2+uses+of+Doppler+-+Allison+S.

=
 The Doppler effect is used in the military. They use it to measure the speed of submarines through sonars or "the Doppler effect". Frequencies from the sonobuoy will undergo the Doppler Effect when they strike a moving object or submarine. It is then recorded and the observer can record the velocity that the object is approaching or leaving. =====

=
A jet flying overhead produces a loud sound, called a sonic boom. As the jet gets closer to you, the sound becomes more intense, causing some people to coer their ears. The sonic boom is not an effect of the Doppler effect completely, but an example of sound compression. The speed of sound is dependent on the medium through which it travels, so there is only a speed at which sound waves are transmitted through a given type of material.  As a jet moves through the air, it too produces sound waves which compress toward the front, and widen toward the rear. Since sound waves themselves are really just fluctuations in pressure, this means that the faster a jet goes, the greater the pressure of the sound waves bunched up in front of it. =====