A student wants to know how many crests of a water wave are simultaneously present between two buoys that are 12 m apart. Which statement best explains why knowledge of the wave’s wavelength, rather than its period, is most useful for this task?
(a) Knowing the period lets you calculate the wave speed, and the speed determines how many crests span the 12m.
(b) Because wavelength is difficult to observe on moving water, the period is typically measured first to find the number of crests.
(c) Wavelength relates distance directly to the number of cycles, whereas period relates time to cycles.
(d) Since period is the reciprocal of frequency, it directly tells you how many crests exist within a given distance.