what happens when you break the sound barrier

When an object breaks the sound barrier, it generates a compression wave or shock wave that is similar to a high explosive blast wave. As the object approaches the speed of sound, it approaches an invisible pressure barrier set up by the sound waves just ahead of the object. The compressed air in front of the object exerts a much larger than usual force on the object, causing a noticeable increase in the aerodynamic drag on the object. When the object has sufficient acceleration, it can burst through this barrier of sound waves and move ahead of the radiated sound. The change in pressure as the object outruns all the pressure and sound waves in front of it is heard on the ground as an explosion, or sonic boom. Anything exceeding the speed of sound creates a sonic boom, not just airplanes. An airplane, a bullet, or the tip of a bullwhip can create this effect; they all produce a crack. This pressure change created by the sonic boom can be quite damaging. At supersonic speeds, there is no sound heard as an object approaches an observer because the object is traveling faster than the sound it produces. Only after the object has passed will the observer be able to hear the sound waves emitted from the object. These time periods are often referred to as the zone of silence and the zone of action.