Rainbows don’t work the way you think they work [video]

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I hadn’t really thought about rainbows since learning the ‘wrong’ explanation in school but this video shows that it’s obviously wrong. Not mentioned is interference which I think leads to supernumerary rainbows.

I didn't know that, but it may be interesting for other users too. The double rainbow are very different of the supernumerary rainbows:

The double rainbow is caused by light that takes a different path inside the drops. (I've seen a few of them.) https://en.wikipedia.org/wiki/Rainbow#Double_rainbows

The supernumerary rainbows are caused by interference when the drops are too small, so they are more common with fog. (I never had seen them :( .) https://en.wikipedia.org/wiki/Rainbow#Supernumerary_rainbows

… and twinned rainbows are caused by larger droplets being flattened by air resistance and so refracting light at a different angle.

If you’re interested in this sort of phenomenon, check out Light and Colour in the Outdoors which explains a lot of them with various amateur experiments one can do with e.g. two razor blades or a long tube or whatever to visualise them.

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