Echo-ranging is another name for which type of sonar?

Echo-ranging is another name for which type of sonar?

• A. Passive sonar
• B. Active sonar
• C. Radar-type sonar
• D. Light-based ranging

Answer: (B)

Echo-ranging is the process of emitting a sound pulse and listening for its echoes to determine distance to a target. This is precisely how active sonar works: you send out an acoustic signal and measure how long it takes for the echo to return, then use the known speed of sound in water to compute range. Passive sonar, on the other hand, only listens for sounds produced by others and does not emit anything, so it cannot determine range from echoes. Radar-type sonar and light-based ranging aren’t describing this acoustic echo method, since radar uses electromagnetic waves and light-based ranging uses light, not sound. So the technique described by echo-ranging aligns with active sonar.

Echo-ranging is the process of emitting a sound pulse and listening for its echoes to determine distance to a target. This is precisely how active sonar works: you send out an acoustic signal and measure how long it takes for the echo to return, then use the known speed of sound in water to compute range. Passive sonar, on the other hand, only listens for sounds produced by others and does not emit anything, so it cannot determine range from echoes. Radar-type sonar and light-based ranging aren’t describing this acoustic echo method, since radar uses electromagnetic waves and light-based ranging uses light, not sound. So the technique described by echo-ranging aligns with active sonar.