Sound is produced by vibration and needs a medium to travel through. It propagates as longitudinal waves of alternating compressions and rarefactions. The human range of hearing is between 20 Hz to 20 kHz. Ultrasound above this range has many applications like cleaning, object detection and medical imaging. Sonar uses ultrasound to detect underwater objects by calculating the time taken for echoes to return. The human ear collects sound via the outer ear and transmits it through the middle ear bones to the inner ear where it is converted to electrical signals for the brain to interpret as sound.
this chapter is nice for us as it is important in my life and please like it or it will be very usefull of you and pls like share comment and plese follow and dowload .
this chapter is nice for us as it is important in my life and please like it or it will be very usefull of you and pls like share comment and plese follow and dowload .
A powerpoint explaining what sound waves are, the equation used to calculate displacement, the equation used to calculate pressure and the equation for intensity.
Sound waves are produced by the vibration of material objects. A disturbance in the form of a longitudinal wave travels away from the vibrating source. High-pitched sounds are produced by sources vibrating at high frequency, while low-pitched sounds are produced by low-frequency sources Sound waves consist of traveling pulses of high-pressure zones, or compression, alternating with pulses of low-pressures zones, or rarefaction. Sound can travel through gases, liquids, and solid, but not through a vacuum.
a ppt on sound
includes- what is sound
production of sound
propagation of sound
characteristics of sound
reflection of sound
applications of reflection of sound
range of frequencies
ultrasound and its 8 usages
hope it helpful :D
Complete and comprehensive study of the entire chapter with attractive pictorial representation of topic being discussed and Studied. Ideal material for students to get a gist of the entire Chapter, make projects, complete ppt slide presentation for self study and group discussion.
A powerpoint explaining what sound waves are, the equation used to calculate displacement, the equation used to calculate pressure and the equation for intensity.
Sound waves are produced by the vibration of material objects. A disturbance in the form of a longitudinal wave travels away from the vibrating source. High-pitched sounds are produced by sources vibrating at high frequency, while low-pitched sounds are produced by low-frequency sources Sound waves consist of traveling pulses of high-pressure zones, or compression, alternating with pulses of low-pressures zones, or rarefaction. Sound can travel through gases, liquids, and solid, but not through a vacuum.
a ppt on sound
includes- what is sound
production of sound
propagation of sound
characteristics of sound
reflection of sound
applications of reflection of sound
range of frequencies
ultrasound and its 8 usages
hope it helpful :D
Complete and comprehensive study of the entire chapter with attractive pictorial representation of topic being discussed and Studied. Ideal material for students to get a gist of the entire Chapter, make projects, complete ppt slide presentation for self study and group discussion.
Embracing GenAI - A Strategic ImperativePeter Windle
Artificial Intelligence (AI) technologies such as Generative AI, Image Generators and Large Language Models have had a dramatic impact on teaching, learning and assessment over the past 18 months. The most immediate threat AI posed was to Academic Integrity with Higher Education Institutes (HEIs) focusing their efforts on combating the use of GenAI in assessment. Guidelines were developed for staff and students, policies put in place too. Innovative educators have forged paths in the use of Generative AI for teaching, learning and assessments leading to pockets of transformation springing up across HEIs, often with little or no top-down guidance, support or direction.
This Gasta posits a strategic approach to integrating AI into HEIs to prepare staff, students and the curriculum for an evolving world and workplace. We will highlight the advantages of working with these technologies beyond the realm of teaching, learning and assessment by considering prompt engineering skills, industry impact, curriculum changes, and the need for staff upskilling. In contrast, not engaging strategically with Generative AI poses risks, including falling behind peers, missed opportunities and failing to ensure our graduates remain employable. The rapid evolution of AI technologies necessitates a proactive and strategic approach if we are to remain relevant.
Instructions for Submissions thorugh G- Classroom.pptxJheel Barad
This presentation provides a briefing on how to upload submissions and documents in Google Classroom. It was prepared as part of an orientation for new Sainik School in-service teacher trainees. As a training officer, my goal is to ensure that you are comfortable and proficient with this essential tool for managing assignments and fostering student engagement.
Francesca Gottschalk - How can education support child empowerment.pptxEduSkills OECD
Francesca Gottschalk from the OECD’s Centre for Educational Research and Innovation presents at the Ask an Expert Webinar: How can education support child empowerment?
