A person fishing from a pier obeserves that 4 wave crests pa

A person fishing from a pier obeserves that 4 wave crests pass by in 11s and estimates the distance between two successive crests to be 3.7m. The timing starts with the first wave crest and the ends with the last. What is the speed of the wave?

Solution

distance between two crest = 3.7m

so distance travelled by 4 crest = 3.7*3 = 11.1m

time taken to travel the distance = 11 seconds

hence speed = 11.1/11 = 1.009 m/s