This document discusses the phenomenon of diffraction, which refers to the bending of waves around obstacles. It provides explanations of diffraction from both classical physics and quantum mechanics perspectives. Examples of diffraction effects in everyday life are given, such as the rainbow pattern seen on CDs/DVDs. The document also covers the history of diffraction studies, analytical models used to calculate diffraction, and the role of coherence in diffraction.
Waves (Grade 7, Quarter 3) Suggested Guide for DiscussionRachel Espino
A suggested powerpoint presentation guide for discussion for Gr.7 teachers on the characteristics and categories of waves. It also includes a simple quiz (under knowledge category) as an assessment
Waves (Grade 7, Quarter 3) Suggested Guide for DiscussionRachel Espino
A suggested powerpoint presentation guide for discussion for Gr.7 teachers on the characteristics and categories of waves. It also includes a simple quiz (under knowledge category) as an assessment
Role of electromagnetic Radiation in Remote SensingNzar Braim
Role of electromagnetic Radiation in Remote Sensing
It should be clear by now that the electromagnetic waves are originator and
carrier of information in Earth observation. The information content of the products delivered by a given type of sensor is essentially related to the parameters, mainly frequency (or wavelength) and polarization, characterizing the observing system, including the geometry at which data are acquired. Therefore, the specifications of an EO system, which include the type of sensor, the band of operation, the observation angle, etc.
MAHARASHTRA STATE BOARD
CLASS XI AND XII
PHYSICS
CHAPTER 7
WAVE OPTICS
CONTENT:
Huygen's principle.
Huygen's principles & proof of laws of reflection/refraction.
Condition for construction & destruction of coherent waves.
Young's double slit experiment.
Modified Young's double slit experiment.
Intensity of light in Y.D.S.E.
Diffraction due to single slit.
Polarisation & doppler effect.
Chapters
Reminders: light
speed of light in a vacuum
A brief historical reminder of the speed of light
Invariance of the speed of light in a vacuum
Influence of the propagation medium
Speed or celerity?
Speed, distance traveled, and duration
Relations including the speed of light
Faster than light?
Speed of light: did you know?
Reminders: light
Light is an electromagnetic wave, consisting of a magnetic field and an electric field oscillating perpendicular to each other in a plane perpendicular to the direction of propagation of the light wave. In a vacuum, light travels in a straight line at the speed of light noted c.
speed of light in a vacuum
Exact value
The exact value of the speed of light was fixed in 1983 by the Bureau of Weights and Measures at c = 299 792 458 m/s or c = 2.99792458 x 10 8 m/s, using the units of the international system. It can also be expressed in kilometers per hour by multiplying the value in m/s by 3.6: c = 1,079,252,848.8 km/h or c = 1.0792528488 x 10 9 km/h. This value, which represents a fundamental constant of physics, can be used for calculations requiring great precision. It is also used to define the meter in the international system of units: one meter corresponds to the length traveled in a vacuum by light for a duration of 1/299,792,458 seconds.
A brief historical reminder of the speed of light
The first conception concerning light suppose that it can be either present in a space, or absent: the light would therefore be instantaneous. The Arab scholar Alhazen (965-1039) was interested in optics and wrote reference treatises. He is the first to have the intuition that the appearance of light is not instantaneous, that it has a speed of propagation, but he cannot prove it.
Galileo (1564-1039) tries to measure the propagation time of light between two hills using two people a few kilometers apart and equipped with clocks. He fails to measure the speed of light (which, in the context of this experiment, takes 10 -5 seconds to travel the previously defined distance, not measurable for the time) and deduces from the failure of this experiment that the speed of propagation of light is very high.
Cassini (1625-1712) speculated that the irregularity in the movement of Io, a satellite of Jupiter, could come from a delay in the arrival of light from the satellite, "such that it takes 10 or 11 minutes for it travels a distance equal to the radius of the Earth's orbit". Römer (1644-1710) explains the discrepancy between the eclipses of Io (a satellite of Jupiter) and Cassini's predictions by assuming that light has a speed of propagation. It is the first to give an order of magnitude of the speed of light.