A Strategic Approach: GenAI in EducationPeter Windle
Artificial Intelligence (AI) technologies such as Generative AI, Image Generators and Large Language Models have had a dramatic impact on teaching, learning and assessment over the past 18 months. The most immediate threat AI posed was to Academic Integrity with Higher Education Institutes (HEIs) focusing their efforts on combating the use of GenAI in assessment. Guidelines were developed for staff and students, policies put in place too. Innovative educators have forged paths in the use of Generative AI for teaching, learning and assessments leading to pockets of transformation springing up across HEIs, often with little or no top-down guidance, support or direction.
This Gasta posits a strategic approach to integrating AI into HEIs to prepare staff, students and the curriculum for an evolving world and workplace. We will highlight the advantages of working with these technologies beyond the realm of teaching, learning and assessment by considering prompt engineering skills, industry impact, curriculum changes, and the need for staff upskilling. In contrast, not engaging strategically with Generative AI poses risks, including falling behind peers, missed opportunities and failing to ensure our graduates remain employable. The rapid evolution of AI technologies necessitates a proactive and strategic approach if we are to remain relevant.
Palestine last event orientationfvgnh .pptxRaedMohamed3
An EFL lesson about the current events in Palestine. It is intended to be for intermediate students who wish to increase their listening skills through a short lesson in power point.
The Roman Empire A Historical Colossus.pdfkaushalkr1407
The Roman Empire, a vast and enduring power, stands as one of history's most remarkable civilizations, leaving an indelible imprint on the world. It emerged from the Roman Republic, transitioning into an imperial powerhouse under the leadership of Augustus Caesar in 27 BCE. This transformation marked the beginning of an era defined by unprecedented territorial expansion, architectural marvels, and profound cultural influence.
The empire's roots lie in the city of Rome, founded, according to legend, by Romulus in 753 BCE. Over centuries, Rome evolved from a small settlement to a formidable republic, characterized by a complex political system with elected officials and checks on power. However, internal strife, class conflicts, and military ambitions paved the way for the end of the Republic. Julius Caesar’s dictatorship and subsequent assassination in 44 BCE created a power vacuum, leading to a civil war. Octavian, later Augustus, emerged victorious, heralding the Roman Empire’s birth.
Under Augustus, the empire experienced the Pax Romana, a 200-year period of relative peace and stability. Augustus reformed the military, established efficient administrative systems, and initiated grand construction projects. The empire's borders expanded, encompassing territories from Britain to Egypt and from Spain to the Euphrates. Roman legions, renowned for their discipline and engineering prowess, secured and maintained these vast territories, building roads, fortifications, and cities that facilitated control and integration.
The Roman Empire’s society was hierarchical, with a rigid class system. At the top were the patricians, wealthy elites who held significant political power. Below them were the plebeians, free citizens with limited political influence, and the vast numbers of slaves who formed the backbone of the economy. The family unit was central, governed by the paterfamilias, the male head who held absolute authority.
Culturally, the Romans were eclectic, absorbing and adapting elements from the civilizations they encountered, particularly the Greeks. Roman art, literature, and philosophy reflected this synthesis, creating a rich cultural tapestry. Latin, the Roman language, became the lingua franca of the Western world, influencing numerous modern languages.
Roman architecture and engineering achievements were monumental. They perfected the arch, vault, and dome, constructing enduring structures like the Colosseum, Pantheon, and aqueducts. These engineering marvels not only showcased Roman ingenuity but also served practical purposes, from public entertainment to water supply.
June 3, 2024 Anti-Semitism Letter Sent to MIT President Kornbluth and MIT Cor...Levi Shapiro
Letter from the Congress of the United States regarding Anti-Semitism sent June 3rd to MIT President Sally Kornbluth, MIT Corp Chair, Mark Gorenberg
Dear Dr. Kornbluth and Mr. Gorenberg,
The US House of Representatives is deeply concerned by ongoing and pervasive acts of antisemitic
harassment and intimidation at the Massachusetts Institute of Technology (MIT). Failing to act decisively to ensure a safe learning environment for all students would be a grave dereliction of your responsibilities as President of MIT and Chair of the MIT Corporation.
This Congress will not stand idly by and allow an environment hostile to Jewish students to persist. The House believes that your institution is in violation of Title VI of the Civil Rights Act, and the inability or
unwillingness to rectify this violation through action requires accountability.
