Question

What is an echo? What are the necessary conditions for its occurrence? What is SONAR? How is it used to determine the depth of an ocean?

Answer 1

Hint: The reflection of sound waves that arrives at the listener after the direct sound with a delay is called Echo. A technique that uses sound propagation to detect, communicate objects under the surface of the water. That technique is called SONAR. Using these statements, we can determine the necessary conditions for the echo occurrence and how to determine the depth of an ocean.

Complete step by step answer:
The distance of the reflecting surface from the source to the listener is proportional to the delay. Acoustic waves are reflected by walls or any hard surfaces. Discontinuity in the propagation medium is due to the reflection. When the echo is reflected multiple times from multiple surfaces, then the echo is called reverberation.

The necessary conditions for its occurrence are the distance between the source(sound) and the reflecting sound surface must not be less than $17meters$. The time period between the original sound and its echo should be more than $0.1\sec $. If the time period between the two successive sounds is less than $0.1\sec $, then the human ear cannot distinguish it. In order to hear an echo, there should be a high raised building.

A technique that uses sound propagation to detect, communicate objects under the surface of the water. That technique is called SONAR. Acoustic location and measurement of the echo characteristics can be found by SONAR.

The depth of the ocean can be measured using the device SONAR. SONAR sends out sound waves and measures how long it takes the echo to return. If the water is shallow, then the sound waves reflect off the bottom of the ocean will return faster than in the deep sea. The sound waves take longer to travel to the bottom and back in deeper water. Ships and submarines use SONAR to navigate at sea.

Note: The way the seafloor is mapped is changed after the invention of SONAR. Different frequencies of sound to find out different things about the ocean uses echo frequency. The distance of the reflecting surface from the source to the listener is proportional to the delay. Ships and submarines use SONAR to navigate at sea. Acoustic waves are reflected by walls or any hard surfaces.