Rehbinder effect demonstration - GIF

Rehbinder effect demonstration.

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Previously:

https://www.homemadetools.net/forum/...240#post203981
https://www.homemadetools.net/forum/...458#post200680
https://www.homemadetools.net/forum/...814#post202245
https://www.homemadetools.net/forum/...512#post200984
https://www.homemadetools.net/forum/...538#post193166

I don't have enough unnecessary cups to experiment with, but I expect the cup is full of water when the nail is hammered through it? Quite a bit of what looks like chop on the water when he's hammering, and water is non-compressible, but transmits force. INTERESTING demonstration.

Bill

I seem to remember a demonstration where glass was cut with scissors under water.

Quote:

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Originally Posted by mklotz

I seem to remember a demonstration where glass was cut with scissors under water.

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Huh. Well would you look at that.

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

From wiki:

The Rehbinder effect in physics is the reduction in the hardness and ductility of a material, particularly metals, by a surfactant film.

A proposed explanation for this effect is the disruption of surface oxide films, and the reduction of surface energy by surfactants.

The effect is of particular importance in machining, as lubricants reduce cutting forces.

Quote:

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Originally Posted by mklotz

I seem to remember a demonstration where glass was cut with scissors under water.

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Apparently my memory was accurate...

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