OPES OF ULTRASOUND
ERCEPTION IN HUMANS AND ANIMALS
ETECTION AND RANGING
•NON CONTACT CENSOR
•NON DESTRUCTIVE TESTING
•ULTRASONIC RANGE FINDING: SONAR
MAGING: MEDICAL SONOGRAPHY
BREAKING DOWN KIDNEY STONES
ULTIPLE CHOICE QUESTIONS
Ultrasound is an oscillating sound pressure wave with a frequency greater than
the upper limit of the human hearing range. 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. Ultrasound
devices operate with frequencies from 20 kHz up to several gigahertz.
Ultrasonics is the application of ultrasound.
Ultrasound can be used for medical imaging,
detection, measurement and cleaning. At
higher power levels, ultrasonics is useful for
changing the chemical properties of
Perception in humans and animals
The upper frequency limit in humans (approximately 20 kHz) is
due to limitations of the middle ear.Ultrasonic hearing can occur
if ultrasound is fed directly into the human skull and reaches the
cochlea through bone conduction, without passing through the
Children can hear some high-pitched sounds that older adults
cannot hear, because in humans the upper limit pitch of hearing
tends to decrease with age.
Some people find high-frequency sounds and ultrasound
extremely painful. This is often associated with autism
and sensory defensiveness but can also be caused by
1.Bats use a variety of ultrasonic ranging ( echolocation)
techniques to detect their prey. They can detect frequencies
beyond 100 kHz, possibly up to 200 kHz.
2.Dogs with normal hearing can hear ultrasound. A
dog whistle exploits this by emitting a high frequency sound
to call to a dog.
3.Toothed whales, including dolphins, can hear ultrasound
and use such sounds in their navigational system ( biosonar)
to orient and capture prey.
4.Porpoises have the highest known upper hearing limit, at
around 160 kHz.
5. Several types of fish can detect ultrasound. In the order
Clupeiformes, members of the subfamily Alosinae (shad), have
been shown to be able to detect sounds up to 180 kHz, while
the other subfamilies (e.g. herrings) can hear only up to
Detection and Ranging
An ultrasonic level or sensing system requires no contact
with the target. For many processes in the medical,
pharmaceutical, military and general industries this is an
advantage over inline sensors that may contaminate the
liquids inside a vessel or tube or that may be clogged by the
Ultrasonic testing is a type of nondestructive testing
commonly used to find flaws in materials and to measure
the thickness of objects.
Sonar stands for sound navigation and ranging .
A common use of ultrasound is in underwater range finding; this use
is also called Sonar. An ultrasonic pulse is generated in a particular
direction. If there is an object in the path of this pulse, part or all of
the pulse will be reflected back to the transmitter as an echo and can
be detected through the receiver path.
Medical sonography (ultrasonography) is an ultrasound-based diagnostic
medical imaging technique used to visualize muscles, tendons, and many
internal organs, to capture their size, structure and any pathological
lesions with real time tomographic images.
Breaking down kidney stones
A high powered ultrasound wave is used to break down kidney
stones and other stones in the body. The stones vibrate until
they shake themselves apart and are then easily passed out of
the body via the urethra.
Radar and ultrasonic sound waves made by dolphins Even though dolphins live in
the darkness of the sea, they can still search for food in the form of fish.
They do this by emitting sound that cannot be detected by the human ear
(ultrasonic sound waves) and catching the sound that comes back like an echo.
Even though they cannot see their food, they can tell their direction and distance by
using ultrasonic sound waves.
The way radar works and the way that dolphins use ultrasonic sound waves are
much the same.
Q1: Audible range of hearing is
a. 20Hz TO 30000Hz
b. 20Hz TO 20000Hz
c. 10Hz to 20Hz
unit of quantity on which pitch of the
sound depends is :
Q3. Nature of sound wave is :
Q4. Sound waves in air are :
(B) Radio waves
(C) Transverse waves
(D) Electromagnetic waves
Q5. In SONAR we use :
d.Audible sound waves
Q6. which kind of sound is produced in an earthquake before the
main shock wave begins?
c. Audible sound
d. None of the above
Q7. ‘Note’ is a sound:
a.Of a mixture of several frequencies
b.Of mixture of only two frequencies
c. of a single frequency
d. always unpleasant to listen to
Q8. one of the following can hear infrasound:
Q9. The ultrasound waves can penetrate into matter to a large extent because
a.Very high speed
b.Very high frequency
c. very high wavelength
d. very high amplitude
Q10. what types of waves are generated by SONAR device fixed to a fishing
b. radio waves
c. sound waves
d. infrared waves