Question: What happenes in the sky when it thunders and lightning?

Carol White answered on 6 Jul 2012:

Hey weirdboblet!

Thunderstorms are all about electrical charges: lightning is a sudden bolt of electricity that flows from a cloud to the Earth (normal “fork” lightning), or sometimes between two clouds (the much more awesome “sheet” lightning).

Clouds can become electrically or statically charged because as particles move inside them they bump into each other and strip electrons away from each other. You get the same thing happening when you rub a balloon on a fluffy jumper or on your head!

This charge grows bigger and bigger, and separates out so you get a positive top bit of the coud, and a negatively charged bottom side. When this difference is too big, the charges are evened out by an electric current…. a lightning bolt!

There’s a lot of energy in a lightning bolt, so it can electrocute people and things and even cause fires….

At the same time as the lightening bolt you get a thunder clap/roar (people say different things!) but you hear it a bit later because sound travels much slower than light.

Then it strikes, lightning heats the air around it (apparently to up to 30000 °C – that’s nearly 5 times hotter than the sun’s surface!) and the air expands in a massive explosion… thunder the bang of the explosion!

Thanks for sticking in the competition with us, it’s got a bit lonely now ther’es only two of us…

*** home/playground science experiment: make some thunder!
Blow up a paper bag and pop it… I’m sure you’ve tried this already! The loud bang is made pretty much the same way as thunder… cool!