propagation of wave

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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

propagation of wave

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