Study confirms theory explaining Feynman's reverse sprinkler puzzle

A new study has validated a 2024 momentum flux theory that explains the mechanics behind Feynman's long-debated reverse sprinkler problem. The theory proposes that the angular momentum of water flows is the key driver of sprinkler rotation. Researchers found that the same theoretical framework also applies to so-called 'silly sprinklers,' extending its explanatory reach. The findings help resolve a physics puzzle that Nobel laureate Richard Feynman once famously posed about how sprinklers behave when water is sucked in rather than expelled.