What do you mean by an echo? What should be the minimum distance of the reflector to hear the echo of a transient sound? Mention some practical applications of echo.
An echo is a reflection of a sound wave that is perceived as a distinct repetition of the original sound.
The minimum distance of the reflector to hear the echo of a transient sound is approximately 17 meters in air.
Some practical applications of echo include:
- Echolocation: Bats and whales use echolocation to navigate and find prey in darkness or murky water. They emit ultrasonic pulses and listen to the echoes to create a mental map of their surroundings.
- Sonar: Sonar is a system that uses sound waves to detect and locate objects underwater. It is used by ships and submarines to navigate and avoid obstacles.