These Hydrophobic Steel Balls Cut Right Through Water

These Hydrophobic Steel Balls Cut Right Through Water

Science is pretty dang cool sometimes, as human ingenuity continues to create new and innovative ways of dealing with the world around us. And sometimes it even involves balls so we can write about it here. Case in point: steel balls designed to cut seamlessly through water due to their hydrophobic nature.

As any chef can tell you, oil and water don’t mix. Water molecules interact with something called a “no-slip condition.” Liquid molecules adhere better to solid materials than other liquids, but in these hydrophobic balls they work in the other direction, surrounding it with a pocket of gas to reduce that adhesion. The spherical shape entrains the gas behind it, creating a projectile. That’s harder than it looks, though.

The trick is using a ball coated with a hydrophobic substance, in this case lycopodium, a substance made from mold spores that, when wet, covers things that pass through it and makes them hydrophobic. In the experiment, it’s put on the surface of the water and a steel ball is shot through it. You can see that when it drops it loses virtually no momentum. Here’s a pretty interesting video describing what’s happening.

What the real-world applications of this are have yet to be determined, but it’s cool to see.

Read more at Interesting Engineering.