99 bottles of…oops January 28, 2014Posted by mareserinitatis in education, physics, science.
Tags: boy scouts, pascal's law, physics, science, Scientists, teaching, video
Yesterday, I was helping guide some cub scouts (specifically webelos) through their scientist achievement. One of the things we had to discuss was Pascal’s law. Unfortunately, the instruction set on this was pretty limited: read and discuss. That, to me, means they likely wouldn’t understand it at all, so I felt like a demo was in order.
I decided to demonstrate the pressure change in a beer bottle. The concept is simple: fill an empty bottle with a non-compressible fluid (so water works, air won’t) and tap on the open end with a rubber mallet or even your hand. Of course, you want to do this over a bucket because the sudden change in pressure causes the bottle to break at the weakest point, usually the seam along the bottom, and spill it’s contents.
I did this demo for the first time in front of the kids. (I had ONE bottle of beer. No, I didn’t imbibe in front of them…I used it to bake bread.) It worked like a charm. If I didn’t trust physics so much, I wouldn’t have been okay trying it cold like that.
If you don’t have a beer bottle handy and would like to see this demo, there’s a good video on YouTube: