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Capacitance and Dielectrics
Chapter 24 Capacitance and Dielectrics PowerPoint® Lectures for University Physics, Twelfth Edition – Hugh D. Young and Roger A. Freedman Lectures by James Pazun Copyright © 2008 Pearson Education Inc., publishing as Pearson Addison-Wesley Goals for Chapter 24 • To consider capacitors and capacitance • To study the use of capacitors in series and capacitors in parallel • To determine the energy in a capacitor • To examine dielectrics and see how different dielectrics lead to differences in capacitance Copyright © 2008 Pearson Education Inc., publishing as Pearson Addison-Wesley How to Accomplish these goals: Read the chapter Study this PowerPoint Presentation Do the homework: 11, 13, 15, 39, 41, 45, 71 Copyright © 2008 Pearson Education Inc., publishing as Pearson Addison-Wesley Introduction • When flash devices made the “big switch” from bulbs and flashcubes to early designs of electronic flash devices, you could use a camera and actually hear a high-pitched whine as the “flash charged up” for your next photo opportunity. • The person in the picture must have done something worthy of a picture. Just think of all those electrons moving on camera flash capacitors! Copyright © 2008 Pearson Education Inc., publishing as Pearson Addison-Wesley Keep charges apart and you get capacitance Any two charges insulated from each other form a capacitor. When we say that a capacitor has a charge Q or that charge Q is stored in the capacitor, we mean that the conductor at higher potential has charge +Q and at lower potential has charge –Q. When the capacitor is fully charged the potential difference across it is the same as the vab that charged it. -
Electro Magnetic Fields Lecture Notes B.Tech
ELECTRO MAGNETIC FIELDS LECTURE NOTES B.TECH (II YEAR – I SEM) (2019-20) Prepared by: M.KUMARA SWAMY., Asst.Prof Department of Electrical & Electronics Engineering MALLA REDDY COLLEGE OF ENGINEERING & TECHNOLOGY (Autonomous Institution – UGC, Govt. of India) Recognized under 2(f) and 12 (B) of UGC ACT 1956 (Affiliated to JNTUH, Hyderabad, Approved by AICTE - Accredited by NBA & NAAC – ‘A’ Grade - ISO 9001:2015 Certified) Maisammaguda, Dhulapally (Post Via. Kompally), Secunderabad – 500100, Telangana State, India ELECTRO MAGNETIC FIELDS Objectives: • To introduce the concepts of electric field, magnetic field. • Applications of electric and magnetic fields in the development of the theory for power transmission lines and electrical machines. UNIT – I Electrostatics: Electrostatic Fields – Coulomb’s Law – Electric Field Intensity (EFI) – EFI due to a line and a surface charge – Work done in moving a point charge in an electrostatic field – Electric Potential – Properties of potential function – Potential gradient – Gauss’s law – Application of Gauss’s Law – Maxwell’s first law, div ( D )=ρv – Laplace’s and Poison’s equations . Electric dipole – Dipole moment – potential and EFI due to an electric dipole. UNIT – II Dielectrics & Capacitance: Behavior of conductors in an electric field – Conductors and Insulators – Electric field inside a dielectric material – polarization – Dielectric – Conductor and Dielectric – Dielectric boundary conditions – Capacitance – Capacitance of parallel plates – spherical co‐axial capacitors. Current density – conduction and Convection current densities – Ohm’s law in point form – Equation of continuity UNIT – III Magneto Statics: Static magnetic fields – Biot‐Savart’s law – Magnetic field intensity (MFI) – MFI due to a straight current carrying filament – MFI due to circular, square and solenoid current Carrying wire – Relation between magnetic flux and magnetic flux density – Maxwell’s second Equation, div(B)=0, Ampere’s Law & Applications: Ampere’s circuital law and its applications viz. -
Rigid Body Dynamics: Student Misconceptions and Their Diagnosis1
