Question

Which of the following is used in SONAR

• A. Ultrasonic sound
• B. Infrasonic sound
• C. Supersonic sound
• D. Infra-red radiation.

Answer 1

The correct option is A

Ultrasonic sound

Explanation of correct option:

Option A:

1. The full form of SONAR is Sound Navigation and Ranging.
2. Ultrasonic sounds have a frequency of greater than 20,000 Hz.
3. Ultrasonic sound can penetrate the water for long distances because of its high frequency and shorter wavelength.
4. This is why we use Ultrasonic sound in SONAR because of their high penetrating power.

Explanation of incorrect option(s):

1. Option B: Infrasonic sounds have less frequency compared to ultrasonic sounds, so they are not able to penetrate water for a longer range.
2. Option C: Supersonic sound is used in Military fighter aircraft. Its speed is greater than the speed of sound.
3. Option D: Infrared-Radiation is also known as Heat or thermal or electromagnetic waves.
   They are used for heating purposes like therapeutic purposes where patients require physical therapy.

Hence, the Correct option is A: Ultrasonic sound