The set of images show a non-newtonian fluid under variable stress. In non-newtonian fluids, viscosity varies with the stress. This means that the fluid behaves differently in case it is under low stress conditions or high stress conditions. In particular, in the set of images, a hand touching a non-newtonian fluid is shown. It is possible to see that, at the beginning, the fluid is under high stress conditions (because of the punch to the fluid) and it behaves like a solid. In the last images, the fluid is subject to a lower stress since the hand is entering slowly the fluid: in these last images, the fluid behaves as a fluid (in a while the hand is completely submerged).
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<span class="int-own-work" lang="en">Own work</span>