An opera singer can break glass due to a phenomenon known as resonance, which occurs when the glass vibrates at its natural frequency.

Resonance is a key concept in physics, describing how an object vibrates at its inherent frequency when subjected to a similar frequency. In the scenario of an opera singer shattering glass, the singer’s voice generates sound waves that correspond to the natural frequency of the glass. When this match occurs, the glass begins to vibrate. If the vibration’s amplitude is sufficiently large, the glass can break.

The natural frequency of an object is influenced by various physical characteristics, including its size, shape, and the material from which it is made. For a typical piece of glass, this frequency usually falls within the range of human hearing, which is why an opera singer can potentially shatter it with their voice. However, it’s not merely about singing any note; the singer must produce a pitch that precisely matches the glass’s natural frequency and do so with enough volume to create a significant amplitude of vibration.

Additionally, the singer must maintain the note for a certain duration. This is crucial because the energy from the sound waves is gradually transferred to the glass. If the singer stops too soon, the glass may not have absorbed sufficient energy to break. This is why opera singers often hold a high note for an extended period when attempting to shatter glass.

In summary, an opera singer can break glass through the principle of resonance. By singing a note that aligns with the glass’s natural frequency and sustaining it long enough, the singer can cause the glass to vibrate with sufficient amplitude to shatter. This phenomenon beautifully illustrates the power of sound and the intricate balance of forces in the physical world.