Postsecondary education is a unique opportunity for students to learn and have their ideas and beliefs challenged. However, universities receiving hundreds of millions of federal funds annually have denied
students that opportunity and have been hijacked to become venues for the promotion of terrorism, antisemitic harassment and intimidation, unlawful encampments, and in some cases, assaults and riots.
The House of Representatives will not countenance the use of federal funds to indoctrinate students into hateful, antisemitic, anti-American supporters of terrorism. Investigations into campus antisemitism by the Committee on Education and the Workforce and the Committee on Ways and Means have been expanded into a Congress-wide probe across all relevant jurisdictions to address this national crisis. The undersigned Committees will conduct oversight into the use of federal funds at MIT and its learning environment under authorities granted to each Committee.
• The Committee on Education and the Workforce has been investigating your institution since December 7, 2023. The Committee has broad jurisdiction over postsecondary education, including its compliance with Title VI of the Civil Rights Act, campus safety concerns over disruptions to the learning environment, and the awarding of federal student aid under the Higher Education Act.
• The Committee on Oversight and Accountability is investigating the sources of funding and other support flowing to groups espousing pro-Hamas propaganda and engaged in antisemitic harassment and intimidation of students. The Committee on Oversight and Accountability is the principal oversight committee of the US House of Representatives and has broad authority to investigate “any matter” at “any time” under House Rule X.
• The Committee on Ways and Means has been investigating several universities since November 15, 2023, when the Committee held a hearing entitled From Ivory Towers to Dark Corners: Investigating the Nexus Between Antisemitism, Tax-Exempt Universities, and Terror Financing. The Committee followed the hearing with letters to those institutions on January 10, 202
2. कारणाभावात् कायार्याभाव: |
न तु कायार्याभावातु कारणाभाव: ||
(vaiseshikadarshaanam 1.2)
There is no effect possible without a cause.
But the absence of effect does not means the
absence of causes.
The text also substantistes the above fact with
an example:Applying a force (less than needed
to overcome friction ) will not make a body
move.In the case , (The force ) is present but
not the effect (Motion)
3. 1) Production of sound :-
Sound is produced due to the vibration of objects.
Vibration is the rapid to and fro motion of an object.
Eg :- The sound of human voice is produced due to the
vibration of the vocal cords.
A stretched rubber band when plucked vibrates and
produces sound.
Activity :- Strike the prongs of a tuning
fork on a rubber pad and bring it near
the ear. We can hear a sound. If a
suspended table tennis ball is touched
with the vibrating prong, the ball is
pushed away repeatedly. This shows
that the prong is vibrating and
vibrating objects produces sound.
Thread
Vibrating
tuning fork
Table tennis
ball
4. 2) Propagation of sound :-
The sound produced by a vibrating object travels through a
medium to a listener. The medium can be solid, liquid or gas.
When an object vibrates, the particles around the medium vibrates.
The particle in contact with the vibrating object is first displaced from
its equilibrium position. It then exerts a force on the adjacent particle
and the adjacent particle is displaced from its position of rest. After
displacing the adjacent particle the first particle comes back to its
original position. This process repeats in the medium till the sound
reaches the ear.
The disturbance produced by the vibrating body travels through the
medium but the particles do not move forward themselves.
A wave is a disturbance which moves through a medium by the
vibration of the particles of the medium. So sound is considered as a
wave. Since sound waves are produced due to the vibration of
particles of the medium sound waves are called mechanical waves.
5. Propagation of sound through air :-
Air is the most common medium through which sound travels.
When a vibrating object moves forward, it pushes and compresses the
air in front of it forming a region of high pressure called compression
(C). The compression moves away from the vibrating object. When the
vibrating object moves backward, it forms a region of low pressure
called rarefaction (R). As the object moves to and fro rapidly, it
produces a series of compressions and rarefaction in the air which
makes the sound to propagate in the medium.
6. A vibrating object producing a series of compressions (C)
and rarefaction (R)
C C C CRR R R
7. 3) Sound needs a medium to travel :-
Sound is a mechanical wave and needs a medium for propagation.
Sound travels through solids, liquids and gases. Sound does not travel
in vacuum.
Activity:-
Suspend an electric bell in an air tight bell jar. Connect the bell jar to
a vacuum pump. If the switch is pressed, we can hear the sound of the
bell. If air is pumped out through the vacuum pump, we cannot hear the
sound of the bell. This shows that sound needs a medium to travel and
sound cannot travel in vacuum.
