This document discusses different types of electric charges:
1. Free charges, like lone protons, that can accelerate under the influence of forces. Bound charges within insulators cannot move macroscopically but can shift positions within their atoms, allowing for polarization.
2. Magnetization involves charge distributions that give rise to magnetization currents in surrounding regions.
3. Maxwell added the concept of vacuum displacement current to explain Ampere's law and charges that can exist in a vacuum.
Electromagnetic waves are an essential aspect of the study of physics, particularly in the realm of electromagnetism. These waves are characterized by their ability to propagate through space without the need for a medium, unlike mechanical waves such as sound waves. At the heart of electromagnetic theory lies the groundbreaking work of James Clerk Maxwell, who formulated a set of equations that unified the phenomena of electricity and magnetism.
Electromagnetic waves are an essential aspect of the study of physics, particularly in the realm of electromagnetism. These waves are characterized by their ability to propagate through space without the need for a medium, unlike mechanical waves such as sound waves. At the heart of electromagnetic theory lies the groundbreaking work of James Clerk Maxwell, who formulated a set of equations that unified the phenomena of electricity and magnetism.
How a free electron is generated in a semiconductor Why the number o.pdfrajeshjain2109
How a free electron is generated in a semiconductor? Why the number of free electrons and
holes are not always the same?
Solution
At low temperatures the electrons are bound in their respective positions in the crystal;
consequently, they are not available for electrical conduction. At higher temperatures thermal
vibration may break some of the covalent bonds. The breaking of a bond yields a free electron
that can participate in current conduction. Once an electron moves away from a covalent bond,
there is an electron deficiency in that bond. This deficiency may be filled by one of the
neighbouring electrons, which results in a shift of the deficiency location from one site to
another. This deficiency may thus be regarded as a particle similar to an electron. This fictitious
particle, dubbed a hole, carries a positive charge and moves, under the influence of an applied
electric field, in a direction opposite to that of an electron.
In a semiconductor the mobility of electrons (referring to ‘conduction electrons’ or ‘free-
electrons’) is greater than that of a holes (indirectly referring to ‘valence electrons’) because of
different band structure and scattering mechanisms of these two carrier types.
Conduction electrons (free-electrons) travel in the conduction band and valence electrons (holes)
travel in the valence band. In an applied electric field, valence electrons cannot move as freely as
the free electrons because their movement is restricted. The mobility of a particle in a
semiconductor is larger if its effective mass is smaller and the time between scattering events is
larger.
Holes are created by the elevation of electrons from innermost shells to higher shells or shells
with higher energy levels. Since holes are subjected to the stronger atomic force pulled by the
nucleus than the electrons residing in the higher shells or farther shells, holes have a lower
mobility..
How a free electron is generated in a semiconductor Why the number o.pdfrajeshjain2109
How a free electron is generated in a semiconductor? Why the number of free electrons and
holes are not always the same?
Solution
At low temperatures the electrons are bound in their respective positions in the crystal;
consequently, they are not available for electrical conduction. At higher temperatures thermal
vibration may break some of the covalent bonds. The breaking of a bond yields a free electron
that can participate in current conduction. Once an electron moves away from a covalent bond,
there is an electron deficiency in that bond. This deficiency may be filled by one of the
neighbouring electrons, which results in a shift of the deficiency location from one site to
another. This deficiency may thus be regarded as a particle similar to an electron. This fictitious
particle, dubbed a hole, carries a positive charge and moves, under the influence of an applied
electric field, in a direction opposite to that of an electron.
In a semiconductor the mobility of electrons (referring to ‘conduction electrons’ or ‘free-
electrons’) is greater than that of a holes (indirectly referring to ‘valence electrons’) because of
different band structure and scattering mechanisms of these two carrier types.
Conduction electrons (free-electrons) travel in the conduction band and valence electrons (holes)
travel in the valence band. In an applied electric field, valence electrons cannot move as freely as
the free electrons because their movement is restricted. The mobility of a particle in a
semiconductor is larger if its effective mass is smaller and the time between scattering events is
larger.
Holes are created by the elevation of electrons from innermost shells to higher shells or shells
with higher energy levels. Since holes are subjected to the stronger atomic force pulled by the
nucleus than the electrons residing in the higher shells or farther shells, holes have a lower
mobility..
