The porpoise would hear its echo first when both are 16 meters from an object because sound travels faster in water than in air. This conclusion is based on the principle of echolocation used by bats and dolphins to navigate and hunt.
If a porpoise and a bat both produce ultrasonic waves when they are 16 meters from an object, we need to determine which animal would hear its echo first. The speed of sound is different in various media; it travels faster in water than in air. Therefore, the porpoise would hear its echo first because sound travels faster in water than in air. This has little to do with the frequency of the sound waves, as the frequency does not affect the speed of sound within a given medium.
Echolocation is a technique used by various animals, like bats and dolphins, to sense their environment by emitting sound waves and listening for echoes. This ability to determine distance through sound is crucial for navigation and hunting, especially in the dark or murky environments where visual cues are limited.