Bell jar
Electric bell
Cork
8. 4) Sound waves are longitudinal waves :-
Sound propagates in a medium as a series of compressions (C) and
rarefactions (R).
In these waves the particles move back and forth parallel to the
direction of propagation of the disturbance. Such waves are called
longitudinal waves.
There is another kind of waves called transverse waves. In these
waves the particles oscillate up and down perpendicular to the
propagation of the direction of disturbance.
Activity :- Stretch a slinky and push and pull it alternately at one end.
If you mark a dot on the slinky, the dot moves back and forth parallel to
the direction of the propagation of the disturbance.
C C CR R R
9. 5) Characteristics of a sound wave :-
Sound wave can be described by its frequency, amplitude and speed.
Sound can be graphically represented as a wave. There is changes in
the density and pressure as sound moves in a medium.
Compressions are the regions of high pressure and density where
the particles are crowded and are represented by the upper portion of
the curve called crest.
Rarefactions are the regions of low pressure and density where the
particles are spread out and are represented by the lower portion of the
curve called trough.
The distance between two consecutive compressions (crests) or two
consecutive troughs is called wave length. It is represented by the
symbol . (Greek letter lamda). Its SI unit is metre (m).
compression rarefaction
Crest
Troug
h
λλ
PressureorDensity
λ
10. i) Frequency of sound wave :-
When sound is propagated through a medium, the density of the
medium oscillates between a maximum value and a minimum value.
The change in the density of the medium from a maximum value to a
minimum value and again to the maximum value is one oscillation.
The number of oscillations per unit time is called the frequency of
the sound wave.
It is represented by the symbol ٧ (Greek letter nu).
Its SI unit is hertz (Hz).
11. ii) Time period of sound wave :-
The time taken for the change in the density of the medium from a
maximum value to a minimum value and again to the maximum value
is the time period of the sound wave.
Or
The time taken for one complete oscillation in the density of the
medium is called the time period of the sound wave.
It is represented by the letter T.
The SI unit is second (s).
Frequency and time are represented as follows :-
٧ for one oscillation
1 1
T = ---- or ٧ = ----
٧ T
12. iii) Amplitude of sound wave :-
The magnitude of the maximum disturbance in the medium on either
side of the mean value is the amplitude of the sound wave.
Or
The amplitude of sound wave is the height of the crest or tough.
It is represented by the letter A.
The SI unit is the same as that of density or pressure.
Wavelength and Amplitude
The wavelength is the distance between the "crests" of two waves that are next to
each other. The amplitude is how high the crests are.
Wavedisturbance
13. iv) Pitch and loudness of sound :-
The pitch of sound (shrillness or flatness) depends on
the frequency of vibration.
If the frequency is high, the sound has high pitch and if
the frequency is low, the sound has low pitch.
Wavelength, Frequency, and Pitch
Since the sounds are travelling at about the same speed, the one with the shorter wavelength
will go by more frequently; it has a higher frequency, or pitch. In other words, it sounds higher.
14. The loudness of sound depends upon the amplitude of
vibration.
If the amplitude is bigger, the sound is loud and if the
amplitude is smaller, the sound is soft.
Amplitude is Loudness
The size of a wave (how much it is "piled up" at the high points) is its amplitude. For
sound waves, the bigger the amplitude, the louder the sound.
15. v) Speed of sound :-
The speed of sound is different in different media. The speed of
sound is more in solids, less in liquids and least in gases.
The speed of sound also depends on the temperature of the medium.
If the temperature of the medium is more, the speed of sound is more.
Speed of sound in different media at 250
C.
Relationship between
Speed (v), frequency
(٧) and wave length
(λ)
Speed = wave length x
frequency
v = λ x ٧
State Substance Speed in m/s
Solid Aluminium 6420
Steel 5960
Iron 5950
Brass 4700
Glass 3980
Liquid Water (Sea) 1531
Water (Distilled) 1498
Ethanol 1207
Methanol 1103
Gas Hydrogen 1284
Helium 965
Air 346
Oxygen 316
Sulphur dioxide 213
16. 6) Reflection of sound :-
Like light, sound gets reflected at the surface of a solid or liquid and
follows the laws of reflection.
i) The angle of incidence is equal to the angle of reflection.
ii) The incident ray, the reflected ray and normal at the point of
incidence all lie in the same plane.
