Final answer:
Affricates lack sonority, which is why they cannot be the nucleus of a syllable. Their position in the phonetic segment hierarchy is lower than that of more sonorous sounds like vowels.
Step-by-step explanation:
Affricates cannot be the nucleus of a syllable because they lack sonority. Sonority refers to the relative loudness of a sound when compared with other sounds with the same length, stress, and pitch. In the hierarchy of phonetic segments, affricates are less sonorous than vowels or liquids, which makes them unfit to be the nucleus of a syllable. To address the other part of the context:
- The word or phrase used to describe the loudness of sound is 'intensity level' or 'decibel'.
- Turning up the volume of your stereo will not change the pitch because pitch does not depend on intensity. Instead, it is related to the frequency of the sound waves.