Longitudinal waves, also known as "l-waves", are waves in which the displacement of the medium is in the same direction as, or the opposite direction to, the direction of travel of the wave. The above is a schematic diagram of a sound wave at a particular instant, which is a longitudinal wave. [A] and [B] are the most compressed positions and the distance between [A] and [B] is \(50\) cm. Which of the following statements is correct?
The velocity of sound is \(340\) m/s.
a) The wavelength of this sound is \(1\) m.
b) The frequency of this sound is \(680\) Hz.
c) After one period passes, position [A] becomes a rarefaction.