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I was reading "The Physics of Superheroes" by James Kakalios and I came across the following paragraph:

In one scene during their climatic battle, Spider-Man manages to deflect an electrical bolt that Electro has hurled at him by tossing a metal chair over Electro’s head. “Anyone with any knowledge of science knows that anything metal can act like a lightning rod,” Spider-Man says, lecturing Electro, “as this steel chair is doing!” Actually, Spider-Man’s mistaken understanding of how lightning rods function suggests that his allegedly advanced knowledge of science isn’t all it’s cracked up to be. The electrical bolt is shown arcing away from Spider-Man and chasing after the soaring chair—even though the chair is not electrically connected to anything! Why would Electro’s lightning bolt be pulled toward the chair, metal or not, if once it reaches the chair there is nowhere for the electrical current to go?

I'm not sure about this. The chair doesn't need to be at Earth's potential to be hit by Electro's bolt. It only has to be at a lower potential than Electro. It doesn't matter that the current cannot exit the chair: some charge will flow from Electro to the chair, enough to bring the chair and Electro at the same potential, after which (I guess a microsecond or so) the current will stop. After all, airplanes are big flying metal objects,but they can be struck by lightning. So why shouldn't it be the same for the chair?

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  • $\begingroup$ -1 Not clear. What are the physical properties of this fictional "electrical bolt"? Without identified realistic properties I think any answer can only be a matter of speculation. $\endgroup$ – sammy gerbil Dec 31 '17 at 16:28
  • $\begingroup$ @sammygerbil I cited the piece from Kakalios as accurately as possible. Do you want me to cite the full chapter, with his description of Electro's powers? Would that help? The question will become very long though. Otherwise, can't we just consider that the "electric bolt" is a lightning which goes from Electro to the metal chair? Would that make sense? We could hypothesize that Electro is at an extremely high potential with respect to the ground, and isolated from it by his "magic shoes". What do you think? Does this make the question better defined? $\endgroup$ – DeltaIV Dec 31 '17 at 18:02
  • $\begingroup$ No I don't think it is necessary to post the whole chapter. But I do think it is necessary to make clear what is the real-world scenario which you are asking about. (Speculations about superpowers are off topic here.) So the "electric bolt" is just the discharge of electricity from Electro, as from a Van de Graaf generator or a cloud? $\endgroup$ – sammy gerbil Dec 31 '17 at 18:21
  • $\begingroup$ You seem to be agreeing with Kakalios that after the discharge has reached the chair, the flow of current will stop, and the "bolt" will not continue chasing the soaring chair. If you agree about this, what is it that you disagree about? There is no point asking about something which you agree with. $\endgroup$ – sammy gerbil Dec 31 '17 at 18:25
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    $\begingroup$ A few instants before a lightning bolt actually penetrates the air, the air itself will become highly charged, with lots of ions flitting about. A metallic object such as a metal chair, with lots of points and angles on it, will tend to "align" the ions in the air in a way that will "attract" the lightning. Whether this effect is sufficient to actually divert a lightning bolt, of course, is largely speculation. $\endgroup$ – Hot Licks Jan 1 '18 at 0:33
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On the one hand, the capacitance of the chair is very low, so, if it is not "grounded" in some way ("nowhere for the electrical current to go"), its potential will quickly become the same as that of the source of the lightning. On the other hand, a lightning follows the path of the least resistance, so the chair can indeed "deflect" a lightning: after the lightning hits the chair, it can move in a different direction, say, towards the ground, rather than towards Spider-Man. So, while Kakalios makes a good point, Spider-Man's ignorance of science is not obvious in this episode.

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  • $\begingroup$ If I understand you correctly, you are saying that even if the chair has been low capacity, it can still deflect the lightning away from Spider-man and towards the ground. Right? Can you just explain this point more in detail? Is this related to the fact that the chair is a conductor? $\endgroup$ – DeltaIV Dec 31 '17 at 23:28
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    $\begingroup$ @DeltaIV : yes, and yes. As the chair is a conductor, there is a better chance that the path of the least resistance will go through the chair. Thus, the chair can deflect the lightning and thus increase the chance of the lightning hitting ground or some other object, rather than Spider-Man. And I should have used the word "capacitance" (edited). $\endgroup$ – akhmeteli Jan 1 '18 at 0:11

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