Final Answer:
Yes, it is generally correct to assume that the strongest reflected pulse corresponds to the closest point to the sonar. This assumption holds true when dealing with a single beam echosounder with a cone-shaped beam, as the strongest reflection is more likely to come from the part of the cone closest to the object.
Step-by-step explanation:
In a single beam echosounder, the emitted acoustic pulse forms a cone underwater due to the beam angle. When this cone intersects with an object, the reflected pulses are received by the sonar. The strength of the reflected pulse is influenced by factors such as the target's size, shape, and composition. However, assuming a smooth, reflective surface, the majority of the reflected energy comes from the portion of the cone closest to the object. This is due to the inverse square law, which states that the intensity of a signal diminishes with the square of the distance from the source. As a result, the closest point to the sonar contributes the strongest reflection.
Furthermore, the time of flight for sound waves is directly related to distance. When the sonar emits an acoustic pulse, the time it takes for the pulse to travel to the object and back is used to calculate the distance. Since the strongest reflected pulse is more likely to originate from the closest point, using the time of flight data from this pulse helps in accurately determining the distance to the nearest part of the object within the cone. While other parts of the cone may contribute echoes, the strongest reflection generally corresponds to the closest intersection point, validating the assumption.