The Soma Cube is a solid dissection puzzle that made it into my collection.
There are many solid dissection puzzles out there. A solid dissection puzzle is a 3D puzzle where the goal is to arrange the pieces or blocks so that they form a certain 3D shape. In the case of the Soma cube, the goal is to make a solid cube out of seven smaller pieces. Piet Hein, a Danish mathematician created the Soma Cube in 1936.
These pieces, though, have a special property. They consist of either three or four unit cubes that are joined at their faces such that at least one inside corner is formed. In the case of three cubes, there is only one possible arrangement (think of an V-shape). In the case of four cubes, there are six possible arrangements. This includes two of which are mirror images of each other.
Overall, there are 240 different ways of solving the Soma cube, excluding reflections and rotations. But here’s the interesting thing: in each of the 240 solutions, there is only one place for that T-piece. The reason for this is fairly clever, and I’ll leave you to think about it. Here’s a hint: consider the possible places the T-piece can fit and then look at the number of corners available on the cube and the remaining pieces.
Simple puzzles like the Soma cube can exhibit some very interesting properties. This is why I added it to my collection. I’m always on the lookout for oddities that are diffierent. This cube fits the bill perfectly.