Does a falling Slinky float in mid-air?
Modeling a falling slinky
When you drop a hanging Slinky, its bottom end floats in mid-air for a moment. Physicists explain why.
Hold a Slinky by the top, let it stretch down, then let go. The two physicists modelled the toy as a chain of springs to explain what slow-motion videos show.
The top collapses downwards, but the bottom stays perfectly still until the squashed-up wave of coils reaches it, because it simply hasn’t got the news yet. A toy that seems to briefly ignore gravity.
The bottom of the Slinky is the last to hear about anything.