Đại lượng được xác định bằng "Năng lượng sóng âm chuyển qua một đơn vị diện tích vuông góc với phương truyền sóng tại một điểm, trong một đơn vị thời gian" là
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- Cường độ âm (I) là đại lượng đo bằng năng lượng mà sóng âm tải qua một đơn vị diện tích $S$ đặt vuông góc với phương truyền sóng trong một đơn vị thời gian.
- Công thức: $I = \frac{P}{S}$, trong đó:
- $P$ là công suất của nguồn âm (W)
- $S$ là diện tích ($m^2$)
- $I$ là cường độ âm ($W/m^2$)
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Thông tin là gì?
Người ta thiết kế một cái tháp gồm \(11\) tầng. Diện tích bề mặt trên của mỗi tầng bằng nửa diện tích của mặt trên của tầng ngay bên dưới và diện tích mặt trên của tầng \(1\) bằng nửa diện tích của đế tháp.
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[I] Belgium features a fascinating mix of ancient traditions and contemporary legislation, showcasing the country’s rich history. [II]. In Belgium, the families of the bride and groom each pitch in by providing a sheet of paper for the wedding invitations, in line with a long-standing tradition. [III] The wedding invitations symbolize the new partnership and the merging of the two families. [IV]
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Dear Nhung,
a. I hope this email finds you well. I’m writing to let you know that I’ll be arriving in Hanoi next Monday and wanted to ask if you’ll be at home then.
b. Would it be possible for you to meet me at the airport?
c. Please let me know once you’ve received this email. I’m looking forward to hearing from you soon!
d. By the way, I was wondering if you could recommend some historical sites in northern Vietnam.
e. I am also planning to visit a few places there to gather materials for my Cultural Studies presentation.
Best regards,
Anna