Dolphins communicate through the emission and reception of sounds. A young dolphin was separated from its mother and started whistling at a frequency of 130 kHz to call her. The speed of sound in seawater is 1480m∙s-1.
7.1 Explain the term ultrasound. (2)
7.2 Calculate the wavelength of the young dolphin’s whistle. (4)
7.3 Another dolphin hears the distress call of the young dolphin 2 s later. How far apart are the two dolphins from each other? (4)
7.4 The speed of sound in air is 340 m∙s-1. Briefly explain why the speed of sound in air is different from the speed of sound in seawater. (2)
7.5 Describe how dolphins use echolocation to hunt their prey. (3)
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