In SONAR, we use ultrasonic waves (option a). explains that SONAR systems use ultrasonic waves to detect objects and measure distances, Unacademy and Vedantu. These waves have frequencies above the range of human hearing, making them suitable for underwater applications.
Here’s why the other options are incorrect:
Infrasonic waves
have frequencies below the range of human hearing, making them less suitable for SONAR.
Radio waves
are electromagnetic waves, not sound waves, and are not typically used in SONAR.
Audible sound waves
are within the range of human hearing and are not as effective for penetrating water over long distances compared to ultrasonic waves.
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