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... The Auditory System This module explains how we hear and how the physical nature of the sound wave determines the quality of the sound experience. 1. What must the ear detect in order for hearing to take place? ...
... The Auditory System This module explains how we hear and how the physical nature of the sound wave determines the quality of the sound experience. 1. What must the ear detect in order for hearing to take place? ...
Sound barrier
The sound barrier or sonic barrier is a popular term for the sudden increase in aerodynamic drag and other effects experienced by an aircraft or other object when it approaches supersonic speed. When aircraft first began to be able to reach close to supersonic speed, these effects were seen as constituting a barrier making supersonic speed very difficult or impossible.In dry air at 20 °C (68 °F), the sound barrier is reached when an object moves at a speed of 343 metres per second (about 767 mph, 1234 km/h or 1,125 ft/s). The term came into use in this sense during World War II, when a number of aircraft started to encounter the effects of compressibility, a number of unrelated aerodynamic effects that ""struck"" their aircraft, seemingly impeding further acceleration. By the 1950s, new aircraft designs routinely ""broke"" the sound barrier.