“beats”的概念、定义、翻译、参考文献-科学参考

beats

Physics

A periodic increase and decrease in loudness heard when two notes of slightly different frequency are sounded at the same time. If a note of frequency n is heard at the same time as a note of frequency m, the resulting note will have a frequency of about (n+m)/2. However the amplitude of this note will vary from the difference to the sum of the amplitudes of the m and n notes and the frequency (called the beat frequency) of this variation will be (m − n). The beating sound produced occurs as the waves successively reinforce and oppose each other as they move in and out of phase. Beating also occurs with radio-frequency waves and is made use of in heterodyne devices. See also interference.

Electronics and Electrical Engineering

The periodic signal produced by interference when two signals of slightly different frequencies are combined. The amplitude is equal to the sum of the original amplitudes; the frequency (the beat frequency) is equal to the difference between the original frequencies. The production of beats is termed beating and is achieved, for example, by using a beat-frequency oscillator. This device incorporates two radiofrequency oscillators, one producing a fixed frequency wave and the other a variable frequency; the output is produced by beating together the two frequencies.
Beating is also the basis on which a musical instrument is tuned by reducing the beats with a reference to 0 Hz by adjusting, for example, the string or pipe length.

单词	beats
释义	beats Physics A periodic increase and decrease in loudness heard when two notes of slightly different frequency are sounded at the same time. If a note of frequency n is heard at the same time as a note of frequency m, the resulting note will have a frequency of about (n+m)/2. However the amplitude of this note will vary from the difference to the sum of the amplitudes of the m and n notes and the frequency (called the beat frequency) of this variation will be (m − n). The beating sound produced occurs as the waves successively reinforce and oppose each other as they move in and out of phase. Beating also occurs with radio-frequency waves and is made use of in heterodyne devices. See also interference. Electronics and Electrical Engineering The periodic signal produced by interference when two signals of slightly different frequencies are combined. The amplitude is equal to the sum of the original amplitudes; the frequency (the beat frequency) is equal to the difference between the original frequencies. The production of beats is termed beating and is achieved, for example, by using a beat-frequency oscillator. This device incorporates two radiofrequency oscillators, one producing a fixed frequency wave and the other a variable frequency; the output is produced by beating together the two frequencies. Beating is also the basis on which a musical instrument is tuned by reducing the beats with a reference to 0 Hz by adjusting, for example, the string or pipe length.
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