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Yes.
Active sonar generates a pulse, the echo is heard some time later. The time it takes for sound to travel from the generator to the reflector and back to the sensor discloses the distance from the sonar equipment to the object reflecting the sound waves.
Passive sonar just listens and does not generate any sound pulses itself but through various analysis algorithms certain information about the distance to an object that does make sound can be obtained. Passive sonar is not used for finding the depth of water but for listening to ships.
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How does the Navy use SONAR?
SONAR (Sound Navigation and Ranging) is a long-used method of locating submerged submarines by means of underwater echo-location. It was developed and used effectively during WWII; however, though used today, modern submarines are much more able to defeat surface sonar systems to the point where they're much less effective in Anti-Submarine Warfare (ASW) operations than they were in WWII. Speed, increased diving depth, stealth hull coatings, and tactical knowledge and use of the surrounding ocean environment all give the submarine the advantage over surface ship and aircraft sonar systems.Sound travels much faster in water than it does air, and travels much farther as well. Active/Passive systems use a transducer array, which is a large array of devices (transducers) that convert electrical signals to sound (for active transmitting) and sound waves to electrical signals (for passive reception of sound or receiving a return echo). Passive-only arrays (towed arrays and secondary forward arrays) use hydrophones rather than transducers, which can only receive sound waves and convert them to electrical signals.It should be noted that contrary to wild and baseless accusations by environmental and whale groups, the U.S. Navy (or any other Navy for that matter) does not go around the ocean using active sonar on a regular basis. Active sonar, even on surface ships, is rarely used, as it is an immediate location giveaway for an enemy. Giving up your tactical position is the one thing you never want to do when fighting against a submarine.SURFACE SHIP SONARSurface Warships use 3 primary Sonar systems:Hull mounted (bow) Sonar, Active and PassiveVariable Depth Sonar (VDS), towed behind the ship, PassiveEmbarked Aircraft (Helo) using dipping Sonar or Sonobuoys, Active and Passive.Bow sonar systems on surface ships isn't that effective at any speed over 10 knots, as the resulting ocean noise effectively drowns out any noise a submarine makes. Modern submarines are extremely quiet, and it takes the right conditions to even detect them.VDS systems allow the Sonar Techs to adjust the array depth to search ocean layers for submarines. VDS is actually pretty effective, if the Sonar crew is up to snuff and knows how to use it. However, the problem still exists that the submarine has the tactical advantage of using the environment, or if necessary, egressing out of the area at high speed and deep depth if detected.HELO DIPPING SONARDipping Sonars are small sonar arrays that have active/passive sonar capability. They are lowered from an equipped ASW helo by cable into the water, where an onboard tech will listen and view any sounds / frequencies that are being picked up. Their downside is that the rotor wash from the helo causes enough sound that it tends to interfere with the array, but it can be lowered deep enough to mitigate the effect.Many ASW ships have embarked ASW helos with dipping sonars, and those helos can also be equipped with homing torpedoes which can be launched if a target is located.SONOBUOYSSonobuoys are expendable passive sonar arrays that are dropped from aircraft (e.g., P-3 Orion ASW aircraft) in a known pattern, and then listened to by onboard techs on the aircraft for any sounds for frequencies coming from a submarine. They are very effective if a submarine is shallow enough to be heard, and if the ocean conditions are good enough for proper sound propagation. If a boat is deep enough however, they're just ocean ornaments.They're battery operated, and can last several hours.SUBMARINE SONARContrary to popular belief, submarines don't use their main sonar systems for primary navigation (they don't have windows either), and the Sonar acronym meaning (Sound Navigation and Ranging) is actually a misnomer. However, they do use it for avoiding objects (ships and submarines), so in that sense they do use it for avoidance navigation.Submarines use 2 types of Sonar modes - Active and Passive. Active Sonar is equivalent to Radar, only it uses sound waves rather than radio waves as the source of the transmission and echo for target range. Passive Sonar, which