Saturday, December 28, 2019

Reflections on repeating the liquid-stack demo - now with some additional twists & toys

I repeated the three liquid stack demonstration described in an earlier post (

Based on doing it again, here are some pointers:
(1) It is good to put the honey in first because it takes such a long time to get into the bottle.
(2) The best thing for each layer is putting the coins on the bottom, followed by pasta noodles at the honey water interface, blueberries at the oil-water interface, and, finally, cork at the very top.

There are several other toys that can be coupled with this demonstration.

(A) The Ooze tube ( can act as a timer to indicate resistance to flow very well in the honey oil situation.

(B) Moreover, one can use a hand boiler (, which has alcohol, to demonstrate other aspects of liquids such as boiling; this isn't evident in the three liquid stack.

(C) Finally, one could perform a circuit demonstration, using a "Sci-Fi Sensor Stick" (
This is a lot of fun and shows flow in another type of liquid -- in the sense of electrons flowing through a circuit, which is somewhat connected to the flow of liquids.

See also