3.
如图\((a)\),在\(xoy\)有两个沿\(z\)方向做简谐振动的点波源\(S_{1}(0,4)\)和\(S_{2}(0,–2).\)两波源的振动图线分别如图\((b)\)和图\((c)\)所示,两列波的波速均为\(1.00 m/s.\)两列波从波源传播到点\(A(8,–2)\)的路程差为________\(m\),两列波引起的点\(B(4,1)\)处质点的振动相互__________\((\)填“加强”或“减弱”\()\),点\(C(0,0.5)\)处质点的振动相互__________\((\)填“加强”或“减弱”\()\).
![](https://www.ebk.net.cn/tikuimages/8/2018/600/shoutiniao39/56f48c46edfd4504853cfca2749d5202.png)