Place this clip at the moment of the fall itself, after a setup shot and before the reaction. Follow it with a fail sound meme for a bigger mishap, or keep it alone as the only effect before cutting to the aftermath.
关于此声音
This is a very short cartoon effect built from a whistling whirl, a jew's harp boing and a snapping boink. It feels silly and slapstick, turning a simple fall into a playful punchline. The clip comes from the Goofy cartoon Goofy Gymnastics, released in 1949.