We've all been there. A balloon pops unexpectedly, and our reaction is to leap out of our skins.
But once we all get past our collective fear of loud noises, and the devastation that is a popped balloon, there are actually some interesting scientific questions that need answering.
In a new study published in Physical Review Letters researchers found that the amount of pressure inside a balloon directly affects how the balloon pops. The authors filmed their experiments with a high-speed camera, allowing them to see how a balloon pops in very slow motion.
When you inflate a balloon, you apply stress, or tension, to the material part of the balloon as it inflates, stretching it over the air that you're blowing into it. If the tension is low (for example, if the balloon hasn't been inflated all the way) the balloon pops cleanly, with one long crack:
But if the balloon is filled with a lot of air the stress gets higher, and scientists found this generates a very different result. In that case, the combination of a sharp object with the aforementioned balloon, looks a little something like this:
Or, from another perspective:
Cool, right? The balloon with the higher stress fractures into many different pieces. While that might seem like no more than a party trick, New Scientist reports that the researchers hope to apply their discovery to more brittle objects like glass and metal, to potentially create materials that are less likely to shatter when a sudden shock is applied.
In the meantime, you can try the balloon experiment at home. Even if you don't have a high-speed camera, you can watch the science happening in real time.