SONAR stands for SOund Navigation And Ranging. It's a device that uses ultrasonic waves to measure distance, direction and speed of underwater objects. It is used to determine depth of sea and to locate underwater hills, valley, submarine, icebergs sunken ships etc. Hope it helps
SONAR stands for Sound Navigation And Ranging. It is used by the boats or submarines in water bodies so that they can find what is the depth of the water and if something has sunked into water i.e. boat, ships, etc., to find them SONAR is used. Also to find at what depth (range) the stone are or a creature is swimming.