Question

If you were standing at the end of a pier with a stopwatch in hand, how would you measure the average WAVE PERIOD of the waves that pass by?
Answer

Determine a fixed point on the pier and note the time between a crest and trough that reach that point.

Stand at the end of the pier and record the amount of time that it takes for a wave to break from the crest to its trough.

Stand at the end of the pier and record the distance from a wave's crest to its trough.

Determine a fixed point on the pier and note the time between a crest and the next crest that reaches that point.