Electromagnetism

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Electromagnetism Electric Charge Two types: positive and negative Like charges repel, opposites attract Forces come in a matched pair Each charge pushes or pulls on the other Forces have equal magnitudes and opposite directions Forces increase with decreasing separation Charge is quantized Charge is an intrinsic property of matter Electrons are negatively charged (-1.6 x 10-19 coulomb’s each) Protons are positively charged (+1.6 x 10-19 coulomb’s each) Net charge is the sum of an object’s charges Most objects have zero net charge (neutral – equal numbers of + and -) Electric Fields Charges push on each other through empty space Charge one creates an “electric field” This electric field pushes on charge two An electric field is a structure in space that pushes on electric charge The magnitude of the field is proportional to the magnitude of the force on a test charge The direction of the field is the direction of the force on a positive test charge Magnetic Poles Two Types: north and south Like poles repel, opposites attract Forces come in matched pairs Forces increase with decreasing separation Analogous to electric charges EXCEPT: No isolated magnetic poles have ever been found! Net pole on an object is always zero! Most atoms are magnetic, but most materials are not Atomic magnetism is perfectly cancelled Material is indifferent to nearby magnetic poles Some materials do not have full cancellation Ferromagnetic materials respond to magnetic poles Magnetic Fields A magnetic field is a structure in space that pushes on magnetic poles The magnitude of the field is proportional to the magnitude of the force on a test pole The direction of the field is in the direction of the force on a north test pole Electromagnetism (part 1) Magnetic fields Push only on magnetic poles Are produced by magnetic poles Can also be produced by changing electricity! Electric fields Push only on electric charges Are produced by electric charges Can also be produced by changing magnetism Electromagnetism (part 2) Magnetism created by Poles (but isolated poles don’t seem to exist Moving electric charges Changing electric fields Electricity created by Charges Moving magnetic poles Changing magnetic fields .

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On the Nature of Electric Charge
Vol. 9(4), pp. 54-60, 28 February, 2014 DOI: 10.5897/IJPS2013.4091 ISSN 1992 - 1950 International Journal of Physical Copyright © 2014 Author(s) retain the copyright of this article Sciences http://www.academicjournals.org/IJPS Full Length Research Paper On the nature of electric charge Jafari Najafi, Mahdi 1730 N Lynn ST apt A35, Arlington, VA 22209 USA. Received 10 December, 2013; Accepted 14 February, 2014 A few hundred years have passed since the discovery of electricity and electromagnetic fields, formulating them as Maxwell's equations, but the nature of an electric charge remains unknown. Why do particles with the same charge repel and opposing charges attract? Is the electric charge a primary intrinsic property of a particle? These questions cannot be answered until the nature of the electric charge is identified. The present study provides an explicit description of the gravitational constant G and the origin of electric charge will be inferred using generalized dimensional analysis. Key words: Electric charge, gravitational constant, dimensional analysis, particle mass change. INTRODUCTION The universe is composed of three basic elements; parameters. This approach is of great generality and mass-energy (M), length (L), and time (T). Intrinsic mathematical simplicity that simply and directly properties are assigned to particles, including mass, postulates a hypothesis for the nature of the electric electric charge, and spin, and their effects are applied in charge. Although the final formula is a guesswork based the form of physical formulas that explicitly address on dimensional analysis of electric charges, it shows the physical phenomena. The meaning of some particle existence of consistency between the final formula and properties remains opaque.
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Modeling Optical Metamaterials with Strong Spatial Dispersion
Fakultät für Physik Institut für theoretische Festkörperphysik Modeling Optical Metamaterials with Strong Spatial Dispersion M. Sc. Karim Mnasri von der KIT-Fakultät für Physik des Karlsruher Instituts für Technologie (KIT) genehmigte Dissertation zur Erlangung des akademischen Grades eines DOKTORS DER NATURWISSENSCHAFTEN (Dr. rer. nat.) Tag der mündlichen Prüfung: 29. November 2019 Referent: Prof. Dr. Carsten Rockstuhl (Institut für theoretische Festkörperphysik) Korreferent: Prof. Dr. Michael Plum (Institut für Analysis) KIT – Die Forschungsuniversität in der Helmholtz-Gemeinschaft Erklärung zur Selbstständigkeit Ich versichere, dass ich diese Arbeit selbstständig verfasst habe und keine anderen als die angegebenen Quellen und Hilfsmittel benutzt habe, die wörtlich oder inhaltlich über- nommenen Stellen als solche kenntlich gemacht und die Satzung des KIT zur Sicherung guter wissenschaftlicher Praxis in der gültigen Fassung vom 24. Mai 2018 beachtet habe. Karlsruhe, den 21. Oktober 2019, Karim Mnasri Als Prüfungsexemplar genehmigt von Karlsruhe, den 28. Oktober 2019, Prof. Dr. Carsten Rockstuhl iv To Ouiem and Adam Thesis abstract Optical metamaterials are artificial media made from subwavelength inclusions with un- conventional properties at optical frequencies. While a response to the magnetic field of light in natural material is absent, metamaterials prompt to lift this limitation and to exhibit a response to both electric and magnetic fields at optical frequencies. Due tothe interplay of both the actual shape of the inclusions and the material from which they are made, but also from the specific details of their arrangement, the response canbe driven to one or multiple resonances within a desired frequency band. With such a high number of degrees of freedom, tedious trial-and-error simulations and costly experimen- tal essays are inefficient when considering optical metamaterials in the design of specific applications.