Synthetic Fiber Construction in lab .pptxPavel ( NSTU)
Synthetic fiber production is a fascinating and complex field that blends chemistry, engineering, and environmental science. By understanding these aspects, students can gain a comprehensive view of synthetic fiber production, its impact on society and the environment, and the potential for future innovations. Synthetic fibers play a crucial role in modern society, impacting various aspects of daily life, industry, and the environment. ynthetic fibers are integral to modern life, offering a range of benefits from cost-effectiveness and versatility to innovative applications and performance characteristics. While they pose environmental challenges, ongoing research and development aim to create more sustainable and eco-friendly alternatives. Understanding the importance of synthetic fibers helps in appreciating their role in the economy, industry, and daily life, while also emphasizing the need for sustainable practices and innovation.
We all have good and bad thoughts from time to time and situation to situation. We are bombarded daily with spiraling thoughts(both negative and positive) creating all-consuming feel , making us difficult to manage with associated suffering. Good thoughts are like our Mob Signal (Positive thought) amidst noise(negative thought) in the atmosphere. Negative thoughts like noise outweigh positive thoughts. These thoughts often create unwanted confusion, trouble, stress and frustration in our mind as well as chaos in our physical world. Negative thoughts are also known as “distorted thinking”.
Unit 8 - Information and Communication Technology (Paper I).pdfThiyagu K
This slides describes the basic concepts of ICT, basics of Email, Emerging Technology and Digital Initiatives in Education. This presentations aligns with the UGC Paper I syllabus.
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.
Model Attribute Check Company Auto PropertyCeline George
In Odoo, the multi-company feature allows you to manage multiple companies within a single Odoo database instance. Each company can have its own configurations while still sharing common resources such as products, customers, and suppliers.
The French Revolution, which began in 1789, was a period of radical social and political upheaval in France. It marked the decline of absolute monarchies, the rise of secular and democratic republics, and the eventual rise of Napoleon Bonaparte. This revolutionary period is crucial in understanding the transition from feudalism to modernity in Europe.
For more information, visit-www.vavaclasses.com
2024.06.01 Introducing a competency framework for languag learning materials ...Sandy Millin
http://sandymillin.wordpress.com/iateflwebinar2024
Published classroom materials form the basis of syllabuses, drive teacher professional development, and have a potentially huge influence on learners, teachers and education systems. All teachers also create their own materials, whether a few sentences on a blackboard, a highly-structured fully-realised online course, or anything in between. Despite this, the knowledge and skills needed to create effective language learning materials are rarely part of teacher training, and are mostly learnt by trial and error.
Knowledge and skills frameworks, generally called competency frameworks, for ELT teachers, trainers and managers have existed for a few years now. However, until I created one for my MA dissertation, there wasn’t one drawing together what we need to know and do to be able to effectively produce language learning materials.
This webinar will introduce you to my framework, highlighting the key competencies I identified from my research. It will also show how anybody involved in language teaching (any language, not just English!), teacher training, managing schools or developing language learning materials can benefit from using the framework.
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.
Read| The latest issue of The Challenger is here! We are thrilled to announce that our school paper has qualified for the NATIONAL SCHOOLS PRESS CONFERENCE (NSPC) 2024. Thank you for your unwavering support and trust. Dive into the stories that made us stand out!
3. Conservation of electriccharge
Free charge
a free charge is simply a charge free to
accelerate under the influence of a force.
For example, a lone proton is a free charge.
If another lone proton were to interact
with this proton, then they both would
accelerate away from each other. This
behavior is common in conductors, as
electrons aren't bound by their parent
atoms
4. Conservation of electriccharge
an insulator harbors bound charges. These
charges can't move on a large,
macroscopic scale, but can move within
their atoms. This is how polarization can
occur; an outside electric field can exert a
force on bound electrons, which all move
to one side of their respective atom,
resulting in the said insulator having
opposite sides of opposite charge.
Bound charge
5. Conservation of electriccharge
When a body is magnetized,
there will be a vector potential in
the surrounding region which
gives rise to a current density Je
called magnetization current
density.
Charge involving
in
magnetization
currents
