Question

While practicing on the trumpet, you notice that every time you play a particular note, a window in the room rattles. How can you explain this rattling in terms of wave behaviors?

Answer 1

This is due to mechanical resonance. The window has a frequency of vibration that is the same as the note being played. The vibrations from the sound travelling in the air are transferred to the window. Because they vibrate at the same frequency, vibrations will build up in the window. This is much like what happens when a singer sings a note and shattters a wine glass.