Bradley (1693-1762) confirms Römer's hypothesis and proposes a first estimate of the speed of light at approximately 10188 times that of the rotation of the Earth around the Sun, the latter being however poorly known. His discovery is linked to the aberration of light,
Telescope history
&facts,
A detailed presentation on fraunhofer diffraction and also an introduction to the concept of diffraction.There is also a brief discussion on fresnel diffraction and the difference between former and the latter.
INTRODUCTION TO QUANTUM THEORY LIGHT AND ITS PRINCIPLES
The General Characteristics, Properties and Classification of Wave, The Nature of Light (Is that
wave? Or particle? Or Both?), Classical and Quantum Theory of Light
THE WAVE NATURE OF LIGHT
Huygens’s wave theory of light, Young’s Double Slits Experiment, and Electromagnetic waves
(Maxwell’s Electromagnetic theory of light)
PARTICLE NATURE OF LIGHT
Newton’s corpuscular theory of light and Black Body radiation, Photoelectric Effect, The
Compton Scattering Effect, X-ray and X-ray Diffraction, and The Davinson-Germer Electron
Diffraction Experiment
WAVE PARTICLE DUALITY
De-Broglie Wave length, Electron Double Slits Diffraction Experiment, and Electron
Microscope
Event Management System Vb Net Project Report.pdfKamal Acharya
In present era, the scopes of information technology growing with a very fast .We do not see any are untouched from this industry. The scope of information technology has become wider includes: Business and industry. Household Business, Communication, Education, Entertainment, Science, Medicine, Engineering, Distance Learning, Weather Forecasting. Carrier Searching and so on.
My project named “Event Management System” is software that store and maintained all events coordinated in college. It also helpful to print related reports. My project will help to record the events coordinated by faculties with their Name, Event subject, date & details in an efficient & effective ways.
In my system we have to make a system by which a user can record all events coordinated by a particular faculty. In our proposed system some more featured are added which differs it from the existing system such as security.
COLLEGE BUS MANAGEMENT SYSTEM PROJECT REPORT.pdfKamal Acharya
The College Bus Management system is completely developed by Visual Basic .NET Version. The application is connect with most secured database language MS SQL Server. The application is develop by using best combination of front-end and back-end languages. The application is totally design like flat user interface. This flat user interface is more attractive user interface in 2017. The application is gives more important to the system functionality. The application is to manage the student’s details, driver’s details, bus details, bus route details, bus fees details and more. The application has only one unit for admin. The admin can manage the entire application. The admin can login into the application by using username and password of the admin. The application is develop for big and small colleges. It is more user friendly for non-computer person. Even they can easily learn how to manage the application within hours. The application is more secure by the admin. The system will give an effective output for the VB.Net and SQL Server given as input to the system. The compiled java program given as input to the system, after scanning the program will generate different reports. The application generates the report for users. The admin can view and download the report of the data. The application deliver the excel format reports. Because, excel formatted reports is very easy to understand the income and expense of the college bus. This application is mainly develop for windows operating system users. In 2017, 73% of people enterprises are using windows operating system. So the application will easily install for all the windows operating system users. The application-developed size is very low. The application consumes very low space in disk. Therefore, the user can allocate very minimum local disk space for this application.
