Final answer:
Smaller cavities resonate at higher frequencies, while larger cavities have lower resonant frequencies due to their ability to accommodate longer wavelengths.
Step-by-step explanation:
Smaller cavities vibrate at a higher resonant frequency because resonant frequencies for a given cavity are determined by its size: small cavities have shorter wavelengths corresponding to higher frequencies. Conversely, larger cavities vibrate at a lower resonant frequency, as they can accommodate longer wavelengths, which correspond to lower frequencies. This principle can be observed in musical instruments, such as flutes, which have different resonant cavities leading to their various pitch sounds. Additionally, the human voice is affected by the size of the resonant cavities formed by the throat and mouth, with the change in larynx size during puberty causing a significant difference in voice pitch between sexes.