Properties of Waves: Wavelength (λ):             The distance between two successive crests or troughs of a wave is called wavelength. It is denoted by the Greek letter lambda (λ). Its S.I. unit is a metre (m). but for convenience, it is often measured in nanometers and angstrom.                  1 nm = 10-9 m             1 AoProperties of Waves | Wave Length ,Frequency , Wave Number