Category: Forces

🎄 Watch a chain of beads flow upwards and out of a glass – this is surely the most fun you can have with your Christmas decorations! Every year, our children look forward to this moment almost as much as the big day itself!

🎄 You’ll notice that the chain arcs over the rim of the glass, going upwards, before being pulled downwards. So how does it work? This is a cool physics problem to ponder! It happens because the chain acts like lots of connected little rods. When you pick up one end of a rod, that end of the rod goes up, and the other end tries to go down. However, if the downward force is stopped by the pile of beads below it, there is a small kickback, and the rod is pushed upwards. That upwards thrust at each link in the chain is what makes the chain rise. This is an easy activity to try for yourself at home! Just make sure that you feed the chain gradually into the glass from one end so that it doesn’t get into a tangle when it’s flowing out. You could experiment with letting the chain fall from different heights (for example by standing on a step compared to sitting down) to see if that makes a difference to the height that the chain reaches.

🎄 Have you ever seen a chain fountain in action before? Watch a Mould effect video, otherwise known as a chain fountain phenomenon video here! It’s the perfect simple science experiment to try at home!