Weird Science Weekly: Party prank physics reveals how beer tapping works

Scott Sutherland
Geekquinox
November 29, 2013

Weird science happens every day, all around us. This week, we have three of the weirdest examples, including the science behind 'beer tapping', how ice forms giant spinning discs in rivers, and 'religious ecstasy' may provide clues to how weather works...

Physicists show how that annoying 'beer tapping' prank works

Have you ever been a victim of that prank, where some joker at the party taps top of your beer bottle, and the whole thing foams up all over the place? Well, the loss of the beer might be inexcusable, but you can console yourself with this little tidbit, as physicists explain exactly why it happens.

It turns out that this is exactly the same way that you can get an instant frozen beer, as long as you keep the beer sealed and you cool it down in the freezer to below its actual freezing temperature. The beer will remain liquid as long as it isn't agitated, but the moment it gets a sharp rap, the bubbles form and the freezing occurs. Check out the Mythbusters team testing this one by clicking here.

[ Related: Weird Science Weekly: Five science videos to educate and entertain ]

Ice forms giant rotating circle in North Dakota river

The way that water flows can create some really neat patterns, but it's not often you get to see them so nicely, and on such a large scale, as when there's ice on the surface. Every once in awhile, especially where natural eddy currents form in the flow, you can get 'ice discs' — where a fairly solid mass of ice just sits in one part of the river and spins, forming a nearly perfect circle. These have been seen in other places in the world, but this particular one was along the Sheyenne River, in North Dakota.

The way this works is that the ice calves off of the shoreline, and the motion of the water flowing past gets the sheet of ice rotating. As it rotates, the edges of the sheet scrape against the ice near the shore and the edges eventually get worn down to a perfect circle. Unless the ice melts, or the whole river freezes across the top, or another ice flow comes down the river to disrupt it, it will just keep spinning there indefinitely.

[ Related: Weird Science Weekly: Fist bumps can help save lives ]

Scientist link Whirling Dervishes to the motions of weather

Sufi whirling, the dance that certain Turkish orders perform in order to reach 'religious ecstasy', doesn't cause or influence the weather, of course. However, researchers watching how the Dervishes' skirts whirl around have seen the same kind of patterns that cause storms to spin in particular directions, based on what hemishpere they're in.

The skirts, as they whirl around due to the Dervishes' constant spinning, are showing the Coriolis effect. This is the same effect that causes storms to deflect to the right as the move in the northern hemisphere and to the left as they move in the southern hemisphere. Since this effect on storms is due to the rotation of the Earth, it only works on very large scales (so it doesn't influence which direction the water swirls down your toilet or drain). However, for the Whirling Dervishes, their skirts are being influenced by a scaled-down version, to create waves and troughs in the material. By examining these motions, the researchers might be able to tell more about the patterns, what influences the effect, and apply it to the larger atmospheric scales.

[ More Geekquinox: Japan's new energy plan: A ring of solar panels around the moon's equator ]

Keep your eyes on the wonders of science, and if you spot anything particularly strange you'd like me to check out for next week, comment below or drop me a line on Twitter!

Geek out with the latest in science and weather.
Follow @ygeekquinox on Twitter!