The Physics of . . . Waterslides

Standing 76 feet above Orlando, Florida, staring down the throat of the Blue Niagara slide at the Wet’nWild water park, some riders have been known to have second thoughts. Powerful pumps churn the cascading water at the top of the slide into a furious froth, muffling the sound of parkgoers seven stories below. “Just go for it!” the ride operator urges, and another human torpedo surrenders to the froth, accelerating to a velocity of about 40 feet per second while careering through the slide’s 300 feet of looping tubes.