Wow ...

[sunny-dave]

... I have no idea about the physics behind this - but it makes me go 'WOW'
.

https://www.youtube.com/watch?v=uENITui5_jU

[mrs_overall]

Fascinating!

[gness]

That is just beautiful...when you've sussed it out will you come and make one on my patio please.......the reverse one would be great...especially when guests have had a glass or two.....x

[rockyracoon]

That's very good, particularly the reverse one.

[Svejk]

That's quite weird, alright. Can't think of a caption though.

[tonyav]

Blimey thats great. gawd, gotta go for a wee.

[Lie-in King]

Brilliant, thanks Dave! :-))

[DTCwordfan]

everything has a natural frequency and when you have two that match up, then you can get this oscillation effect. It's why soldiers are made to break rank when marching over a bridge......

[Canary42]

WOW - Wonderfully Orchestrated Water

[jim360]

As a professional physicist this works by magic.

[naomi24]

Excellent!