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Properties and Behavior of Electromagnetic Radiation

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Electromagnetic Radiation Meaning

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EMR Meaning: In physics, electromagnetic radiation (EM radiation or EMR) alludes to the waves (or their quanta, photons) of the electromagnetic field, spreading (emanating) through space, conveying electromagnetic radiant energy.


Electromagnetic Behaviour:

Electromagnetic waves are radiated by electrically charged particles going through acceleration, and these waves can consequently interact with other charged particles, applying force on them.


Electromagnetic Properties:

EM waves convey energy, momentum, and angular momentum (precise energy) away from their source particle and can grant those quantities to matter with which they interact.

On this page, we will discuss the properties and behaviour of EMR in detail.


Electromagnetic Radiation

Electromagnetic Radiation incorporates radio waves, microwaves, infrared, (visible) light, bright, X-rays, and gamma rays. These waves structure part of the electromagnetic spectrum/range.

Now, let’s understand the science behind the electromagnetic range:

Classically, electromagnetic radiation comprises electromagnetic waves, which are synchronized oscillations/vibrations of electric and magnetic fields. 

In a vacuum, electromagnetic waves travel at the speed of light, generally meant c. In a homogeneous, isotropic media, the motions of the two fields are perpendicular to one another and to the direction of energy and wave proliferation, framing a transverse/crossover wave. 

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The wavefront of electromagnetic waves transmitted from a point source (like a light) is a sphere. 

The position of an electromagnetic wave inside the electromagnetic range can be portrayed by either its frequency of wavering/oscillations or its frequency. The electromagnetic spectrum of various frequencies is called by various names since they have various sources and impacts on the matter. Arranged by increasing frequency and decreasing wavelength, and vice-versa, these are radio waves, microwaves, infrared radiation, visible light, bright radiation, X-rays, and gamma rays.


Electromagnetic Radiation - Properties and Behaviour

In regular human experience, the impression of visible light, followed by radio waves, infrared radiation, and bright beams, are the most pertinent and ever now and again experienced bits of the electromagnetic range. The impression of higher energy X-rays, for example, gets pertinent for X-ray space telescopes and atomic weapons examination and plan. This page will manage the regular types of electromagnetic radiation with its properties and behaviour.

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Scattering Reflection and Refraction

The below image shows the scattering, reflection, and refraction of electromagnetic radiation:

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Scattering:

All electromagnetic radiation is liable to scattering/dispersing by the medium, viz: gas, fluid, or solid) through which it passes. 


The cycle where energy is taken out from a beam of electromagnetic radiation and reemitted with an adjustment in a direction, phase, or wavelength is known as the scattering of Electromagnetic radiation.


The scattering process in these wavelength regions comprises of speed increase of the electrons (acceleration of a charge) by the incident beam, trailed by reradiation from the speeding up charges. It is divided into the following types:


Scattering processes might be partitioned by the time between the absorption of energy from the incident beam, and the resulting reradiation. These are as follows:

  1. Inelastic scattering

  2. Brillouin and Rayleigh scattering

  3. Large particles (Tyndall Effect)

  4. Critical opalescence (Coherent Electromagnetic Waves)

  5. Nonlinear scattering


Do You Know?

It has been known since crafted by J. Maxwell in the nineteenth century that speeding up electric charges emanate energy and, on the other hand, that electromagnetic radiation comprises fields that speed up charged particles. 


Light in the visible, infrared, or ultraviolet region interacts essentially with the electrons in gases, fluids, and solids but not the nuclei. 


Reflection

The returning or tossing back of electromagnetic radiation by a surface whereupon the radiation is occurrence. All in all, a reflecting surface is a limit between two materials of various electromagnetic properties, like the limit among air and glass, air and water, or air and metal. 


Key Concepts: 

  1. The impression of electromagnetic radiation includes the returning or tossing back of the radiation by a surface whereupon the radiation is occurrence. 

  2. A reflecting surface is by and large the limit between two materials of various electromagnetic properties. 

  3. Devices designed/intended to reflect radiation (EMR) are called reflectors or mirrors. 

  4. The reflectivity of a surface is a proportion of the measure of reflected radiation. 

  5. Antireflection coatings are utilized to diminish the reflection from surfaces of optical hardware and devices.


Refraction

The change of course/direction of propagation of any wave marvel happens when the wave speed changes. The term is most regularly applied to visible light, yet it likewise applies to any remaining electromagnetic waves, just as to sound and water waves.


Coherent Electromagnetic Waves

As we know that light sources produce light waves of varying frequencies. For instance, an incandescent lamp covers a low transmission range (high-frequency), while a laser produces a low-range frequency. 


So, the source that produces a single and a narrow frequency is the coherent source and the property is the coherence.


The different light sources from coherent light sources interfere with each other and get combined in a space to sum and differentiate electromagnetic waves.


So, the coherence of electromagnetic waves is an ability to interfere/combine to produce interference patterns. We also call this a degree of coherence.


Fun Fact

Magnetism and Electricity were once considered discrete forces. Nonetheless, in the year 1873, Clerk Maxwell, a Scottish physicist built up a Unified Theory of electromagnetism.

FAQ (Frequently Asked Questions)

Q1: Describe the Electromagnetic Spectrum.

Ans: The electromagnetic spectrum shows the significant grouping of electromagnetic waves. The scope of frequencies and frequencies is momentous (striking). 


The division line between certain rundowns is particular, while different classes cover. Microwaves envelop the high-recurrence segment of the radio segment of the electromagnetic range. 


The part of the electromagnetic range discernible to the natural eye is known as the noticeable range. This scope of frequency is explicitly called obvious light. The scope of frequencies that the natural eye can distinguish is from 380 to 700 nanometers.

Q2: Define the Two Types of Electromagnetic Scattering Processes.

Ans:

Inelastic Scattering:

In 1928 C. V. Raman found the interaction in which light was inelastically dissipated and its energy was moved by a sum equivalent to the vibrational energy of a particle or precious stone. Such dissipating is normally called the Raman impact. 


This term has been utilized in a more broad manner, nonetheless, frequently to depict inelastic dispersing of light by turn waves in magnetic crystals, by plasma waves in semiconductors, or by such extraordinary excitations as "rotons," the rudimentary quanta of superfluid helium.


Critical opalescence is a marvel that emerges in the region of a continuous/second-order phase transition, most normally shown in parallel liquid blends, like methanol and cyclohexane. 


Initially detailed by Charles Cagniard de la Tour in 1823 in combinations of alcohol and water, its significance was perceived by Thomas Andrews in 1869 after his tests on the fluid gas progress in carbon dioxide.