What happens to the current when lightning strikes a swimming pool?

AI Thread Summary
When lightning strikes a swimming pool, the electrical current primarily dissipates along the water's surface rather than penetrating deeply. This phenomenon is attributed to the "Skin Effect," where high-frequency alternating currents travel predominantly on the surface. The current can spread out significantly across the water surface, potentially allowing individuals underwater to survive a strike. The discussion references external resources for further technical explanations on this topic. Overall, understanding the behavior of lightning in water is crucial for safety considerations.
klng
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Hi all,

In response to the above question, i read somewhere before that when lightning strikes a pool, or the sea, the current will dissipate along the water surface. The current will penetrate only to a small depth into the water.

A simple search on Google throws up the simple explanation "The Skin Effect". Lightning is described as a high frequency Alternating current.

Can i have some help to explain - in simple terms - this spreading of current over water surface?In addition, how far on the water surface does the current actually spreads out?

Thanks. Physics Forums rock!
 
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Thank you for a most interesting topic!
I recall that lightning charges go up and down between the surface and the thundercloud - quite a large distance - so the frequency is probably way too low for the high frequency skin effect.

But take a look at http://analogengineering.com/lightning/surface.html
It DOES go along the surface of the water. Looks like you could survive a strike by staying underwater. There is quite a good technical explanation there.
 
Thanks Delphi 51! Physics forums beat any textbook hands down.
 
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