NO1 Uk best vashikaran specialist in delhi vashikaran baba near me online vas...Amil Baba Dawood bangali
Contact with Dawood Bhai Just call on +92322-6382012 and we'll help you. We'll solve all your problems within 12 to 24 hours and with 101% guarantee and with astrology systematic. If you want to take any personal or professional advice then also you can call us on +92322-6382012 , ONLINE LOVE PROBLEM & Other all types of Daily Life Problem's.Then CALL or WHATSAPP us on +92322-6382012 and Get all these problems solutions here by Amil Baba DAWOOD BANGALI
#vashikaranspecialist #astrologer #palmistry #amliyaat #taweez #manpasandshadi #horoscope #spiritual #lovelife #lovespell #marriagespell#aamilbabainpakistan #amilbabainkarachi #powerfullblackmagicspell #kalajadumantarspecialist #realamilbaba #AmilbabainPakistan #astrologerincanada #astrologerindubai #lovespellsmaster #kalajaduspecialist #lovespellsthatwork #aamilbabainlahore#blackmagicformarriage #aamilbaba #kalajadu #kalailam #taweez #wazifaexpert #jadumantar #vashikaranspecialist #astrologer #palmistry #amliyaat #taweez #manpasandshadi #horoscope #spiritual #lovelife #lovespell #marriagespell#aamilbabainpakistan #amilbabainkarachi #powerfullblackmagicspell #kalajadumantarspecialist #realamilbaba #AmilbabainPakistan #astrologerincanada #astrologerindubai #lovespellsmaster #kalajaduspecialist #lovespellsthatwork #aamilbabainlahore #blackmagicforlove #blackmagicformarriage #aamilbaba #kalajadu #kalailam #taweez #wazifaexpert #jadumantar #vashikaranspecialist #astrologer #palmistry #amliyaat #taweez #manpasandshadi #horoscope #spiritual #lovelife #lovespell #marriagespell#aamilbabainpakistan #amilbabainkarachi #powerfullblackmagicspell #kalajadumantarspecialist #realamilbaba #AmilbabainPakistan #astrologerincanada #astrologerindubai #lovespellsmaster #kalajaduspecialist #lovespellsthatwork #aamilbabainlahore #Amilbabainuk #amilbabainspain #amilbabaindubai #Amilbabainnorway #amilbabainkrachi #amilbabainlahore #amilbabaingujranwalan #amilbabainislamabad
Industrial Training at Shahjalal Fertilizer Company Limited (SFCL)MdTanvirMahtab2
This presentation is about the working procedure of Shahjalal Fertilizer Company Limited (SFCL). A Govt. owned Company of Bangladesh Chemical Industries Corporation under Ministry of Industries.
Water scarcity is the lack of fresh water resources to meet the standard water demand. There are two type of water scarcity. One is physical. The other is economic water scarcity.
Courier management system project report.pdfKamal Acharya
It is now-a-days very important for the people to send or receive articles like imported furniture, electronic items, gifts, business goods and the like. People depend vastly on different transport systems which mostly use the manual way of receiving and delivering the articles. There is no way to track the articles till they are received and there is no way to let the customer know what happened in transit, once he booked some articles. In such a situation, we need a system which completely computerizes the cargo activities including time to time tracking of the articles sent. This need is fulfilled by Courier Management System software which is online software for the cargo management people that enables them to receive the goods from a source and send them to a required destination and track their status from time to time.
Cosmetic shop management system project report.pdfKamal Acharya
Buying new cosmetic products is difficult. It can even be scary for those who have sensitive skin and are prone to skin trouble. The information needed to alleviate this problem is on the back of each product, but it's thought to interpret those ingredient lists unless you have a background in chemistry.
Instead of buying and hoping for the best, we can use data science to help us predict which products may be good fits for us. It includes various function programs to do the above mentioned tasks.
Data file handling has been effectively used in the program.
The automated cosmetic shop management system should deal with the automation of general workflow and administration process of the shop. The main processes of the system focus on customer's request where the system is able to search the most appropriate products and deliver it to the customers. It should help the employees to quickly identify the list of cosmetic product that have reached the minimum quantity and also keep a track of expired date for each cosmetic product. It should help the employees to find the rack number in which the product is placed.It is also Faster and more efficient way.
Saudi Arabia stands as a titan in the global energy landscape, renowned for its abundant oil and gas resources. It's the largest exporter of petroleum and holds some of the world's most significant reserves. Let's delve into the top 10 oil and gas projects shaping Saudi Arabia's energy future in 2024.
Forklift Classes Overview by Intella PartsIntella Parts
Discover the different forklift classes and their specific applications. Learn how to choose the right forklift for your needs to ensure safety, efficiency, and compliance in your operations.
For more technical information, visit our website https://intellaparts.com
Quality defects in TMT Bars, Possible causes and Potential Solutions.PrashantGoswami42
Maintaining high-quality standards in the production of TMT bars is crucial for ensuring structural integrity in construction. Addressing common defects through careful monitoring, standardized processes, and advanced technology can significantly improve the quality of TMT bars. Continuous training and adherence to quality control measures will also play a pivotal role in minimizing these defects.
Quality defects in TMT Bars, Possible causes and Potential Solutions.
