When an object moves through a fluid, it displaces that fluid in the form of a shock wave. The path left by a speedboat in water is an example of a shock wave. A sonic boom is a special kind of shock wave produced when an object travels though air at a speed greater than the speed of sound (1,100 ft/sec [335 m/sec] at sea level). Supersonic aircraft, such as the Concorde, produce a sonic boom when they fly faster than the speed of sound. A number of adverse environmental effects have been attributed to sonic booms from supersonic airplanes. These include the breaking of windows and the frightening of animals and people.