Comment by jeffparsons
Comment by jeffparsons 5 days ago
How about this one:
Assume an arbitrarily high coefficient of friction between all surfaces. Can you stack the blocks on the table such that at least one block is wholly below the top of the table?
I think I have an answer to this, but I've only worked it through in my head, so there's a good chance I'm wrong!
If the blocks are thin enough, I think it's possible. Stack three blocks. Position the left edge of the stack on the edge of the table, so it's hanging downward at a slight angle, and stack enough blocks on top that it holds. Now slide the middle block 2/3 of the way out. The friction should still hold.
I think it's also possible for other shapes, all the way up to square blocks. But you need to build a bunch of nested "clamp" arrangements, instead of just one.