What is Isotropy and Thixotropy and how does it effect our everyday lives???

Question

What is Isotropy and Thixotropy and how does it effect our everyday lives???

Answer 1

When you run on the wet beach sand.. or whack a ketchup bottle to get it moving, that's isotropy and thixotropy

Details:

Isotropy is the property of a fluid to become firm when agitated. This is what you're experiencing with the cornstarch and water. You can also see this while walking on wet sand at a beach. The sand firms up below your feet as you first touch the sand and then becomes more fluid, as your feet sink into the sand, just a moment later. If you run over the sand, the sand will feel very firm. If you walk slowly, your feet will sink below the surface with every step.

Thixotropy is the opposite of isotropy in that the fluid mixture becomes more fluid (less firm) as it is agitated. An example of this is where you strike the end of a ketchup bottle to get ketchup to come out of the bottle. The striking force temporarily causes the ketchup become 'runny' and it flows more easily from the bottle (and on to your new clothes - white ones). Another example is the infamous "quicksand". If you thrash around in the quicksand, you will sink "quicker" because all that wiggling causes the sand to liquify.