Một ứng dụng của sóng dừng là đo tốc độ truyền âm trong không khí. Một nhóm học sinh dùng một ống thủy tinh hình trụ đặt thẳng đứng, phần dưới chứa nước có thể thay đổi độ cao (hình vẽ), phần trên là cột khí, sát miệng ống đặt một âm thoa dao động với tần số 517 Hz. Ban đầu khi cột khí trong ống cao 48 cm thì ở miệng ống nghe thấy âm to nhất. Hạ thấp dần mực nước tới khi chiều dài khí trong ống là 82cm lại nghe thấy âm to nhất. Hỏi nhóm học sinh đó tính được tốc độ truyền âm trong không khí bằng bao nhiêu?

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Một số câu hỏi khác có thể bạn quan tâm.

• Choose A, B, C or D to indicate the underlined part that needs correction in each of the following questions:

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• Choose A, B, C or D to indicate the underlined part that needs correction in each of the following questions:

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• Mark the letter A,B,C or D on your answer sheet to indicate the underlined part that needs correction in each of the following questions:

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• Mark the letter A, B, C or D on your sheet to indicate the underlined part that needs correction in each of the following questions:

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• Mark the letter A, B, C or D on your sheet to indicate the underlined part that needs correction in each of the following questions:

  I'd prefer to do it on myself  , because other people make me nervous.         

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• Mark the letter A, B, C, or D on your answer sheet to indicate the underlined part that needs correction in each of the following questions:

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• Mark the letter A, B, C, or D on your answer sheet to indicate the underlined part that needs correction in each of the following questions:

  The wooden fence surrounded the factory is beginning to fall down because of the rain.  

• Mark the letter A, B, C or D on your answer sheet to show the underlined part that needs correction in each of the following questions:

    Foreign students who are doing a decision about which school to attend may not  know exactly where the choices are located.

• Mark the letter A, B, C or D on your answer sheet to show the underlined part that needs correction in each of the following questions: 

  Fertilizer, which is added to the soil to replace or increase plant nutrients, include animal and green manure, fish and bone meal and compost.