Analysis  actually the wavelength which is affected Is this also the case for moving observer stationary source    Regd Analysis section Does not explicitly mention which case is analysed  I assumed moving source stationary observer  It explains So it is actually the wavelength which is affected Ok  However in the other case moving observer stationary source I was confused by the phrase similar analysis Analysis may be similar but does the same explanation actually the wavelength which is affected hold In this case doesnt wavelength actually remain same and relativeperceived sound speed change thus affecting perceived frequency