A dolphin emits ultrasound clicks at a frequency of 25kHz. The speed of sound in sea water is 1500m/s, while in air it is 340m/s.
(a) Calculate the wavelength of the clicks in sea water.
(b) The same clicks travel into air without any change in frequency. Calculate their wavelength in air.
(c) Explain why the frequency of the sound remains the same but the wavelength changes when the medium changes.