Sound is observed to travel at different speeds in different media.
(a) Arrange the following media in order of increasing speed of sound and justify your answer briefly: air at 25∘C, distilled water at the same temperature, and iron.
(b) Explain on the basis of particle arrangement and elastic properties why sound travels fastest in solids and slowest in gases.
(c) Draw a neat diagram of a longitudinal wave travelling along a slinky. Mark on your diagram one wavelength λ and the amplitude A of particle vibration.
(d) Distinguish clearly between wavelength and amplitude of a sound wave.