In the video above, a chain of 8,000 beads is stuffed into a beaker. They're not unlike the itchy metal necklaces goth kids can purchase at Hot Topic. Now look at what happens when you toss one end into the air. The result is jaw-dropping, in a slinky, snake-like sort of way. Physics!
As for why the chain travels along a single pathway, suspended in midair, it's kind of like a "tug-of-war," explains BBC's Steve Mould. You have the weight of the beads inside the beaker at odds with the other end falling fast to the ground.
"So you've got the inner chain traveling up, but it wants to change so it's traveling down, but it can't do that in an instant, because that would require infinite force," says Mould. "Instead what it does is it changes direction slowly over the course of a loop, so that's why it almost has to be a loop, because it needs that time and it needs that space to change directions."
In the video above, they try all sorts of variations with different kinks and loops — a great trick to try if you just so happen to have 50-meters worth of metal beads lying around the house.