Report cover
1. Systems & Biomedical Engineering Department
Physical optics
Project on waves diffraction
Presented for : ph Mohammed Hesham
Presented by : Abdelrhman Aboubakr
Section : 1
Bench Number: 42
2. Diffraction :
Diffraction pattern of red laser beam made
on a plate after passing through a small
circular aperture in another plate
Diffraction refers to various phenomena
that occur when a wave encounters an
obstacle or a slit. It is defined as the
bending of waves around the corners of an
obstacle or aperture into the region of
geometrical shadow of the obstacle. In
classical physics, the diffraction
phenomenon is described as the
interference of waves according to the
Huygens–Fresnel principle that treats each
point in the wave-front as a collection of
individual spherical wavelets. These
characteristic behaviors are exhibited when
3. a wave encounters an obstacle or a slit that
is comparable in size to its wavelength.
Similar effects occur when a light wave
travels through a medium with a varying
refractive index, or when a sound wave
travels through a medium with varying
acoustic impedance. Diffraction has an
impact on the acoustic space. Diffraction
occurs with all waves, including sound
waves, water waves, and electromagnetic
waves such as visible light, X-rays and radio
waves.
Since physical objects have wave-like
properties (significantly at the atomic level,
invisibly at macro level), diffraction also
occurs with matter and can be studied
according to the principles of quantum
mechanics. Italian scientist Francesco Maria
Grimaldi coined the word "diffraction" and
4. was the first to record accurate
observations of the phenomenon in 1660.
While diffraction occurs whenever
propagating waves encounter such changes,
its effects are generally most pronounced
for waves whose wavelength is roughly
comparable to the dimensions of the
diffracting object or slit. If the obstructing
object provides multiple, closely spaced
openings, a complex pattern of varying
intensity can result. This is due to the
addition, or interference, of different parts
of a wave that travel to the observer by
different paths, where different path
lengths result in different phases (see
diffraction grating and wave superposition).
The formalism of diffraction can also
describe the way in which waves of finite
extent propagate in free space. For
5. example, the expanding profile of a laser
beam, the beam shape of a radar antenna
and the field of view of an ultrasonic
transducer can all be analyzed using
diffraction equations.
Application :
The effects of diffraction are often seen in
everyday life. The most striking examples of
diffraction are those that involve light; for
example, the closely spaced tracks on a CD
or DVD act as a diffraction grating to form
the familiar rainbow pattern seen when
looking at a disc. This principle can be
extended to engineer a grating with a
structure such that it will produce any
diffraction pattern desired; the hologram
on a credit card is an example. Diffraction in
6. the atmosphere by small particles can cause
a bright ring to be visible around a bright
light source like the sun or the moon. A
shadow of a solid object, using light from a
compact source, shows small fringes near
its edges. The speckle pattern which is
observed when laser light falls on an
optically rough surface is also a diffraction
phenomenon. When deli meat appears to
be iridescent, that is diffraction off the meat
fibers.All these effects are a consequence of
the fact that light propagates as a wave.
Diffraction can occur with any kind of wave.
Ocean waves diffract around jetties and
other obstacles. Sound waves can diffract
around objects, which is why one can still
hear someone calling even when hiding
behind a tree. Diffraction can also be a
concern in some technical applications; it
7. sets a fundamental limit to the resolution of
a camera, telescope, or microscope.
History :
The effects of diffraction of light were first
carefully observed and characterized by
Francesco Maria Grimaldi, who also coined
the term diffraction, from the Latin
diffringere, 'to break into pieces', referring
to light breaking up into different
directions. The results of Grimaldi's
observations were published posthumously
in 1665.Isaac Newton studied these effects
and attributed them to inflexion of light
rays. James Gregory (1638–1675) observed
the diffraction patterns caused by a bird
feather, which was effectively the first
diffraction grating to be discovered. Thomas
Young performed a celebrated experiment
8. in 1803 demonstrating interference from
two closely spaced slits. Explaining his
results by interference of the waves
emanating from the two different slits, he
deduced that light must propagate as
waves. Augustin-Jean Fresnel did more
definitive studies and calculations of
diffraction, made public in 1815 and 1818,
and thereby gave great support to the wave
theory of light that had been advanced by
Christiaan Huygens[13] and reinvigorated
by Young, against Newton's particle theory.
