• 2022-07-01
    已知一均匀平面波以b=30 rad/m在空气中沿x方向传播,则该平面波的频率为( )
    A: [img=129x43]1802fb41b3749f5.png[/img]
    B: [img=129x43]1802fb41c0493d6.png[/img]
    C: [img=129x43]1802fb41c96b56b.png[/img]
    D: [img=129x43]1802fb41d2b07a1.png[/img]