Question

A body vibrating with certain frequencies and wave 15 cm long to A medium a and 20 cm long through a medium be the velocity of waves in a 1200 M per second find the velocity in b

Answer 1

Suppose frequency of the vibrating body = n

In medium A. wavelength, λ1= 15 cm=0.15m

                        velocity, v1 = 1200 m s−1

                                                       n = v1 / λ1

                                             = 1200 / 0.15

                                             = 8000 Hz

In medium B.    Frequency, n =  8000Hz

                   wavelength, λ2 = 20 cm=0.2m

therefore,           velocity, v2 = n X λ2

                                          = 8000 X 0.2  

                                          = 1600 m s−1

hence velocity of the waves in medium B = 1600 m/s.