在简谐波传播过程中,沿传播方向相距λ/2(λ为波长)的两点的振动速度必定(  )。

在简谐波传播过程中,沿传播方向相距λ/2(λ为波长)的两点的振动速度必定(  )。 A.大小相同,而方向相反 B.大小和方向均相同 C.大小不同,方向相同 D.

查看答案

一横波沿绳子传播时的波动方程为y=0.05Cos(4πχ-10πt)(SI),则(  )。

一横波沿绳子传播时的波动方程为y=0.05Cos(4πχ-10πt)(SI),则(  )。 A.波长为0.5m B.波长为0.05m C.波速为25m/s D.

查看答案

- __________ may I __________ the book?,-- For three weeks.

- __________ may I __________ the book?,-- For three weeks.A.How often; borrow

查看答案

Does Tom know any other foreign languages __________English?

Does Tom know any other foreign languages __________English?A.but B.except C.bes

查看答案

She thought I was talking about her son_________ actually, I

She thought I was talking about her son_________ actually, I was talking about m

查看答案