How to Inflate the Best Bubbles
Have you ever met a street performer who blows bubbles at a show in a park or at a festival, and all the kids immediately jump, squeal and lose their minds? And then you try to recreate the same scene at home for your kids … and you fail. Don’t worry – not all is doomed yet. You just need science to be on your side. Here are some tips on how to inflate better quality bubbles.
It’s all about breathing
The component that most determines bubble formation is not a stick or even a solution, but the wind speed. As Popular Science reports , mathematicians recently discovered the optimal bubble-blowing formula:
U = √ (5.6 x gamma / rho * R), where U is the wind speed, gamma is the coefficient of surface tension between the two fluids involved, rho is the density of the fluid you are blowing in, and R is the radius of the bubble wand.
If your reaction to it is like mine – a blank stare – you can think of it this way: For a bubble wand with a radius of 1 centimeter, the optimal wind speed is about 8 miles per hour. (For context, as PopSci notes, the average human sneezing speed is about 39 miles per hour.) Of course, you can’t actually measure how fast you blow without fancy tools, so just try blowing at different speeds to see. what works. …
But the decision matters too
For strong bubbles with a beautiful rainbow sheen, use liquid dish soap. These types of soaps are detergents, which means they contain surfactants, and surfactants are important because they lower the surface tension of the water. Less surface tension creates a smoother layer of water, making it harder for the bubble to burst. Adding a stabilizer like white sugar or corn syrup adds strength as well.
Professional bubble artists such as Melody Youngadjust their solutions based on the environment they are in: in hot, dry atmospheres, bubbles burst faster, as in thin air at high altitudes.
Here is a proven formula used at the shows at the Exploratorium in San Francisco:
- 2/3 cup Dawn dishwashing soap
- 1 gallon of water
- 2-3 tablespoons of glycerin (available at drugstores or chemical stores).
Experiment with different wands
A wand is the least important ingredient for creating bubbles – you can use one that was in the bubble solution, a string such as baking twine to create huge bubbles , a tube cleaner shaped like a circle, or your index and thumb shaped like A. See how Jan demonstrates the finger technique here:
Soak your entire hand in the solution, make an “OK” sign, turn over to one side and start blowing. After you create a bubble, she says, “All you have to do is close this hole and trap this air.” Give it a try and watch your kids explode. Thank you science!