When air moves, the air pressure decreases. This creates a lower air pressure pocket right between the cans relative to the surrounding air. Because higher pressure pushes, the cans clink together. Just remember – whenever there’s a difference in pressure, the higher pressure pushes.

You will need about 25 straws and two empty soda cans or other lightweight containers

### 4 Responses to “Soda Can Trick”

1. At seal level, the pressure is 14.7 psi (which is like having 10 meters of water pressing down on you due to the atmosphere we live in), but when you climb higher in the atmosphere, you have less air above you. At 10,000 feet, it’s 10.3 psi instead of 14.7 at sea level. Under normal conditions, you’d only see about half of a psi fluctuation with weather changes.

2. Kelly Gorecki says:

Is 14.7 psi the pressure of air at higher elevations?
If you are in a high pressure system or a low pressure system, is the air pressure still 14.7 psi?

3. MaryAnna Cashmore says:

Clarifying: The toilet paper rolls need to be lying down parallel on the tabletop, with about an inch between them. Hold the straw parallel to the rolls, exactly between them, so that the far end of the straw is between the centers of the nearest ends of the rolls.

Front view: ( )-o-( )

Top view:
(((((((((((((((
———–>
(((((((((((((((

4. MaryAnna Cashmore says:

We did this with one straw and two empty toilet paper rolls. We placed the TP rolls on the table about an inch apart, then used the straw to blow into the space exactly between the two rolls. Presto! They rolled together. Good ol’ Bernoulli. I’m sharing this just in case anyone else used up all their empty soda cans on the really cool squashed can experiment earlier. 🙂