Chapter 13 wave motion and sound 13-1 The Characteristic Quantities of wave: p327 波长九:沿波的传播方向,两个相邻的、相 位差为2π的振动质点之间的距离,即一个完整波 形的长度 The wavelength n of a wave is the distance between two successive crests xX AChapter 13 Wave Motion and Sound 13-1 The Characteristic Quantities of wave: p327  波长 ：沿波的传播方向，两个相邻的、相 位差为 的振动质点之间的距离，即一个完整波 形的长度. The wavelength  of a wave is the distance between two successive crests.  2π O y A - A  u x 