OAR Test Practice Test

OAR Reading Comprehension: Main Idea Questions and Answers

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Read the following passage and answer the question. Active sonar systems operate by transmitting a sound pulse, often called a 'ping,' and then listening for the echo. This echo allows the system to determine the range and bearing of a submerged object. Passive sonar, in contrast, involves simply listening for sounds made by the target itself, such as engine noise or propeller cavitation. While passive sonar offers the advantage of stealth, as it does not emit any energy that could reveal the listener's position, active sonar generally provides more precise data on a target's location and movement. The choice between active and passive sonar often depends on the tactical situation, balancing the need for precise information against the risk of detection.
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