As much as it seems like something dreamed up by cartoonists, opera singers actually can shatter wine glasses with their voices. In fact, you could probably do it, too.
Every wine glass, like other items, has a resonant frequency, which is the hertz level at which it’ll start to vibrate. Flick the glass, tap it lightly with a utensil, or rub a wet finger around the rim, and the sound it emits is at that resonant frequency. If you play that sound back to it loud and long enough, the molecules will vibrate so much that they’ll eventually lose their grip on each other, and your glass will go up in pieces.
The MythBusters, Physics Girl, and countless other curious people with a platform have investigated the phenomenon for themselves. The latest is The Slow Mo Guys, whose mission was to capture the whole endeavor in—you guessed it—slow motion.
Instead of enlisting an opera singer or using his own voice, host Gavin Free rigged up an amp to transmit the tone through a speaker right beside the glass. As Nerdist explains, he used a tone generator to find the glass’s resonant frequency, which was a little above 500 hertz.
In the video below, Free breaks a few different glasses so you can see how they shatter differently. The slow-motion footage is shot at 187,500 frames per second (for reference, the standard frame rate for a regular movie is 24 frames per second). It’s slow enough that you can see the shards of glass still vibrating on the way down.
If this video has awakened in you an appetite for more slow-motion content, you can watch The Slow Mo Guys detonate daytime fireworks here.