Activity :- Take two pipes of the same length and arrange them on a
table near a wall or metal plate. Keep a clock near the open end of one
pipe and try to hear the sound of the clock through the other pipe by
adjusting the position of the pipe.
Now measure the angles of incidence
and reflection. Then lift the second
pipe and try to hear the sound.
It will be seen that the angle of
incidence is equal to the angle of
reflection. The incident ray, the
reflected ray and normal all lie in
the same plane.
17. 7a) Echo :-
If we shout or clap near a reflecting surface like tall building or a
mountain, we hear the same sound again. This sound which we hear is
called echo. It is caused due to the reflection of sound.
To hear an echo clearly, the time interval between the original
sound and the echo must be at least 0.1 s.
Since the speed of sound in air is 344 m/s, the distance travelled by
sound in 0.I s = 344 m/s x 0.1 s = 34.4 m
So to hear an echo clearly, the minimum distance of the reflecting
surface should be half this distance, that is 17.2 m.
b) Reverberation :-
Echoes may be heard more than once due to repeated or multiple
reflections of sound from several reflecting surfaces. This causes
persistence of sound called reverberation.
In big halls or auditoriums to reduce reverberation, the roofs and
walls are covered by sound absorbing materials like compressed fibre
boards, rough plaster or draperies.
18. c) Uses of multiple reflection of sound :-
i) Megaphones, horns, musical instruments like trumpets, shehnais
etc. are deigned to send sound by multiple reflection in a particular
direction without spreading in all directions.
ii) Doctors listen to sounds from the human body through a
stethoscope. The sound of heartbeat reaches the doctor’s ears by
multiple reflection.
iii) Generally the ceilings of cinema halls and auditoriums are curved
so that sound after multiple reflection reaches all parts of the hall.
Sometimes a curved sound board is placed behind the stage so
that
sound after multiple reflection spreads evenly across the hall.
19. 8) Range of Hearing :-
Human beings can hear sound frequencies between 20
Hz and 2000 Hz.
Sound whose frequency is less than 20 Hz is called
infrasonic sound. Animals like dogs, elephants, rhinoceros,
whales etc. produce and hear infrasonic sound.
Sound whose frequency is more than 2000 Hz is called
ultrasonic sound. Animals like dolphins, bats, rats
propoises etc. produce and hear ultrasonic sound.
Bats use reflection of ultrasonic sound waves to detect an
obstacle or its prey.
20. 9) Uses of ultrasonic sound :-
i) Ultrasonic sound is used to clean objects like electronic
components. The components to be cleaned are kept in a
cleaning solution and ultrasonic waves are sent into the
solution. Due to the high frequency, the dirt particles get
detached from the components.
ii) Ultrasonic sound is used to detect cracks in metal
blocks. Ultrasonic waves are sent through the metal
blocks and if there are cracks, the waves are reflected
back and the cracks can be detected.
iii) Ultrasonic sound is used in ultra sound scanners for
getting images of internal organs of the human body.
iv) Ultrasonic sound is used to break small stones formed in
the kidneys into fine grains so that they are removed
through the urine.
21. 10) SONAR :-
Sonar stands for Sound Navigation And Ranging. It is a device which
uses ultrasonic waves to measure distance, direction and speed of
underwater objects.
Sonar has a transmitter and a detector installed in ships. The
transmitter produces ultrasonic sound waves which travel through the
water and after striking the object in the sea bed is reflected back to the
detector.
The distance of the object can be calculated by knowing the speed of
sound in water and the time taken between the transmission and
reception of ultrasound.
If the time taken for the transmission and reception of ultra sound is t
and the distance travelled is 2d by the ultra sound, then 2d = v x t
or d = v x t
2
22. 11) Structure of the human ear :-
The outer ear called pinna collects the sound waves. The sound
waves passes through the ear canal to a thin membrane called eardrum.
The eardrum vibrates. The vibrations are amplified by the three bones
of the middle ear called hammer, anvil and stirrup. The middle ear then
transmits the sound waves to the inner ear. In the inner ear the sound
waves are converted into electrical signals by the cochlea and sent to
the brain through the auditory nerves. The brain then interprets the
signals as sound.
Hammer
Anvil
Stirrup Cochlea
Pinna