A Barreira do Som
Autor: MATEMÁTICA DA INFORMAÇÃO | Publicado: 2014-10-27T10:50:00-07:00

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&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; A
propagação do som no ar são ondas concêntricas, semelhante a uma pedra ao cair
em um lago. A barreira do som é o limite de velocidade em que um móvel pode
se deslocar sem tocar as ondas sonoras emitidas por ele mesmo. À medida que o
móvel acelera, essas ondas vão se juntando e ficando como que empilhadas à sua
frente. A velocidade do som no ar é de aproximadamente 1.200 km/h, e quando o
móvel supera esta velocidade (das ondas) esse cordão é rompido e ouve-se o
estrondo e a partir daí, as ondas ficam para trás e não há mais o estrondo.

Fonte: Superinteressante 08/2001