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nguyendanglvt
2 năm trước
B3: Một hs gõ vào đầu 1 ống thép dài 2589m thì ở đầu kia hs 2 áp tai vào ống nghe thấy 2 tg gõ cách nhau 7,19s. Cho vận tốc trg ko khí là 340m/s a, Vì sao hs 2 nghe đc 2 tg gõ b, Thời gian lần lượt truyền âm qua ko khí, qua ống thép đến tai hs 2 là bn? c, Tính vận tốc truyên faam trg thép? HELP MEEEE
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