Name one person who doesn’t enjoy bubbles. They are simple, beautiful, and fun. We learn to associate bubbles with whimsy and delight from an early age, but if a physicist had explained that bubbles’ mysterious cousin, the “antibubble,” was something we could be playing with at home, who knows which chemical orb would have won out.
In the latest video from YouTube and PBS’ Physics Girl, our host Dianna first demonstrates a classic visualization of surface tension. Using milk, food coloring, and some soap, surface tension will force apart the colored surface making a beautiful dairy canvas. Try it, and then flick the milk a little bit. You might see some odd droplets roll across the surface. Those are antibubbles.
The bubbles you blew as a kid (or an adult, that’s cool) are basically gas enveloped in a thin film of liquid. Antibubbles, on the other wand, are liquids encased in a layer of gas. Because liquid is more dense than gas, antibubbles tend to sink or float, rather than rise into the air. However, antibubbles don’t have the same molecular structure that typical bubbles do, as the video points out. That makes them much more likely to pop, but I’d argue that watching these tiny oddities pop is more interesting anyway.
If you want to make antibubbles at home, all you need is some soap, water, a squirt bottle, and some food coloring. Physics Girl explains the finer details — you’ll have to find the ultimate mixture and technique yourself.
What do you think? Are antibubbles better than traditional bubbles, or just a forgettable byproduct of fluid dynamics? Let us know in the comments below.
Images: Physics Girl