"Physicists Crack the Mystery of the Reversed Sprinkler"

After 141 years of speculation, a team of researchers at New York University has successfully demonstrated and explained the behavior of a reverse sprinkler underwater, a question that has puzzled physicists since the 1880s. Using high-resolution, high-speed cameras and dyeing the water, the team found that the reverse sprinkler does rotate in the opposite direction to a regular sprinkler, albeit at a much slower speed, due to the collision of sucked-in water jets inside the device. The study's methods may have practical applications for devices responding to flowing air or water.