is used almost 99% of the time, involves simply listening with all systems for signs of ships, aircraft, or submarines (yes, we can hear planes and helos if they're close enough to the water).All submarines use chart, satellite, gyro, visual, radar (close to shore), and dead reckoning for primary navigation in most oceans. On rare occasions, uncharted mountains or navigational screwups have led to submarine accidents. My own boat hit an underwater mountain in the Mediterranean in 1977; the USS San Francisco hit an uncharted mountain a few years ago.The one exception is in the Arctic Ocean, where the ice pack is in constant motion and its configuration is ever-changing. In the Arctic, for fast travel, the boat will submerge to a deeper depth than ice keels can form; for navigating through the ice pack near the surface, forward-looking and top-sounding hi-frequency sonar is used to both detect ice and determine its relative thickness. The periscope can also be raised (the water is extremely clear there) to get a visual confirmation of ice configuration prior to surfacing.Navigating in the Arctic isn't easy. The aggravating, constant noise from the ice shifting (think about having to listen to popcorn pop for hours while trying to find a target) makes it very difficult to pick out contacts. Fortunately, there aren't any noisy biologics (fish, etc.) or shipping noise to make it worse.The primary use is for a submarine's main Sonar system is to find surface and submerged contacts. Depending on the type of boat (Attack or Missile) or ship and its mission, a boat will either seek out those contacts or seek to avoid them altogether. It is the mission of a Fast-Attack submarine to seek and destroy ships and submarines; a Ballistic Missile submarine's mission is to remain undetected. For those like me who were Sonarmen during the height of the Cold War, being on a Fast-Attack was the only way to go if you wanted to learn your profession.Not that submarines can't use their main sonar systems to navigate if they wanted to - they could. It can be used for navigation in shallow, close-to-shore waters, but in the deep ocean you can't due to the physical configuration of the Sonar array (more on that below). To use sonar for navigation, a boat needs to use Active Sonar. All boats use Passive Sonar exclusively for normal operations - active is only used to get a range confirmation on a target just prior to torpedo launch, or in other rare circumstances. The reason for this is that a boat's active sonar is extremely powerful, and as such can be heard by other ships and submarines for many, many miles (sound travels faster and farther in water than it does in air). So using active sonar effectively gives away your position. In submarine warfare, he who hears the other one first wins.Active Sonar depends on a clear echo return from an active pulse for navigation. As such, the echo is dependent on the return angle of the sound back to its source. The problem in deep ocean is that bottom is far enough away from the Sonar array that the angle at which the sound hits means that the echo will travel away from the source, not back toward it. This is why fathometer transducers are located on the bottom of the hull and slightly angled toward the bow to compensate for traveling through the water.Even using Active Sonar for navigation close to shore isn't that easy, nor is it really that accurate. The power output is so great that the resulting echoes make for a pretty messy return image. Sure, you can adjust the power levels, but the reality of today's submarine operations is that the only time you could really use it is when transiting to and from port, and in those cases you'd be using satellite, chart, and visual aids, which are more accurate. Fathometer soundings are used regularly to correlate with chart information, and satellite fixes are checked with other systems.In the case of using Passive Sonar, how sound travels in water is affected by temperature, salinity, and atmospheric pressure. Sound travels toward colder water, so as such tends to travel toward deep water. However, at deeper depth, pressure becomes the overriding variable and sound is forced back toward the surface. It is Sonar's job to chart the sound profile of the operating area on a regular basis so that the Sonar system can be used to full efficiency. Listening to Passive Sonar is essentially trying to pick out distinct sounds among the thousands of sounds created by biologics and environmental sources (storms, geologic sources, waves, etc.) as well as the thousands of ships and other man-made sources on the ocean or on the shore, trying to determine if the Sonar contact fits into the class of a Merchant ship, Trawler, Warship, or other type (Sailboat, Cruise ship, etc.).
