Which of the following is NOT commonly associated with the term frequency?

The concept of frequency is fundamentally linked to waves, vibrations, and oscillations, which all describe phenomena that repeat over time.

Waves are characterized by their frequency, which is the number of cycles that occur in a given time period, typically measured in Hertz (Hz). Similarly, vibrations involve the oscillatory motion of particles, where frequency denotes how frequently these particles oscillate per unit of time. Oscillations describe the regular variation of a quantity around a central value, and frequency is a key aspect of identifying how often these oscillations occur.

In contrast, particles are not inherently defined by the concept of frequency in the same way the other terms are. While particles can exhibit wave-like behavior (as described by quantum mechanics), the term frequency is not directly applied to them without the context of a specific oscillation or wave phenomenon. Thus, this distinguishes particles from the other terms associated with frequency.