(1)由图知振幅A=0.02m,波长λ=8m. (2)若波向右传播:波传播的距离为△x=(n+)λ (m) (n=0,1,2,3,…) 则波速为v===40(4n+1)m/s (n=0,1,2,3,…) 若波向右传播:波传播的距离为△x=(n+)λ (m) (n=0,1,2,3,…) 则波速为v===40(4n+3)m/s (n=0,1,2,3,…) (3)波传播的距离为△x=v△t=280×0.05m=14m=1λ 所以波向x负方向传播. 答: (1)该波的振幅为振幅A=0.02m,波长λ=8m. (2)若这列波向右传播,波速是40(4n+1)m/s,(n=0,1,2,3,…);若这列波向左传播,波速是40(4n+3)m/s,(n=0,1,2,3,…). (3)当波速为280m/s时,波的传播方向向x负方向. |