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PROPAGATION OF WAV
Presented To: Ms. Papiya Bhowmik Presented By: Utkarsh AbhishuVipul KhandelwTarun Raj Singh
Tarkeshwar Gu
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ContentsWave and wave propaga
tion.
Classification of waves according to propagation.
Longitudinal Wave
Transverse Wave
Fluids and transverse wave
Mechanical Wave
Electromagnetic Wave
Electromagnetic Propagation
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Waves
A wave is a disturbance or oscillation that travels through sp
matter, accompanied by a transfer of energy.
Transfers energy from one point to another without per
displacement of mediumsparticle.
Wave propagation is any of the ways in which waves travel.
With respect to the direction of the oscillation relative
propagation direction, we can distinguish between long
wave and transverse waves.
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Classification of waves
According to propagation
On the basis of direction of propagation relative to oscillation:
Longitudinal Wave
Transverse Wave
On the basis of medium of propagation:
Mechanical Waves
Electromagnetic Waves
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Longitudinal Wave
A longitudinal wave is a wave in which particles of the medium
direction parallel to the direction that the wave moves.
A sound wave traveling through air is a classic example of a
wave. As a sound wave moves from the lips of a speaker to t
listener, particles of air vibrate back and forth in the same direct
opposite direction of energy transport.
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Examples
Sound wave through ai
Longitudinal oscillation of spring
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Transverse Wave
A transverse waveis a wave in which particles of the medium m
a direction perpendicular to the direction that the wave moves
A slinky is stretched out in a horizontal direction and p
introduced into the slinky on the left end by vibrating the first
and down then energy will begin to be transported through thefrom left to right. As the energy is transported from left to rig
individual coils of the medium will be displaced upward
downwards. In this case, the particles of the medium
perpendicular to the direction that the pulse moves. This type o
is a transverse wave.
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Examples
A wave on a string
A ripple in a pond
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Why transverse waves aNot seen in fluids?
Waves traveling through a solid medium can be either transverse w
longitudinal waves. Yet waves traveling through the bulk of a fluid (
a liquid or a gas) are always longitudinal waves. Transverse waves re
relatively rigid medium in order to transmit their energy. As one
begins to move it must be able to exert a pull on its nearest neighbo
medium is not rigid as is the case with fluids, the particles will slideach other. This sliding action that is characteristic of liquids and
prevents one particle from displacing its neighbor in a di
perpendicular to the energy transport. It is for this reason tha
longitudinal waves are observed moving through the bulk of liquids
our oceans.
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Mechanical Waves
A mechanical wave is a wave that is not capable of transmitting
energy through a vacuum.
Propagates as an oscillation of matter, and therefore trans
energy through a medium.
No material is transported as a result of mechanical wa
Mechanical wave can be produced only in media which posselasticity and inertia.
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Important property of mechanical waves is that their amp
possess an unusual form, displacement divided by reduced wavel
When this gets comparable to unity, significant nonlinear effectas harmonic generation may occur, and, if large enough, may re
chaotic effects.
For example, waves on the surface of a body of water break whe
dimensionless amplitude exceeds 1, resulting in a foam on the sand turbulent mixing. Some of the most common examp
mechanical waves can be water waves, sound waves.
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ExamplesExamples of mechanical waves are transverse wave, longitudin
wave, surface wave.
Surface wave is a wave in which particles of the medium undergo
circular motion. Surface waves are neither longitudinal n
transverse. In longitudinal and transverse waves, all the particles
the entire bulk of the medium move in a parallel and
perpendicular direction (respectively) relative to the direction
energy transport. In a surface wave, it is only the particles at thsurface of the medium that undergo the circular motion. T
motion of particles tends to decrease as one proceeds furth
from the surface
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Surface wave on pool water
Surface wave on sea
currents
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Electromagnetic Wave
An electromagnetic wave consists of two waves that are
oscillations of the electric and magnetic fields.
An electromagnetic wave travels in a direction that is at right
angles to the oscillation direction of both fields.
An electromagnetic wave is a wave that is capable of transmittingits energy through a vacuum. Electromagnetic waves are
produced by the vibration of charged particles.
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Examples
Typical examples of electromagnetic waves are visible light, radio wav
microwaves, ultra-violet rays etc.
Figure showing electromagnetic propagation
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Mechanism of electromagnepropagation
The energy transport through a medium involves the absorption and reem
the wave energy by the atoms of the material.
Electromagnetic wave impinges upon the atoms of a material, the energ
wave is absorbed.
Absorption of energy causes the electrons within the atoms to undergo v
After a short period of vibrational motion, the vibrating electrons creaelectromagnetic wave with the same frequency as the first electromagnet
While these vibrations occur for only a very short time, they delay the
the wave through the medium. Once the energy of the electromagneti
reemitted by an atom, it travels through a small region of space between a
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The actual speed of an electromagnetic wave through a material med
is dependent upon the optical density of that medium.
Different materials cause a different amount of delay due to the
absorption and reemission process.
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Thank You