# I Compressing a bottle with water - initial velocity of water

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1. Jul 20, 2017

### ChessEnthusiast

Imagine that we have a closed plastic bottle filled with water and then we punch a hole with area A in its cap. How can I find the initial velocity the water will he "fired" with if we squeeze the bottle applying stress S?
Assume that we know all about the bottle (moduli, change in volume etc.
I guess that the Pascal's law is not enough here and it's got a lot to do with the material the bottle is made of.

2. Jul 21, 2017

### .Scott

The exterior pressure will be 1 atmosphere. So you need to know the interior pressure and the diameter of the hole you cut.
Here is a link to a calculator:
http://www.tlv.com/global/TI/calculator/water-flow-rate-through-orifice.html

You do need to determine the pressure of the fluid in the bottle.

Perhaps the easiest way of determining this is to perform the experiment. When you squeeze the bottle, hold it horizontally 1 meter above the floor. The fluid will eject horizontally and the fall to the floor. The height above the floor will give you about a 0.31 second delay. The distance that the water moves horizontally before hitting the floor will tell you how far it traveled in that amount of time. It would be a rough approximation.