Setting the Stage
An opera singer hits a high note, rattling the audience’s ear drums and exploding a wine glass in the drawing room. You may have seen this in the movies, but is this really possible with sound alone? Is an acoustic assault from the human voice powerful enough to shatter glass?
If you asked someone off the street to try this experiment, they’d likely attempt to do two things: sing as loud as they possibly can and sing in the highest possible pitch. The result? All the dogs in the neighborhood might start barking, but the glass would very likely remain intact. A person could scream himself or herself blue in the face, but at the wrong pitch most of the forces from his or her voice would be reflected, leaving the glass unharmed.