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How does quicksand work?


If you're planning to visit the beach this summer, you may be worried about encountering quicksand. You may have heard that humans can get sucked up by quicksand. Well, the good news is that this isn’t true! But before we go into that, let’s learn a little bit about quicksand.

Quicksand develops when sand or earth becomes overly saturated with water. It usually occurs at the mouths of large rivers, or along stretches of streams, beaches or marshes, where sand mixes with water. Because it contains so much water, quicksand cannot support much weight. So when a person or object is placed on the surface, it sinks.

Quicksand can function as either a liquid or a solid. There's a scientific term for this kind of substance: non-Newtonian fluid! When force is applied to quicksand, it becomes a liquid. This is why when a person steps on it, they will begin to sink. Once the force stops, quicksand becomes solid again, which causes the person to become stuck. But it doesn't swallow up humans all the way. Just as we float in water, people will usually only get stuck up to the waist in quicksand. Of course, it's still important to know how to get out! The key to escaping quicksand is to distribute your weight as evenly as possible.

If you would like to see firsthand how quicksand works, you can try making it at home! Oobleck is a substance with properties very similar to quicksand. You can make oobleck out of cornstarch and water. There are many recipes online, or you can find one in the recommended reads below. Once you've made your oobleck, try placing a toy on the surface and see what happens. How quickly does it sink? Does it get stuck? How difficult is it to get it free?

Anyway, don’t worry too much about quicksand at the beach, as your chances of running into it are rare. So relax and have a good time - while social distancing!

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