The document discusses how Bernoulli's principle applies to air flight, baseball, a standing tennis ball, and race cars. In air flight, the curved top of airplane wings and flat bottom cause faster moving air over the top, creating lift. In baseball, a spinning curveball's uneven air pressure causes it to drop due to the bottom accelerating faster. A tennis ball stands suspended due to equal air pressure balancing the downward force of gravity. Race car spoilers are curved to decrease top air velocity and increase pressure, keeping the car grounded during turns.