問題詳情
7.如右圖所示，平面地圈中的X軸上，對稱Y軸各有一電磁波波源P及Q，發出相同频率 、相同振幅的正弦電磁波。今在Y軸的兩側選定兩點A、B，欲使A點收訊為最強時 ，B點恰好收訊為零；反之亦然。則兩波源可以 
(A)為同相位
(B)恰為反相
(C)相位差(1/4)
(D)相位差(1/8)
(E)理論上無法達成目的。
(A)為同相位
(B)恰為反相
(C)相位差(1/4)
(D)相位差(1/8)
(E)理論上無法達成目的。
參考答案
答案：C
難度：非常困難0
統計：A(0),B(2),C(0),D(0),E(3)
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