Rigid Body Dynamics: Student Misconceptions and Their Diagnosis1 D. L. Evans2, Gary L. Gray3, Francesco Costanzo4, Phillip Cornwell5, Brian Self6 Introduction: As pointed out by a rich body of research literature, including the three video case studies, Lessons from Thin Air, Private Universe, and, particularly, Can We Believe Our Eyes?, students subjected to traditional instruction in math, science and engineering often do not adequately resolve the misconceptions that they either bring to a subject or develop while studying a subject. These misconceptions, sometimes referred to as alternative views or student views of basic concepts because they make sense to the student, block the establishment of connections between basic concepts, connections which are necessary for understanding the macroconceptions that build on the basics. That is, the misconceptions of basic phenomena hinder the learning of further material that relies on understanding these concepts. The literature on misconceptions includes the field of particle mechanics, but does not include rigid body mechanics. For example, it has been established7 "that … commonsense beliefs about motion and force are incompatible with Newtonian concepts in most respects…" It is also known that replacing these "commonsense beliefs" with concepts aligned with modern thinking on science is extremely difficult to accomplish8. But a proper approach to accomplishing this replacement must begin with understanding what the misconceptions are, progress to being able to diagnose them, and eventually, reach the point whereby instructional approaches are developed for addressing them. In high school, college and university physics, research has led to the development of an assessment instrument called the Force Concept Inventory9 (FCI) that is now available for measuring the success of instruction in breaking these student misconceptions. -
Students' Depictions of Quantum Mechanics
Students’ depictions of quantum mechanics: a contemporary review and some implications for research and teaching Johan Falk January 2007 Dissertation for the degree of Licentiate of Philosophy in Physics within the specialization Physics Education Research Uppsala University, 2007 Abstract This thesis presents a comprehensive review of research into students’ depic- tions of quantum mechanics. A taxonomy to describe and compare quantum mechanics education research is presented, and this taxonomy is used to highlight the foci of prior research. A brief history of quantum mechanics education research is also presented. Research implications of the review are discussed, and several areas for future research are proposed. In particular, this thesis highlights the need for investigations into what interpretations of quantum mechanics are employed in teaching, and that classical physics – in particular the classical particle model – appears to be a common theme in students’ inappropriate depictions of quantum mechanics. Two future research projects are presented in detail: one concerning inter- pretations of quantum mechanics, the other concerning students’ depictions of the quantum mechanical wave function. This thesis also discusses teaching implications of the review. This is done both through a discussion on how Paper 1 can be used as a resource for lecturers and through a number of teaching suggestions based on a merging of the contents of the review and personal teaching experience. List of papers and conference presentations Falk, J & Linder, C. (2005). Towards a concept inventory in quantum mechanics. Presentation at the Physics Education Research Conference, Salt Lake City, Utah, August 2005. Falk, J., Linder, C., & Lippmann Kung, R. (in review, 2007). -
Experiment 1: Equipotential Lines and Electric Fields
MASSACHUSETTS INSTITUTE OF TECHNOLOGY Department of Physics 8.02 Spring 2006 Experiment 1: Equipotential Lines and Electric Fields OBJECTIVES 1. To develop an understanding of electric potential and electric fields 2. To better understand the relationship between equipotentials and electric fields 3. To become familiar with the effect of conductors on equipotentials and E fields PRE-LAB READING INTRODUCTION Thus far in class we have talked about fields, both gravitational and electric, and how we can use them to understand how objects can interact at a distance. A charge, for example, creates an electric field around it, which can then exert a force on a second charge which enters that field. In this lab we will study another way of thinking about this interaction through electric potentials. The Details: Electric Potential (Voltage) Before discussing electric potential, it is useful to recall the more intuitive concept of potential energy, in particular gravitational potential energy. This energy is associated with a mass’s position in a gravitational field (its height). The potential energy difference between being at two points is defined as the amount of work that must be done to move between them. This then sets the relationship between potential energy and force (and hence field): B G G dU ∆=UU−U=−Fs⋅d ⇒ ()in 1D F=− (1) BA∫ A dz We earlier defined fields by breaking a two particle interaction, force, into two single particle interactions, the creation of a field and the “feeling” of that field. In the same way, we can define a potential which is created by a particle (gravitational potential is created by mass, electric potential by charge) and which then gives to other particles a potential energy. -
