Mixing is everywhere in our everyday life from baking a birthday cake in the kitchen to making a cup of coffee in the morning. Have you wondered how all these mixings work? What is the best way of performing mixing? From the perspective of physics, mixing is a repeated process of stretching and folding. Think about mixing milk to the coffee. You need a spoon to stir the coffee, but what does stirring really mean? When you stir, you create flows and currents in the fluid, which stretches the fluid. Then, the fluid get chaotic, which folds the fluid onto itself over and over on a tiny scale. Hence, while you were stirring the coffee to blend it with the milk, what you actually do is to stretch and fold the coffee-milk fluid until the fluid is uniform.
In this activity, we will demonstrate the essence of mixing through an activity of blending a couple of colored dough balls. You will learn how blending these balls can be accomplished by simply following the fundamental actions of mixing processes: repeated stretching and folding.
We want to see your work! Take a photo or video and upload it here to our special TouchTomorrow virtual bulletin board!
Activity contribution: Teagan E. Bate and Kun-Ta Wu designed the activity. Teagn E. Bate prepared the activity and instructional video. Kun-Ta Wu supervised the activity development.
Acknowledgement: Kun-Ta Wu acknowledges the support from National Science Foundation (CBET-2045621)
Teagan Bate is a physics PhD student. He studies microtubule-kinesin based active fluids in assistant professor Kun-Ta Wu’s laboratory. In addition to his research, he has mentored undergraduate and high school students in doing their own research and has worked as a laboratory instructor for the physics courses. He is also an avid rock climber, hiker, paddler, woodworker, and amateur forest ecologist!
Learn more about Professor Kun-Ta Wu and Wu Lab.
Facebook
Twitter
Instagram