This document discusses ultrasound and SONAR. It begins by defining ultrasound as high frequency sound waves that are above the range of human hearing. It then lists several medical and industrial applications of ultrasound, such as using it to detect fetal abnormalities, clean teeth, and break up kidney stones. The document defines SONAR as a technique using sound propagation to navigate, communicate, or detect objects underwater. It is commonly used by militaries to detect submarines and by fishermen to locate schools of fish. The document concludes with several multiple choice questions to test the reader's understanding.
2. INDEX:
What is Ultrasound?
Some applications of ultrasound.
What is SONAR?
Some applications of SONAR.
Quiz to test your knowledge..
3. What is Ultrasound?
• Ultrasound is cyclic sound pressure with a frequency greater than the
upper limit of human hearing, or high frequency waves. Ultrasound is
thus not separated from "normal" (audible) sound based on differences in
physical properties, only the fact that humans cannot hear it. Although
this limit varies from person to person, it is approximately 20 kilohertz
(20,000 hertz) in healthy, young adults. The production of ultrasound is
used in many different fields, typically to penetrate a medium and
measure the reflection signature or supply focused energy. The reflection
signature can reveal details about the inner structure of the medium, a
property also used by animals such as bats for hunting.
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4. Some applications of Ultrasound.
• In industry, ultrasound is used to determine how thick objects such as
metals and plastic are.
• Ultrasound has been shown to work with antibiotics in killing bacterial
cells.
• Bacteria, particularly those in sewage, can be disintegrated (killed) by
using ultrasonic waves.
• Believe it or not, ultrasound can be used to clean teeth. Dental
hygienists use ultrasound.
• Focused pulses of ultrasound can break up kidney stones and gallstones
into little fragments that can be passed from the body with less
difficulty.
5. • Recently, studies have shown that ultrasound can stimulate the
growth of bones.
• Ultrasound is used in elastography. This allows doctors to work
out which tissues in the body are healthy and which are
unhealthy.
• Ultrasonic waves are made to reflect from the heart to form the image
of the heart. This is known as ‘echocardiography’.
• Ultrasonic waves can be used to weld plastic together. The waves
make heat energy between the objects that are joined.
• Ultrasonic cleaners are used by jewelers and doctors to clean
things like watches, jewelery, lenses and surgical instruments.
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Detection of developmental/ structural abnormalities in the fetus.
Diagnosis of gallbladder disease/ obstruction.
Evaluation of blood flow in blood vessels.
Assessment of the thyroid gland in your neck.
Evaluation of the heart and diagnosis of cardiac problems.
Revealing the presence of infection in a specific area of the body.
Determination of abnormal structures/ growth in a particular area.
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7. What is SONAR?
• Sonar (originally an acronym for SOund Navigation And Ranging) is a
technique that uses sound propagation (usually underwater, as in
submarine navigation) to navigate, communicate with or detect other
vessels. Two types of technology share the name "sonar": passive sonar is
essentially listening for the sound made by vessels; active sonar is
emitting pulses of sounds and listening for echoes. Sonar may be used as
a means of acoustic location and of measurement of the echo
characteristics of "targets" in the water. Acoustic location in air was
used before the introduction of radar. Sonar may also be used in air for
robot navigation, and SODAR (an upward looking in-air sonar) is used
for atmospheric investigations. The term sonar is also used for the
equipment used to generate and receive the sound. The acoustic
frequencies used in sonar systems vary from very low (infrasonic) to
extremely high (ultrasonic). The study of underwater sound is known as
underwater acoustics .
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8. Uses of SONAR:
• It is used for communication between submerged
submarines or between a submarine and a surface
vessel
• For locating mines and underwater hazards to
navigation
• Also as a fathometer, or depth finder.
• Sonar is widely used by commercial fishermen for
locating shoals of fish.
9. • Sonar (sound navigation and ranging) has many uses. It is used by
the military to look for submarines (one of the reasons for which it
was originally developed).
• It is also used by the military and by ocean scientists to find out
the depth of water and to map the contours of the ocean bottom.
• Sonar is also used in a variety of other ways by oceanographers to
study the everything from the ocean bottom to the waves on top.
The technology can obviously be applied to the study of ocean life.
• Sonar can also be used to look "below" the ocean bottom at the
geologic structures below the ocean floor. Petrochemical explorers
and others apply this technology.
10. • Certainly sonar has gained notoriety for being useful to
find things lying on the ocean floor. (A number of famous
ships that sunk have been located with it, like Titanic.)
And it is used by fisherman for locating fish and for
mapping terrain on the bottom of lakes or offshore fishing
sites.
• Sonar is used daily in the medical world to scan the inside
of the human body and to look at unborn babies. Medical
imaging is the most popular application of sonar.
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16. Question 2
Q2:What is the full form of SONAR?
Sound Or Navigation And Ranging.
Sound Of Navigation And Rating.
SOund Navigation And Ranging.
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19. Question 3
Q3:What is ‘echocardiography’ ?
Ultrasonic waves are made to pass in the heart.
Ultrasonic waves are made to reflect from the heart
to form the image of the heart.
Ultrasonic waves are passed through the stomach to
view the inside content.
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