Question

If a sound travels from air to water then which quantity will remain unchanged? a) velocity b) wavelength c) frequency d) amplitude

Answer 1

Just as with light the velocity is the product of frequency times wavelength. In the case of a sound of frequency f generated by a source S, the frequency does not change going from air to water. The speed of sound changes from 331 m/sec in air to 1480 m/sec in water. So the wavelength = v/f increases about 4.5 times in water compared to air. At 100 Hz frequency the wavelength in air is 11.3 ft. and in water its about 48 ft.