Wave frequency counts crests per second

Steps:

• Recall that waves have properties like height, length, speed, and repetition rate.
• Identify the repetition rate as how many full cycles (crests) pass a point in one second.
• Match this to the term that defines cycles per unit time.
• Confirm by excluding unrelated properties like size or distance.

Why B is correct:

• Frequency is defined as the number of wave cycles (crests) passing a point per second, often measured in hertz (Hz).

Why the others are wrong:

• A: Amplitude is the maximum height or displacement of the wave from equilibrium.
• C: Speed is the rate at which the wave travels through a medium, in distance per time.
• D: Wavelength is the distance between consecutive crests.

Final answer: B