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khanhabng1502
2 năm trước
1 tàu ngầm phát ra siêu âm truyền trong nc và thu đc âm phản xạ sau 1 giây. biết vận tốc truyền âm trong nc là 1500m/s. xác định độ sâu đáy biển 1 cái cây mọc thẳng đứng ở bờ ao. cây cao 1,2m, gốc cây cách mặt nc 50cm. 1 người quan sát ảnh của cây thì ngọn cây cách ảnh của nó là bao nhiêu? mình vote 5 sao
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