Một sóng ngang hình sin truyền trên một sợi dây dà...
Câu hỏi: Một sóng ngang hình sin truyền trên một sợi dây dài. Hình vẽ bên là hình dạng của một đoạn dây tại một thời điểm t0 xác định. Trong quá trình lan truyền sóng, hai phần tử M và N lệch pha nhau![](data:image/png;base64,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)
A. \(\frac{{2\pi }}{3}\)
B. \(\frac{{5\pi }}{6}\)
C. \(\frac{\pi }{3}\)
D. \(\frac{\pi }{6}\)
Câu hỏi trên thuộc đề trắc nghiệm
Đề thi thử THPTQG năm 2018 môn Vật lý THPT Chu Văn An- Hà Nội