning and survive.
(Feel free to correct my vague understanding of the process.)
I can’t seem to find many picture of lightning damage to cars, but googling “aircraft lightning damage” yields several good pictures. There seems to commonly be round “bullet-hole” looking entry marks, and I assume either similar exit marks, or burn marks of some sort. I’d expect that a car getting hit directly by lightning would have similar damage.
Lightning strikes have caused accidents, though I haven’t read all the reports to see what kind of instruments/controls were affected and whether they correlate to cars at all. I do notice that on an NTSB search using only “lightning” as a keyword, the fatalities are all Part 91 (general aviation) and not Part 121 (Commercial transportation). Would a car resemble a Boeing 737 or Airbus 319, or would it be more equivalent to a Cessna 495, a Beech 495? I also haven’t read the reports to see if the lightning caused the fatality/injury, or if the ground did
So what was that little “this ought to be good” throwdown about? Did you disagree then, but I convinced you, or do you just enjoy making people go on the defensive when it’s not really called for? (rhetorical question; the answer is obvious)
I’ll ignore your claim that the answer is obvious, because apparently it isn’t. You objected to the term “flowing,” full stop. You never said anything about water. And neither did I until CM brought it up. If you don’t see a difference between “flowing” and “flowing like water,” well, that’s your problem.
Actually, I didn’t, full stop. You and I both know (especially now that I have humored you and elaborated) that I wasn’t referring to the term “flowing” by itself, but the commonly-understood-to-be-an-analogy-which-you-yourself-acknowledge-is-flawed concept of “electricity flow.”
And the entire point is that I don’t object to this. Mental models are useful, even when they’re not 100% correct. It’s going around picking pedantic fights that’s not useful.
Actually what started this was my objection your claim that lightning follows “the path of least resistance.” This is neither a useful nor correct model.
For purposes of deciding whether tires acting as insulators is going to make any difference, sure it’s useful. I already explained this: the tires could be magical perfect insulators and it will basically make no difference, because the bulk of the current will just follow less resistant paths.
