Four Marble Puzzle https://main.physicsfunstore.com/p/main.html Physics brain teaser- move all four marbles to their corner locations simultaneously. Each slot slopes down towards the center such that the marbles tend to stay at the center- so, how would one get them to roll outward at the same time? The solution to this puzzle (like others featured here) relies on some fun basic physics principles. Answer below and solution in comments. A beautiful and well-made puzzle from Creative Crafthouse.

Floating Hourglass Puzzle: famous physics puzzle- why does the hourglass not start rising right away? The glass only ascends after about half of the sand has transferred to the lower bulb. The hourglass is a normal glass timer, it is submersed in plain water, and the main tube has an inner diameter which is at least 2mm larger than the diameter of the glass. A simple physics property of the hourglass changes and explains this behavior. I'll post the answer in a day or so. Follow this link for in