Instead of people, he used aluminium beads which have the same density as a human. He put them on top of the sand and then, to simulate the flailing of a panicking human, he shook the whole model and waited to see what happened.
The answer was no. At first they sunk a little, but as the sand gradually began to mix with water again, the buoyancy of the mixture increases and they floated back up to the top. Bonn and his team tried placing all sorts of objects on his lab-made quicksand. If they were of density equivalent to a human they did sink, but never completely, only half way.
This is really when quicksand can be dangerous. The quicksand effect means that falling into a silo full of grain can often be fatal Credit: Getty Images. They tested samples from the shores of a lagoon in north eastern Brazil. They found that bacteria formed a crust on the top of the soil, giving the impression of a stable surface, but when stepped on the surface collapsed. Dry quicksand, however, is another matter entirely.
This article has been viewed , times. Learn more You're hiking alone in the wilderness, lost in your thoughts, when suddenly you find yourself trapped in quicksand and sinking fast. Certain muddy death? Not quite. While quicksand isn't nearly as dangerous as it looks in the movies, it is a real phenomenon. Here's what to do if you find yourself with that sinking feeling.
To get out of quicksand, start by taking a few deep breaths to calm down since panicking will make you sink faster. Then, bend your body backward so you're lying on your back on top of the quicksand, and carefully work your legs out of the quicksand until they're no longer stuck.
Next, use your arms to propel yourself to the edge of the quicksand like you would if you were swimming. Finally, once you reach the edge, roll your body onto solid ground. For more tips, like how to recognize and avoid quicksand, keep reading! Did this summary help you? Yes No. Log in Social login does not work in incognito and private browsers.
Please log in with your username or email to continue. No account yet? Create an account. Edit this Article. We use cookies to make wikiHow great. By using our site, you agree to our cookie policy. Cookie Settings. Learn why people trust wikiHow. Download Article Explore this Article parts. Tips and Warnings. Things You'll Need. Related Articles. Article Summary. Part 1. Drop everything. If you step into quicksand and you're wearing a backpack or carrying something heavy, immediately take off your backpack or drop what you're carrying.
Because your body is less dense than quicksand, you can't fully sink unless you panic and struggle too much or you're weighed down by something heavy. Shoes, especially those with flat, inflexible soles many boots, for example create suction as you try to pull them out of quicksand. If you know ahead of time that you are highly likely to encounter quicksand, change out of your boots and either go barefoot or wear shoes that you can pull your feet out of easily.
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Updated December 04, Key Takeaways: Quicksand Quicksand is a non-Newtonian fluid made of sand mixed with water or air. It changes its viscosity in response to stress or vibration, allowing you to sink, but making it hard to escape. You can only sink into quicksand up to your waist. Really, the only way to drown from the quicksand is to fall into it head first or face first. But a person moving around in quicksand will never go all the way under.
The reason is that humans just aren't dense enough. Quicksand has a density of about 2 grams per milliliter. But human density is only about 1 gram per milliliter. At that level of density, sinking in quicksand is impossible.
You would descend about up to your waist, but you'd go no further. Even objects with a higher density than quicksand will float on it—until they move. Aluminum, for example, has a density of about 2. But a piece of aluminum will float on top of quicksand until motion causes the sand to liquefy. During their study, researchers placed an aluminum bead on top of a container of laboratory-created quicksand. At rest, the bead remained on the surface, despite aluminum's higher density.
But then scientists started shaking the container. When they shook it only a little, the bead stayed floating on top. But when they shook the container a bit harder, the ball descended to the bottom. But if quicksand becomes less viscous as you struggle, why is it so difficult to escape? The reason, explain the study's authors, is that after its initial liquefaction, quicksand's apparent viscosity thickness or flow resistance increases. The increase is due to the formation of sand sediment, which has a very high viscosity.
It's the difficulty of moving this dense sand that causes the problem. Water has to be introduced into the sand sediment to loosen it, and this requires considerable amounts of force.
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