beats
In the case of two turbine aircraft engines that are rotating at nearly the same frequency but not precisely at the same frequency, four frequencies are generated. These are: (f1) the rotational frequency of turbine one, (f2) the rotational frequency of turbine two, (f1 + f2) the sum of turbine rotational frequencies one and two, and (f1 - f1) which is the difference or "beat" frequency of turbines one and two. The difference of the two frequencies is the lower frequency and is the one that is "felt" as a beat or "wow" in this case. Related categories WAVES AND WAVE PHENOMENA ACOUSTICS AND MUSIC Also on this site: Encyclopedia of Alternative Energy & Sustainable Living Encyclopedia of History |