An Introduction to Effective Field Theory
An Introduction to Effective Field Theory Thinking Effectively About Hierarchies of Scale c C.P. BURGESS i Preface It is an everyday fact of life that Nature comes to us with a variety of scales: from quarks, nuclei and atoms through planets, stars and galaxies up to the overall Universal large-scale structure. Science progresses because we can understand each of these on its own terms, and need not understand all scales at once. This is possible because of a basic fact of Nature: most of the details of small distance physics are irrelevant for the description of longer-distance phenomena. Our description of Nature’s laws use quantum field theories, which share this property that short distances mostly decouple from larger ones. E↵ective Field Theories (EFTs) are the tools developed over the years to show why it does. These tools have immense practical value: knowing which scales are important and why the rest decouple allows hierarchies of scale to be used to simplify the description of many systems. This book provides an introduction to these tools, and to emphasize their great generality illustrates them using applications from many parts of physics: relativistic and nonrelativistic; few- body and many-body. The book is broadly appropriate for an introductory graduate course, though some topics could be done in an upper-level course for advanced undergraduates. It should interest physicists interested in learning these techniques for practical purposes as well as those who enjoy the beauty of the unified picture of physics that emerges. It is to emphasize this unity that a broad selection of applications is examined, although this also means no one topic is explored in as much depth as it deserves. -
PHYSICS 360 Quantum Mechanics
PHYSICS 360 Quantum Mechanics Prof. Norbert Neumeister Department of Physics and Astronomy Purdue University Spring 2020 http://www.physics.purdue.edu/phys360 Course Format • Lectures: – Time: Monday, Wednesday 9:00 – 10:15 – Lecture Room: PHYS 331 – Instructor: Prof. N. Neumeister – Office hours: Tuesday 2:00 – 3:00 PM (or by appointment) – Office: PHYS 372 – Phone: 49-45198 – Email: [email protected] (please use subject: PHYS 360) • Grader: – Name: Guangjie Li – Office: PHYS 6A – Phone: 571-315-3392 – Email: [email protected] – Office hours: Monday: 1:30 pm – 3:30 pm, Friday: 1:00 pm – 3:00 pm Purdue University, Physics 360 1 Textbook The textbook is: Introduction to Quantum Mechanics, David J. Griffiths and Darrell F. Schroeter, 3rd edition We will follow the textbook quite closely, and you are strongly encouraged to get a copy. Additional references: • R.P. Feynman, R.b. Leighton and M. Sands: The Feynman Lectures on Physics, Vol. III • B.H. brandsen and C.J. Joachain: Introduction To Quantum Mechanics • S. Gasiorowicz: Quantum Physics • R. Shankar: Principles Of Quantum Mechanics, 2nd edition • C. Cohen-Tannoudji, B. Diu and F. Laloë: Quantum Mechanics, Vol. 1 and 2 • P.A.M. Dirac: The Principles Of Quantum Mechanics • E. Merzbacher: Quantum Mechanics • A. Messiah: Quantum Mechanics, Vol. 1 and 2 • J.J. Sakurai: Modern Quantum Mechanics Purdue University, Physics 360 2 AA fewA (randomfew recommended but but but recommended) recommended) recommended) books books booksBooks B. H. Bransden and C. J. Joachain, Quantum Mechanics, (2nd B. H. H.B. H. Bransden Bransden Bransden and andand C. C. C. J. J. -
Gravitational Potential Energy
