The distance of length of one complete cycle.

• A. Amplitude
• B. Period
• C. Frequency
• D. Wavelength

Answer: (D)

The distance covered by one complete cycle is the wavelength. In a wave, a cycle repeats in space as the pattern moves along, so the spatial distance from one identical point on the wave (like crest to crest or trough to trough) defines the wavelength. Amplitude describes how tall the wave is, not how far it travels in one cycle. The period is the time it takes for one cycle to pass a fixed point, not a distance. Frequency is how many cycles occur per unit time, also a rate rather than a length. If you relate speed, frequency, and wavelength, you get v = fλ, so the wavelength is the speed divided by the frequency.