Midterm question: Why is it that a subsonic aircraft, no matter how loud it may be, cannot produce a sonic boom?
Sound is a pressure wave.
As an object moves through the air, the pressure wave propagates ahead of it.
If the object starts traveling faster than the pressure wave, then the wave will build up in front of it, and produce a high pressure wake behind it.
To illustrate this, it’s similar to a boat traveling quickly through the water. If it travels faster than the waves it produces, then you get a huge wake, which will be familiar to anyone who enjoys sailing, but are plagued by the presence of power boats.
This wake is the same as the sonic boom. It doesn’t occur if you’re not traveling faster than the speed of sound.
November 28th, 2009 at 11:23 pm
Sound is a pressure wave.
As an object moves through the air, the pressure wave propagates ahead of it.
If the object starts traveling faster than the pressure wave, then the wave will build up in front of it, and produce a high pressure wake behind it.
To illustrate this, it’s similar to a boat traveling quickly through the water. If it travels faster than the waves it produces, then you get a huge wake, which will be familiar to anyone who enjoys sailing, but are plagued by the presence of power boats.
This wake is the same as the sonic boom. It doesn’t occur if you’re not traveling faster than the speed of sound.
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