How would you measure a road?
Depends on whether you want to measure the length (drive along it), its width (surveying equipment or large tape measure), depth of tarmac or concrete (drill samples), evenness, water dispersal or any of the host of other measures.
Who invented sonar?
It was Lewis Nixon who invented the very first sonar-type listening device in 1906. He was seeking a way of detecting icebergs. But the sonar was not "invented", its inventor was nobody, but developed through the years.Sonar had very humble beginnings, from crude instruments to advanced technology. (However, the natural sensory process cannot be invented, see bisonar or echolocation for that.) The first attempts to interpret sound waves created by vessels was by Leonardo Da Vinci in 1490, when he used a tube that detected vessel movements when placed in water.
What was the depth of the water the Lusitania sank in?
Over 200 metres deep
How much water does it take to fill a 16 x 32 pool?
Without knowing the average depth of your pool, it is impossible to know. However, assuming the average depth of your pool is 4 feet, it hold 15360 gallons of water.
Which instrument used to measure the sound under the water?
Sonar detector.
Which of these uses sound waves to measure the distance between objects underwater?
Sound waves bounce off the ocean floor and come back up to whatever emitted it. The time it takes for the sound wave to come back tells how far down it went. Doing this many times over and over, one can map out the ocean floor, and if the sound wave comes back relatively fast, that means there is something on the ocean floor.
What sends sound waves through water?
the sonar
What do Scientsts use sonar for?
Scientsts use sonar to map the depth of water in sea and river etc..,they also use sonar to locate and identify object underwater
Can a sonar machine identify the object showing up on the sonar?
Sonar (which stands for SOund NAvigation and Ranging) can be made to identify the object it pings on - if active sonar; if passive sonar, identify the object making the sound it picks up. The higher the frequency of the active sonar ping, the better the resolution - but the shorter the range. At higher resolutions, it is not hard for the sonar to identify the object it pings on. At lower frequencies, the range is greater but it is harder for the sonar to identify what is being pinged. Another benefit of active sonar is the range and direction of the target can be discerned. Passive sonar just listens to the ambient water. Identification of the sound source can be made if the frequencies of the target making the sound are known and identified in a database. One problem with passive sonar is that it is hard to know the range of the target making the sound, although the direction will be known. Water temperature and depth have a great effect on sonar, so this must be taken into account when calculating distance. Sonar is used in the Military, Geological Surveying, and the Medical field.
Can sonar be used out of water?
sonar can not be used outside water it is used under water to transmit sound waves through ultrasonic pulses
What is a device that bounces sound waves off underwater objects?
Any sound waves that happen to be propagating through the water will bounceoff of any objects that are there. No device is required to make that happen.A system that intentionally generates sound waves underwater, and then receivesand analyzes those that return after bouncing off of something in the water, is aSONAR system.
What is the correct definition of sonar?
1. A system using transmitted and reflected underwater sound waves to detect and locate submerged objects or measure the distance to the floor of a body of water.2. An apparatus, as one in a submarine, using sonar.3. Echolocation.http://www.thefreedictionary.com/sonar
What do sonar systems find?
Objects by sound. Mostly in water
What can A sonar device that uses the echoes of the ultrasound underwater find?
it measures the depth under water
Sonar measures underwater distances by using what?
Using the speed of sound in water (about 1500m/s in the sea, depending on the specific sea-water density). So if there is a delay of 2 seconds between a depth-sounding sonar emitting a pulse and detecting its echo from the sea-bed, the water is 1500 X 2 = 3000m deep.
How does an echo sounder works What are advantages and disadvantages of an echo sounder?
An echo sounder works by sending sound waves into the water and measuring the time it takes for the sound to bounce back to calculate the depth of the water. The advantages of an echo sounder include its ability to measure water depth accurately and quickly, useful for navigation and mapping purposes. However, disadvantages can include limitations in shallow water areas and interference from noise or other echoes.
