Underwater "experiments"

[Pillow]

When we find 32 and 48 oz plastic soft drink cups on the bottom of out local lake, we turn them upside down and fill them with air. They rise towards the surface and the air expands and spill out of the opening (which is on the down side), The air spilling out makes it look like a rocket as it rises.

 

[Rick Inman]

A guy I dive with regularly loves to play with air under pressure. He actually has a LP hose with an air inflater on the end - like the kind that you full your car tires with. He is always taking down different containers and filling them at depth. He likes to tie a string to them and swim them about 10 feet above him and watch what happened as we ascend. He wears extra weight for just this reason.
One of his favorites is to fill a 2 ltr bottle at 100' and bring it to the surface. I have seen him do this several times, and it never explodes. But, man, the bottle is tight! He takes them to work and has people feel them. Really!

 

[SueMermaid]

I took a styro cup to 80' with me at Dutch Springs. It got quite a bit smaller and stayed that way after I brought it up.
I tried to bring a marshmallow in a baggie with me on the same dive, but the bag was not sealed well enough and all I got was marshmallow moosh.

 

[hecker-the-wrecker]

Rick, see if your buddy with the inflator could fill a basketball!! I think you would have to deflate it to get it down there, but after you fill it up, if you left the filler needle in it, it might act like a rocket as it gets closer to the surface.or without the needle, it might just explode, (way cool)!!!

 

[MSilvia]

I haven't tried it, but I hear that if you take a carbonated drink (root beer) down to about 100', shake it up, and open it, the drink will just stay put in the can, and you can drink it easily.

 

[Bob3]

When you have a can of "carbonated beverage" at depth, the can will inhale when opened, the liquid still "tastes" fizzy though, probably from the CO2 in solution hitting the tongue.

 

[PhotoTJ]

Not so much an experiment as a practical joke; duct tape a bag of frozen peas to a buddies tank, and cut a hole at depth. He will think he's being attacked by every fish in the sea.

 

[crpntr133]

Not so much an experiment as a practical joke; duct tape a bag of frozen peas to a buddies tank, and cut a hole at depth. He will think he's being attacked by every fish in the sea.

Cheese whiz works real well for this and you can do it over and over again. BTW the can will rocket to the surface even after it is "empty".