Question

which best describes pitch? the amount of time taken for a longitudinal wave to produce one cycle the number of cycles per second perceived by the human ear the amplitude of a wave when the natural frequency is matched the distance between two corresponding parts of a transverse wave

Explanation:

Pitch is related to the frequency of a sound wave. Frequency is defined as the number of cycles per second. When sound waves reach the human ear, the perception of this frequency is what we call pitch. Higher frequency (more cycles per second) is perceived as a higher - pitched sound, and lower frequency (fewer cycles per second) is perceived as a lower - pitched sound.

• The amount of time taken for a longitudinal wave to produce one cycle is the period ($T$), and $T=\frac{1}{f}$ (where $f$ is frequency).
• The amplitude of a wave when the natural frequency is matched is related to resonance (a phenomenon where the amplitude of a vibrating system increases when the frequency of an external force matches the natural frequency of the system), not pitch.
• The distance between two corresponding parts of a transverse wave is the wavelength ($\lambda$), and $\lambda=\frac{v}{f}$ (where $v$ is the wave speed).

Answer:

the number of cycles per second perceived by the human ear