SONAR works on the principle of:

SONAR, which stands for Sound Navigation and Ranging, is a technology used to detect and locate objects underwater using sound waves. The fundamental principle behind SONAR is the echo, which occurs when sound waves hit an object and are reflected back to the source.

In a typical SONAR system, a transmitter emits sound waves into the water. These waves travel until they encounter an object such as a submarine, ship, or the seabed. The sound waves are then reflected back to a receiver. By measuring the time interval between emission and reception of the sound waves, the system can calculate the distance and location of the object using the formula:

Distance=Speed of sound in water×Time2\text{Distance} = \frac{\text{Speed of sound in water} \times \text{Time}}{2}Distance=2Speed of sound in water×Time

The use of echo allows SONAR to operate effectively in underwater environments, where visibility is limited and other detection methods like radar are ineffective. SONAR can also provide information about the shape, size, and speed of underwater objects.

The other options are incorrect:

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  Reverberation refers to repeated reflections of sound in an enclosed space, not used for measuring distances underwater.

  
  


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  Resonance is the amplification of vibrations at a natural frequency and is unrelated to SONAR operation.

  
  

SONAR is widely used in naval operations, fishing, underwater mapping, and scientific research. It demonstrates how sound waves and the concept of echo can be applied to solve practical problems.

In summary, SONAR works on the principle of echo, using reflected sound waves to detect and locate objects underwater. This principle forms the basis for a wide range of applications in navigation, defense, and oceanography.