Mechanism:
In traditional classical physics diffraction
arises because of the way in which waves
propagate; this is described by the
Huygens–Fresnel principle and the principle
of superposition of waves. The propagation
9. of a wave can be visualized by considering
every particle of the transmitted medium
on a wavefront as a point source for a
secondary spherical wave. The wave
displacement at any subsequent point is the
sum of these secondary waves. When
waves are added together, their sum is
determined by the relative phases as well as
the amplitudes of the individual waves so
that the summed amplitude of the waves
can have any value between zero and the
sum of the individual amplitudes. Hence,
diffraction patterns usually have a series of
maxima and minima.
In the modern quantum mechanical
understanding of light propagation through
a slit (or slits) every photon has what is
known as a wavefunction which describes
its path from the emitter through the slit to
10. the screen. The wavefunction (the path the
photon will take) is determined by the
physical surroundings such as slit geometry,
screen distance and initial conditions when
the photon is created. In important
experiments (A low-intensity double-slit
experiment was first performed by G. I.
Taylor in 1909, see double-slit experiment)
the existence of the photon's wavefunction
was demonstrated. In the quantum
approach the diffraction pattern is created
by the distribution of paths, the observation
of light and dark bands is the presence or
absence of photons in these areas (no
interference!). The quantum approach has
some striking similarities to the
Huygens-Fresnel principle, in that principle
the light becomes a series of individually
distributed light sources across the slit
11. which is similar to the limited number of
paths (or wave functions) available for the
photons to travel through the slit.
There are various analytical models which
allow the diffracted field to be calculated,
including the Kirchhoff-Fresnel diffraction
equation which is derived from wave
equation, the Fraunhofer diffraction
approximation of the Kirchhoff equation
which applies to the far field and the
Fresnel diffraction approximation which
applies to the near field. Most
configurations cannot be solved analytically,
but can yield numerical solutions through
finite element and boundary element
methods.
It is possible to obtain a qualitative
understanding of many diffraction
phenomena by considering how the relative
12. phases of the individual secondary wave
sources vary, and in particular, the
conditions in which the phase difference
equals half a cycle in which case waves will
cancel one another out.
The simplest descriptions of diffraction are
those in which the situation can be reduced
to a two-dimensional problem. For water
waves, this is already the case; water waves
propagate only on the surface of the water.
For light, we can often neglect one direction
if the diffracting object extends in that
direction over a distance far greater than
the wavelength. In the case of light shining
through small circular holes we will have to
take into account the full three-dimensional
nature of the problem.
Examples :
13. ·Single-slit diffraction
·Diffraction grating
·Circular aperture
·General aperture
·Propagation of a laser beam
·Diffraction-limited imaging
·Speckle patterns
Coherence:
The description of diffraction relies on the
interference of waves emanating from the
same source taking different paths to the
same point on a screen. In this description,
the difference in phase between waves that
took different paths is only dependent on
the effective path length. This does not take
14. into account the fact that waves that arrive
at the screen at the same time were
emitted by the source at different times.
The initial phase with which the source
emits waves can change over time in an
unpredictable way. This means that waves
emitted by the source at times that are too
far apart can no longer form a constant
interference pattern since the relation
between their phases is no longer time
independent.
The length over which the phase in a beam
of light is correlated, is called the coherence
length. In order for interference to occur,
the path length difference must be smaller
than the coherence length. This is
sometimes referred to as spectral
coherence, as it is related to the presence
of different frequency components in the
15. wave. In the case of light emitted by an
atomic transition, the coherence length is
related to the lifetime of the excited state
from which the atom made its transition.
If waves are emitted from an extended
source, this can lead to incoherence in the
transversal direction. When looking at a
cross section of a beam of light, the length
over which the phase is correlated is called
the transverse coherence length. In the
case of Young's double slit experiment, this
would mean that if the transverse
coherence length is smaller than the
spacing between the two slits, the resulting
pattern on a screen would look like two
single slit diffraction patterns.
In the case of particles like electrons,
neutrons and atoms, the coherence length
16. is related to the spatial extent of the wave
function that describes the particle.
References:
●Wireless Communications: Principles
and Practice, Prentice Hall
communications engineering and
emerging technologies series
●"A History of Physics in its Elementary
Branches, including the evolution of
physical laboratories."
●Andrew Norton (2000). Dynamic fields
and waves of physics
17. ●The complete version of Fresnel's paper
on diffraction was published in 1821.
Table Of Contents:
1.Diffraction
2.Applications
3.History
4.Mechanism
5.Examples
6.Coherence
7.References