Question

A distance between a crest and a trough is 20cm . in riples on the surface of water .when 20 riples are produced in one sec . calculate the time period and wave velocity

Answer 1

Wavelength is the distance between the two crest or trough.
Distance between crest and trough is 20 cm.
Hence wavelength is given by : $\lambda$ = 2×20 = 40 cm

frequency = 20 ripples per second
Time period = 1/frequency
= 1/20
= .05 seconds

wave velocity = wavelength × frequency
= 40 ×20 = 800 cm/s = 8 m/second