Cutting Water by Kyle Patrick Keane
2nd Place - Contrived Category
School: Glenbard West
Teacher: Bruce Medic
Bubbles played around with are not just made of water. They usually contains a type of soap, or more specific, a surfactant. Surfactants are substances that lower the surface tension of liquids, making them weaker and thus more flexible, originally for the purpose of being able to clean better. A lower surface tension leads to how bubbles are made, as water’s normally strong, rigid surface tension is lowered by surfactants such as dish soap, allowing for the film to encase air. Furthermore, the molecular structure of the water is naturally attractive to itself due to the polarity of water. Scissors when wet can “cut across” a bubble, yet not pop it because the water will be attracted to itself instead of steel of the scissors. The bubble wall will mold around the protrusion rather than creating a hole. Popping only occurs when an unbalance of the atmospheric pressure or the pressure within the bubble exceed the force that the walls can withstand, often as a result of holes. This allows the trapped gas to escape, levying an unbalanced force on the bubble, leading to its inward collapse. Bubbles also pop due to evaporation of the water. Nevertheless, evaporation leads to rifts of the spherical walls, resulting in the inward collapse of the bubble.
