Question

the cork on the surface of water moves up and down completing 5 vibrations in 4 seconds . the wave travels from a cork to the shore which is 20m away in 10seconds . calculate speed, frequency, and wavelength

Answer 1

speed=20/10                                                                                                                          

         =2 m/s

frequency=1/4

wave length=2*1/4

                    =1/2

Answer 2

Time required to complete 5 vibrations=4seconds

So, time required to complete 1 vibration=4/5 second

Frequency=1/T=5/4=1.25Hz

Speed=distance/time=20/10=2m/s

wavelength=velocity/frequency=2/1.25=1.6m