and hot chocolate mix.
first, tap the rim of your mug several times with your spoon and listen to the pitch (how high or low the sound is). did it change while you were tapping? of course not!
next pour some hot milk or water into the mug and tap again. any change? not likely. try stirring the milk and tapping while the milk is still swirling. you probably won’t hear any changes in the pitch here either.
now for the fun part! pour a packet of hot chocolate (or a tablespoon or two) into the mug of hot milk. give it a couple of quick stirs and start tapping again. what do 