Why Does Toilet Water Splash Back Up?

[wally_moot]

Now although this is silly and quite crude (You have been warned), it is a legitimate physics question. I was sitting on the toilet a few days ago and I got some splash back. I started thinking about elastic collisions and how no matter what, nothing is perfectly elastic (correct?). Why would the water come all the way back up to my... you know what and not just my cheeks. If water doesn't observe the behavior of an elastic collision, it must be a mass issue. Maybe the mass of water that gets splashed back up is less than the amount of the impacting mass?

 

[Simon Bridge]

You can experiment by dropping different weights (and different shapes) into a bowl of water and see which splashes the highest.

In terms of energy, even with losses, a small amount of water can be shoved quite high while a lot of water won't.

The size and shape of the splash tends to depend on the shape of the container, the shape of the object landing in it, and the mass of the object.

How it falls is also important - you were not in a position to tell if your spoor dropped straight or did a bit of a rotation on the way down I suppose?

 

[A.T.]

This might help

https://www.youtube.com/watch?v=-XNDM4eAn1U

 

[Simon Bridge]

That's great: good find!