Introduction to Rheology
November 08, 2021
I’m always very excited to see that the Soft Matter Kitchen continues to reach broader audiences. Because of this, I felt that it would be important to provide a concise and basic introduction to the field of rheology. The video below is a version of a demonstration that I have used to introduce people to the idea of soft, complex materials, and the types of things that rheologists might study.
The concepts of simple solid and fluid materials are often defined by whether or not they have their own shape, respectively. However, there are many materials that do not cleanly fit these definitions. In this video, I use two common foods, honey and whipped cream, and show that considering the question of, "which is more viscous", leads us to a surprising answer. This demonstration introduces the idea of complex materials which have different behaviors depending on how we push on them and thus seem to exist somewhere in-between the concepts of solid and fluid.
As a note, the variety of honey used in this demonstration is an example of a simple fluid, and is distinctly different from a previous video entry on thixotropic Manuka honey.