1)Mix one cup with the sugar water and other one with the fresh water. Take a sip of the sugar water and swish it around within your mouth for different seconds without swallowing it; progressively, it must tasteless sweet. After taking it (or spitting it back into the cup), taste from cup consisting of the fresh water. Specify whether the taste of fresh water surprised you or not? Explain how?
2) Rub your index fingers over a piece of very coarse sandpaper gently, a few times and rate its coarseness on the scale from 1 (very soft) to the 7 (very coarse). After the minute or two, rub same finger over the paper and again rate its coarseness. Explain if your perception of coarseness change or not? Explain how?