This puzzle was produced in the 1990s, sometimes found on eBay (currently two avialable):
From eBay: SEARCH NOW: Magic Sand Wand Puzzle
Wikipedia has a good introduction to the possible mechanisms of the Brazil nut effect
Magic Sand Wand Puzzle: this week’s physics brain teaser- move the steel ball through the sand to the other end of the tube. Amazingly it can be done in less than 6 seconds! Hint: spinning won’t help this time. The solution to this vintage puzzle relies on some interesting physics concerning granular convection. Answer below and swipe to reveal solution.
Get this puzzle here:
From Amazon: BUY NOW: Atomic Cherry Puzzle
Elastic Equilibrium Puzzle: six spheres held together by three plastic springs. When assembled each sphere exerts the same force on its four neighboring spheres, producing this equilibrium state only if all six spheres are used to balance all the forces. A fun configuration to analyze in a 1st year physics course- the Atomic Cherry by Brainwright puzzles.
The Rhoma Cube is a vintage item and can sometimes be found on eBay:
From eBay: Search NOW: Rhoma and Soma Puzzles
Soma Cubes are available in a wide viariety:
From Amazon: BUY NOW: Soma Cube
From Etsy: BUY NOW: Soma Cube
SOMA and RHOMA Puzzles: Replace every cube in the Soma puzzle with a rhombohedron to create the Rhoma puzzle- where the seven slanted pieces now make a larger rhombohedron. Here I’ve painted the corresponding Soma and Rhoma pieces to match on these sister puzzles that share identical edge lengths. While there are 240 ways to make the larger cube from the 7 Soma pieces, there is only one solution for the 7 Rhoma pieces. The original Soma Cube is a math toy has an interesting connection to physics- invented by Danish scientist and artist Piet Hein who claimed that this puzzle idea came to him as he was listening to a lecture on Quantum Mechanics by Werner Heisenberg in 1933. The seven pieces are all the ways 3 or 4 cubes can be joined, such that each piece has at least one inside corner.