2017 Aurora photo contest winning entry (years 8 to 10)
In this photograph, I created a ‘magic bag’ intended to contradict the audience’s expectations. One would think that poking holes through a plastic bag full of water will result in water spilling everywhere, right? Wrong. The science behind this thought provoking experiment is illustrated through everyday household materials including a plastic bag, water and coloured pencils. Most would assume that the plastic bag will behave the same way as a rubber ballon would; splitting instantly when punctured. However, the plastic bag is made out of a polymer, that is a durable barrier to moisture. Polymers are long chains of molecules that are flexible, which help form a temporary seal against the edge of the pencil, preventing the water from spilling out. Furthermore, when light travels from air to water it slows down, causing it to change direction slightly. This process is called refraction, and is occurring for many of the coloured pencils within the bag in the image. This experiment demonstrates how
indestructible plastic bags are, and their negative impacts on the environment when littered. This practical uses simple concepts, including the strength of plastic and light refraction, revealing how the complexity of science is everywhere.