To determine the best definition of the term "period" in the context of waves, we need to understand the fundamental properties associated with wave motion. Let's break down each option provided:
A. The number of waves that pass a point in one second
- This definition describes the "frequency" of a wave, not its period. Frequency measures how often waves pass a specific point over a set time frame (usually one second).
B. The distance between waves
- This refers to the "wavelength" of a wave. Wavelength is the spatial period of a wave—the distance over which the wave's shape repeats.
C. The speed at which a wave travels
- This is the "speed" or "velocity" of the wave. Wave speed is how fast a wave propagates through a medium.
D. The time it takes for one full wave to pass a point
- This is the correct definition of "period." The period is the duration of time it takes for one complete cycle of the wave to pass a given point.
Given these explanations, the best definition of period is:
D. The time it takes for one full wave to pass a point
This answer properly describes the period, which is measured in units of time (such as seconds).