Is Sucking the Opposite of Blowing? The Reverse Sprinkler Problem
by Mark Frauenfelder from on (#42A7C)
The Action Lab Man demonstrates the physics of flowing air in several fun ways to explore Richard Feynman's "reverse sprinkler problem." A hypothetical reverse sprinkler (the sort that spins) is one that sucks in the fluid that surrounds it. Which direction does it turn? This question has led to lively debate among physics enthusiasts.
This question is also posed in a great physics puzzle book, called Thinking Physics.