A vibrator generates 80 wavesin four seconds.the distance succesive between two succesive crests of the waves is 15cm. Determine the time taken for the waves to travel a distance of 180m
crest moves 0.15 meters in 4/80 seconds so speed = 80*0.15 /4 meters/second = 3 m/s
180 m / 3 m/s = 60 seconds or 1minute