FAA - SONIC BOOM NOISE AND OVERPRESSURE (Excerpt from U.S. Air Force atmospheric interceptor technology (AIT) Environmental Assessment ) NOISE METHODS OF ANALYSIS 1.0 NOISE DESCRIPTORS AND EFFECTS
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چکیده
Measurement and perception of sound involves two basic physical characteristics: amplitude and frequency. Amplitude is a measure of the strength of the sound and is directly measured in terms of the pressure of a sound wave. Because sound pressure varies in time, various types of pressure averages are usually used. Frequency, commonly perceived as pitch, is the number of times per second the sound causes air molecules to oscillate. Frequency is measured in units of cycles per second, or Hertz (Hz).
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