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How Lightning Works

2015 December 21. Monday.

You’ve all seen it! Kablooey! But do you know how lightning works?

what lightning is

When you rub two socks together sometimes you get a small zap. The rubbing pulls electrons off of one sock and into the other. After a while there is a large enough negative charge on one sock for it to be worth the energy required to travel through the air and hit your hand.

Clouds are the same thing on a massive scale. Big floating masses rub up on each other and make a charge difference. Since clouds are really far from the ground, it takes a lot of energy for electricity to travel through that air. Hence the buildup and discharge are both very large.

How large? At least enough to break a tree:

how lightning decides who to kill

Most naturally occuring solids have far less resistance than air, so lightning prefers going through 20 extra feet of tree to going through 1 more foot of air.

So here is method from xkcd to find where lighting strikes:

This is where the 60-meter sphere comes in. It’s a way to imagine what spots might be the first thing the leader senses—the places it might jump to in its next (final) step.

To figure out where lightning is likely to hit, you roll the imaginary 60-meter sphere across the landscape (for safety reasons, do not use a real sphere). This sphere climbs up over trees and buildings without passing through anything (or rolling it up). Places the surface makes contact—treetops, fenceposts, and golfers in fields—are potential lightning targets.

be safe no matter where you stand

Alternatively, if you where a solid welded metal suit, then lightning will go through the suit instead of going through you.

MinuteEarth explains:


I am not a lightning expert. Be struck at your own risk. Occasionally people do die from sky sparks.

Public Domain Dedication.