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Script notes: Electricity

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Gray
160973.  Thu Mar 29, 2007 3:17 am Reply with quote

I seem to remember we had a go at repudiating that in the meeting, as we know that charge builds up on objects (including people) just before a strike, so you really do want to be the furthest object from the charged clouds - i.e. the lowest or least 'spiky'.

 
Gray
160974.  Thu Mar 29, 2007 3:19 am Reply with quote



Simon Singh taking his trust in science to the limit, standing inside a Faraday Cage and being struck with lightning. I hope he took the change out of his pockets...

http://www.simonsingh.com/2005_Show.html

 
dr.bob
161045.  Thu Mar 29, 2007 5:29 am Reply with quote

Gray wrote:
I seem to remember we had a go at repudiating that in the meeting, as we know that charge builds up on objects (including people) just before a strike, so you really do want to be the furthest object from the charged clouds - i.e. the lowest or least 'spiky'.


I think the point is it depends where the lightning's "stepped leader" comes down. The Met Office guy refers to lightning striking the edge of a football pitch upon which a team were playing. A clear example of lightning not necessarily hitting the highest point around.

If you're the tallest thing around, you're certainly improving your chances of being hit, which is why you should crouch down if you feel yourself beginning to charge up. But the stepped leader will follow a pretty rambling path down through the atmosphere, so it's not guaranteed you'll be hit, even if you're standing in the middle of a field waving a golf club at the clouds and calling Thor's mother a whore.

Gray wrote:
I hope he took the change out of his pockets...


Of course, there being no electrical field inside a faraday cage, it wouldn't matter if he had change or not. His mobile phone wouldn't work, though.

 
Gray
161049.  Thu Mar 29, 2007 5:34 am Reply with quote

You can never fully trust these cowboy Faraday cage makers, though...

Yes, I saw the pitch strike on video once, and always thought it was strange that the lightning hit that football pitch, and not the stands. I guess it was a better conductor than them, or it was, as you suggest, just a random striking path.

 
dr.bob
161052.  Thu Mar 29, 2007 5:41 am Reply with quote

Don't forget that the stepped leader has to make its way down through an awful lot of air before it gets anywhere near any buildings or people. The relative conductivity of one bit of air compared to the bits around it will play a much greater role in deciding where lightning strikes than anything else.

 
MatC
161514.  Fri Mar 30, 2007 6:46 am Reply with quote

Link to Elephants:

British colonizers establishing plantations in Ceylon classified elephants as vermin, and paid 5 and 10 shilling bounties for killing them. Major Thomas Rogers was considered the supreme elephant pest control man; in the middle of the 19th century he killed 1,400 elephants before being killed by lightning.

S: Scigliano.

 
eggshaped
166265.  Sun Apr 15, 2007 6:19 am Reply with quote

Potato batteries

 

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