Briefly review the concepts of potential energy and work. •Potential Energy = U = stored work in a system •Work = energy put into or taken out of system by forces •Work done by a (constant) force F : v v v v F W = F ⋅∆r =| F || ∆r | cosθ θ ∆r Gravitational Potential Energy Lift a book by hand (Fext) at constant velocity. F = mg final ext Wext = Fext h = mgh h Wgrav = -mgh Fext Define ∆U = +Wext = -Wgrav= mgh initial Note that get to define U=0, mg typically at the ground. U is for potential energy, do not confuse with “internal energy” in Thermo. Gravitational Potential Energy (cont) For conservative forces Mechanical Energy is conserved. EMech = EKin +U Gravity is a conservative force. Coulomb force is also a conservative force. Friction is not a conservative force. If only conservative forces are acting, then ∆EMech=0. ∆EKin + ∆U = 0 Electric Potential Energy Charge in a constant field ∆Uelec = change in U when moving +q from initial to final position. ∆U = U f −Ui = +Wext = −W field FExt=-qE + Final position v v ∆U = −W = −F ⋅∆r fieldv field FField=qE v ∆r → ∆U = −qE ⋅∆r E + Initial position -------------- General case What if the E-field is not constant? v v ∆U = −qE ⋅∆r f v v Integral over the path from initial (i) position to final (f) ∆U = −q∫ E ⋅dr position. i Electric Potential Energy Since Coulomb forces are conservative, it means that the change in potential energy is path independent. f v v ∆U = −q∫ E ⋅dr i Electric Potential Energy Positive charge in a constant field Electric Potential Energy Negative charge in a constant field Observations • If we need to exert a force to “push” or “pull” against the field to move the particle to the new position, then U increases. -
Teaching Light Polarization by Putting Art and Physics Together
Teaching Light Polarization by Putting Art and Physics Together Fabrizio Logiurato Basic Science Department, Ikiam Regional Amazonian University, Ecuador Physics Department, Trento University, Italy molecules. In mechanical engineering birefringence is exploited to detect stress in structures. Abstract—Light Polarization has many technological Unfortunately, light polarization is usually considered a applications and its discovery was crucial to reveal the transverse marginal concept in school programs. In order to fill this gap, nature of the electromagnetic waves. However, despite its we have developed an interdisciplinary laboratory on this fundamental and practical importance, in high school this property of subject for high school and undergraduate students. In this one light is often neglected. This is a pity not only for its conceptual relevance, but also because polarization gives the possibility to pupils have the possibility to understand the physics of light perform many beautiful experiments with low cost materials. polarization, its connections with the chemistry and the basics Moreover, the treatment of this matter lends very well to an of its applications. Beautiful and fascinating images appear interdisciplinary approach, between art, biology and technology, when we set between two crossed polarizing filters some which usually makes things more interesting to students. For these materials. The pictures that we can see are similar to those of reasons we have developed a laboratory on light polarization for high the abstract art. Students can create their own artistic school and undergraduate students. They can see beautiful pictures when birefringent materials are set between two crossed polarizing compositions, take photos of them and make their experiments filters. -
Integrated Dynamics and Statics for First Semester Sophomores in Mechanical Engineering
AC 2010-845: INTEGRATED DYNAMICS AND STATICS FOR FIRST SEMESTER SOPHOMORES IN MECHANICAL ENGINEERING Sherrill Biggers, Clemson University Sherrill B. Biggers is Professor of Mechanical Engineering at Clemson University. He has over 29 years of experience in teaching engineering mechanics, including statics, dynamics, and strength of materials at two universities. His technical research is in the computational mechanics and optimal design of advanced composite structures. He developed advanced structural mechanics design methods in the aerospace industry for over 10 years. Recently he has also contributed to research being conducted in engineering education. He received teaching awards at Clemson and the University of Kentucky. He has been active in curriculum and course development over the past 20 years. He received his BS in Civil Engineering from NC State University and his MS and Ph.D. in Civil Engineering from Duke University. Marisa Orr, Clemson University Marisa K. Orr is a doctoral candidate in the Mechanical Engineering program at Clemson University. She is a research assistant in the Department of Engineering and Science Education and is a member of the inaugural class of the Engineering and Science Education Certificate at Clemson University. As an