Modelová Otázka ID 3293 - 
Které z následujících tvrzení o ultrazvuku je správné?
Správná odpověď je: A, B, C
Rychlost šíření akustického vlnění není závislá na frekvenci, pro dané látkové prostředí, jímž se vlna šíří, je však konstantní. Ultrazvuk je využíván např. netopýry k echolokaci, tedy k orientaci v prostoru na základě vysílání a příjmu ultrazvukových vln. Ultrazvuk spadá podobně jako zvuk (slyšitelný zvuk) a infrazvuk mezi mechanická vlnění. Při ponoření ucha do vody je sice možné slyšet zvuky šířící se vodou, které nad hladinou slyšet nelze, ultrazvukové vlnění však lidské ucho nedokáže poslouchat ani pod vodní hladinou.
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