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Imagine an individual touched a high voltage line (like a bird) without touching any ground. For sake of illustration, imagine that this high voltage line was at a 100 Exavolt potential.

Would the bird or person notice anything when they touched the line, since they were not also touching ground?

Now, imagine that the bird flies away from the line and lands on a ground line, after having touched the hot line (i.e. the bird is no longer touching the hot line and is far from it). Would the bird notice anything in this case?

Obviously, if the bird touched both at the same time it would be electrocuted.

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  • \$\begingroup\$ Is the high voltage line carrying AC or DC? Remember that a bird or person will have some capacitance. \$\endgroup\$
    – tangrs
    Commented Jun 14, 2015 at 1:12
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    \$\begingroup\$ @Gregd'Eon - Similar - but Joe asked about a "stupidly high" voltage of E18 volts compared to the "mere" Giga volts discussed in the other question - allowing a much different and simpler approach to produce an astounding and different result. It's not often that you get to store the energy of a million Tzar Bomba 25 megaton bombs in a 1 picoFarad capacitor. \$\endgroup\$
    – Russell McMahon ♦
    Commented Jun 14, 2015 at 7:35
  • \$\begingroup\$ @Russell Right - I only noticed the difference when you posted your (top-notch) answer \$\endgroup\$
    – Greg d'Eon
    Commented Jun 14, 2015 at 12:31
  • \$\begingroup\$ 50 megaton actually - brain said Tsar Bomba was 50Mt design but 25Mt with lead tamper, but it was actually 100 Mt design reduced to 50 Mt actual by using a lead outer shell rather than Uranium. The "test" was well known of in advance. The US sent monitoring aircraft, as one does. One probably untrue but good story says that the US sampling 'plane was closer to the bomb than the release aircraft at the moment of detonation and came back with charred paint. Maybe not - but if it has been a 1 Exavolt sparrow they would have not been so lucky. And for a 100 Exavolt sparrow ... \$\endgroup\$
    – Russell McMahon ♦
    Commented Jun 14, 2015 at 19:44

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Imagine a bird touched a 100 Exavolt potential line without touching any ground.
Would the bird ... notice anything when they touched the line ...

Lets make it a sparrow.

No, the sparrow would not notice a thing.
Nor would any observer within a radius of about 10, or 20 or maybe 40 or 50 km.
Outside that radius degree of noticing would be variable and duration of noticing would be varied and the lucky ones may not notice.
Somewhere from around a few 10's of km out an observer would notice, briefly.
Somewhere, beyond many tens of km the observer may live.
(The 1 microsparrow Tsar-Bomba had a total destruction radius of 15 miles.)

Because:

See references at end for formulae et al

An Exavolt = 10^18 volt or a billion billion volts (US billions).

Preventing the line arcing to ground will be "an issue" - lets just assume it's high enough. Hanging from balloons maybe.

Self capacitance of an isolated sphere is 4.Pi E0.R
Assume a sparrow approximates to a 1cm radius sphere. This assumption will be found to be non critical. Capacitance is about 1 pF (1E-12F).
This is an indicator of how much charge a given object can hold.

Let's be conservative and work at 1 Exavolt rather than the 100 suggested.
It will suffice.

Energy transferred to 1 capacitor by a potential change = 0.5 x C x V^2
Here C= 1E-12, V = 1E18
Energy = 0.5 x E-12 x (E18)^2 = 5E23 Joule
1 Terrajoule = E12 joule.
1 Petjoule = E15 joule
1 Megaton =~~ 4 Petajoules.
So sparrow energy = 5E23 / 4E15 ~~= E8 megaton Largest H bomb ever = Tsar Bomba at 50 MT.
So sparrow has more energy than 2 million or so of largest H bomb ever detonated.

After making allowance for bad assumptions, vague generalisations, specious thinking, general woolliness and lack of coffee, and adjusting everything down generously at all stages, it seems safe to say that your sparrow is toast (and very very very well vaporised toast to boot) AND that living anywhere within about say 100 km of said power line or of said sparrow is liable to be hazardous to your health.

Tsar Bomba = 50 megaton ~= 1 micro-sparrow at 1 Exavolt.

enter image description here

Related (maybe :-) ):

Capacitance - see self capacitance

Isolated spherical capacitor

Nuclear weapon yield

TNT equivalent

TEV and mosquitoes

LHC & TEV ...

Electrostatics

Mega Giga Tera Peta Exa Zetta Yotta Joule

A bomb energy

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    \$\begingroup\$ I see the charming phantom downvoter has been here again. I wonder if they're the phantom close-voter as well? I do (super briefly) ponder the mindset and intellect of the phantom. Not useful? The question was always flippant and never super serious. But it highlights, if ever so roughly, the energy levels present when "normal" things are taken to extremes. 1 million biggest-ever H bomb energies in a 1 pF capacitor. Wow. What does that tell us? Not much maybe. But it seems to set an upper (half sensible) level to this class of question. I wonder what it takes for an answer to be deemed useful? \$\endgroup\$
    – Russell McMahon ♦
    Commented Jun 14, 2015 at 19:50
  • \$\begingroup\$ The downvote was mine, and I wrote but then decided not to leave a comment because I thought it was better to cast an honest vote while trying to avoid unnecessary conflict. I awarded it because I felt the answer did not accomplish anything apart from mocking the asker for their "stupid" choice of potential difference. This much energy could also be imparted to a sparrow by accelerating it close to the speed of light. Such an example helps to show that merely to impart a gigantic potential energy of course does not cause it to explode. \$\endgroup\$
    – Oleksandr R.
    Commented Jun 14, 2015 at 22:37
  • \$\begingroup\$ Your having mentioned self-capacitance could arguably be considered useful, except that the answer of Victor Popescu in the duplicate thread has already dealt with this, while that of Roger C. addresses the phenomenon that the OP was probably really asking about. Thus I absolutely stand by my assessment that your answer was not useful. And no, I have never downvoted you before. \$\endgroup\$
    – Oleksandr R.
    Commented Jun 14, 2015 at 22:47
  • \$\begingroup\$ @OleksandrR. Most important point arising: I was not intending to mock the asker and I'm sorry if it came across in that manner. It was aimed to be a somewhat fun response to a somewhat [tm] unlikely question. I said "stupidly" high (with the quote marks) in a comment response with the intention of showing that the answers were so different due to the immense potential in this case. || Other: It's always nice t know what a downvoter is thinking - even if one does not agree :-). Victor's self capacitance idea wqs only partially developed but was Ok, but the he and others tended to deal .... \$\endgroup\$
    – Russell McMahon ♦
    Commented Jun 14, 2015 at 23:04
  • \$\begingroup\$ ... in "safe" currents whereas this question had absolute energy as its dominant aspect. | Yes your near light speed sparrow and my Exavolt sparrow are both 'potentially OK" if the potential remains unrealised. | Which phenomenon he was thinking of would be irrelevant to the sparrow - or to him if he was the observer :-). \$\endgroup\$
    – Russell McMahon ♦
    Commented Jun 14, 2015 at 23:08

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