Endowed Teaching Fellow, she received the Departmental Outstanding Teaching Assistant Award for teaching Integrated Statics and Dynamics for Mechanical Engineers. Her research involves analysis of the effects of student-centered active learning in sophomore engineering courses, and investigation of the career motivations of women and men as they relate to engineering. Lisa Benson, Clemson University Page 15.757.1 Page © American Society for Engineering Education, 2010 Integrated Dynamics and Statics for First Semester Sophomores in Mechanical Engineering Abstract A modified SCALE-UP approach that emphasizes active learning, guided inquiry, and student responsibility has been described as applied to an innovative and challenging sophomore course that integrates Dynamics and Statics. -
University Physics I COURSE SYLLABUS: Spring 2013
PHYS 2425: University Physics I COURSE SYLLABUS: Spring 2013 Instructor: Dr. Kent Montgomery Office Location: Science 148 Office Hours: MTWTh 9:00–10:00 or by appointment Office Phone: 903‐468‐8650 University Email Address: [email protected] Course Location and Time: Lectures: MWF 11:00 a.m. – 11:50 a.m., Science 123 Labs: Wednesday 1:00 p.m. – 2:50 p.m., Science 114 or Thursday 1:00 p.m. – 2:50 p.m., Science 114 Suggested Companion Course (not required): PHYS 201: Problem Solving in Mechanics, Call #21384, Tuesday 3:30 p.m. – 4:20 p.m., Science 123 COURSE INFORMATION Materials – Textbooks, Readings, Supplementary Readings: Textbooks Required: Fundamentals of Physics Extended, 9th edition, Halliday, Resnick, and Walker There are alternate versions of the text that are acceptable; contact me for details. Course Description: Physics is the study of the interactions of matter and energy. This course will cover mechanics, or the study of how objects move. We will study motion, forces, gravity, and rotation during this semester. Prerequisites: Math 191 or Math 2413 (Calculus I) or be concurrently taking Calculus I Student Learning Outcomes: 1. You will be able to describe the motion of objects in up to three dimensions in terms of their position, displacement, velocity, and acceleration. 2. You will be able to describe how forces change an object’s motion. 3. You will be able to calculate the motion of an object due to the application of one or more forces. 4. You will be able to describe and calculate various kinds of energy and use energy to calculate the motion of objects. -
PET4I101 ELECTROMAGNETICS ENGINEERING (4Th Sem ECE- ETC) Module-I (10 Hours)
PET4I101 ELECTROMAGNETICS ENGINEERING (4th Sem ECE- ETC) Module-I (10 Hours) 1. Cartesian, Cylindrical and Spherical Coordinate Systems; Scalar and Vector Fields; Line, Surface and Volume Integrals. 2. Coulomb’s Law; The Electric Field Intensity; Electric Flux Density and Electric Flux; Gauss’s Law; Divergence of Electric Flux Density: Point Form of Gauss’s Law; The Divergence Theorem; The Potential Gradient; Energy Density; Poisson’s and Laplace’s Equations. Module-II3. Ampere’s (8 Magnetic Hours) Circuital Law and its Applications; Curl of H; Stokes’ Theorem; Divergence of B; Energy Stored in the Magnetic Field. 1. The Continuity Equation; Faraday’s Law of Electromagnetic Induction; Conduction Current: Point Form of Ohm’s Law, Convection Current; The Displacement Current; 2. Maxwell’s Equations in Differential Form; Maxwell’s Equations in Integral Form; Maxwell’s Equations for Sinusoidal Variation of Fields with Time; Boundary Module-IIIConditions; (8The Hours) Retarded Potential; The Poynting Vector; Poynting Vector for Fields Varying Sinusoid ally with Time 1. Solution of the One-Dimensional Wave Equation; Solution of Wave Equation for Sinusoid ally Time-Varying Fields; Polarization of Uniform Plane Waves; Fields on the Surface of a Perfect Conductor; Reflection of a Uniform Plane Wave Incident Normally on a Perfect Conductor and at the Interface of Two Dielectric Regions; The Standing Wave Ratio; Oblique Incidence of a Plane Wave at the Boundary between Module-IVTwo Regions; (8 ObliqueHours) Incidence of a Plane Wave on a Flat Perfect Conductor and at the Boundary between Two Perfect Dielectric Regions; 1. Types of Two-Conductor Transmission Lines; Circuit Model of a Uniform Two- Conductor Transmission Line; The Uniform Ideal Transmission Line; Wave AReflectiondditional at Module a Discontinuity (Terminal in an Examination-Internal) Ideal Transmission Line; (8 MatchingHours) of Transmission Lines with Load.