Question

Give 1 application where principle of echo is utilised

Answer 1

It is used in SONAR (SOund Navigation And Ranging), it sends out a sound wave which reflects back and is received by the ship which it was sent by. The time taken for the reflected sound wave to be received is calculated to know how deep the object is or how far it is. Received after a longer time means it is further away and if it is received in a short time, then it is near.

Answer 2

echo is used in hydro graphic studies.