Scientists have finally solved the mystery of the physics behind the sound you hear when you clap your hands! The mechanism at work is a Helmholtz resonator—the same effect you get when you blow across the top of a bottle and produce a sound. It happens when air inside a hollow space—like a bottle or between your hands—vibrates at a certain frequency, creating a deep tone. The same principle is used in things like car mufflers to reduce noise and in some speakers to enhance bass sounds.
From Science News:
When a person claps their hands, a jet of air streams out of a gap where the hands meet, between the thumb and forefinger. "This jet of air carries energy, and that's … the initial start of the sound," says mechanical engineer Yicong Fu of Cornell University. The jet kicks off vibrations of the air. Fu and colleagues saw a similar effect using cup-shaped silicone models designed to mimic palms slapping together.
According to Fu, the research could lead to a method for logging into electronic devices by clapping. For instance, this could make it possible to log into a device using a person's unique clap pattern. Yep, it's the return of… THE CLAPPER!
Previously:
• Clapping at this Mayan temple echoes back as a quetzal bird call
• Acoustic solutions to ocean noise pollution
• Acoustic engineer explains why vuvuzelas are annoying