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F = BIL (F=Force, B=Magnetic Field, I=Current, L=Length of Conductor)
Magnetism Joanna Radov Vocab: -Armature- is the power producing part of a motor -Domain- is a region in which the magnetic field of atoms are grouped together and aligned -Electric Motor- converts electrical energy into mechanical energy -Electromagnet- is a type of magnet whose magnetic field is produced by an electric current -First Right-Hand Rule (delete) -Fixed Magnet- is an object made from a magnetic material and creates a persistent magnetic field -Galvanometer- type of ammeter- detects and measures electric current -Magnetic Field- is a field of force produced by moving electric charges, by electric fields that vary in time, and by the 'intrinsic' magnetic field of elementary particles associated with the spin of the particle. -Magnetic Flux- is a measure of the amount of magnetic B field passing through a given surface -Polarized- when a magnet is permanently charged -Second Hand-Right Rule- (delete) -Solenoid- is a coil wound into a tightly packed helix -Third Right-Hand Rule- (delete) Major Points: -Similar magnetic poles repel each other, whereas opposite poles attract each other -Magnets exert a force on current-carrying wires -An electric charge produces an electric field in the region of space around the charge and that this field exerts a force on other electric charges placed in the field -The source of a magnetic field is moving charge, and the effect of a magnetic field is to exert a force on other moving charge placed in the field -The magnetic field is a vector quantity -We denote the magnetic field by the symbol B and represent it graphically by field lines -These lines are drawn ⊥ to their entry and exit points -They travel from N to S -If a stationary test charge is placed in a magnetic field, then the charge experiences no force.
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Electric Charge
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Physics 115 Lightning Gauss's Law Electrical Potential Energy Electric
Physics 115 General Physics II Session 18 Lightning Gauss’s Law Electrical potential energy Electric potential V • R. J. Wilkes • Email: [email protected] • Home page: http://courses.washington.edu/phy115a/ 5/1/14 1 Lecture Schedule (up to exam 2) Today 5/1/14 Physics 115 2 Example: Electron Moving in a Perpendicular Electric Field ...similar to prob. 19-101 in textbook 6 • Electron has v0 = 1.00x10 m/s i • Enters uniform electric field E = 2000 N/C (down) (a) Compare the electric and gravitational forces on the electron. (b) By how much is the electron deflected after travelling 1.0 cm in the x direction? y x F eE e = 1 2 Δy = ayt , ay = Fnet / m = (eE ↑+mg ↓) / m ≈ eE / m Fg mg 2 −19 ! $2 (1.60×10 C)(2000 N/C) 1 ! eE $ 2 Δx eE Δx = −31 Δy = # &t , v >> v → t ≈ → Δy = # & (9.11×10 kg)(9.8 N/kg) x y 2" m % vx 2m" vx % 13 = 3.6×10 2 (1.60×10−19 C)(2000 N/C)! (0.01 m) $ = −31 # 6 & (Math typos corrected) 2(9.11×10 kg) "(1.0×10 m/s)% 5/1/14 Physics 115 = 0.018 m =1.8 cm (upward) 3 Big Static Charges: About Lightning • Lightning = huge electric discharge • Clouds get charged through friction – Clouds rub against mountains – Raindrops/ice particles carry charge • Discharge may carry 100,000 amperes – What’s an ampere ? Definition soon… • 1 kilometer long arc means 3 billion volts! – What’s a volt ? Definition soon… – High voltage breaks down air’s resistance – What’s resistance? Definition soon..
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Glossary Module 1 Electric Charge
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Electric Charge
Chapter 2 Coulomb’s Law 2.1 Electric Charge........................................................................................................ 2 2.2 Coulomb's Law ....................................................................................................... 2 Animation 2.1: Van de Graaff Generator.................................................................. 3 2.3 Principle of Superposition....................................................................................... 4 Example 2.1: Three Charges....................................................................................... 4 2.4 Electric Field........................................................................................................... 6 Animation 2.2: Electric Field of Point Charges ........................................................ 7 2.5 Electric Field Lines................................................................................................. 8 2.6 Force on a Charged Particle in an Electric Field .................................................... 9 2.7 Electric Dipole ...................................................................................................... 10 2.7.1 The Electric Field of a Dipole......................................................................... 11 Animation 2.3: Electric Dipole................................................................................ 12 2.8 Dipole in Electric Field......................................................................................... 12 2.8.1
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FOSS Electronics Course Glossary FOSS Electronics
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Intro to Electricity by Chris Woodford Updated: May 30, 2014
Intro to Electricity By Chris Woodford Updated: May 30, 2014 Name ____________________________ Date _____________ Non-fiction Reading with questions Electricity If you've ever sat watching a thunderstorm, with mighty lightning bolts darting down from the sky, you'll have some idea of the power of electricity. A bolt of lightning is a sudden, massive surge of electricity between the sky and the ground beneath. The energy in a single lightning bolt is enough to light 100 powerful lamps for a whole day or to make a couple of hundred thousand slices of toast! Electricity is the most versatile energy source that we have; it is also one of the newest: homes and businesses have been using it for not much more than a hundred years. Electricity has played a vital part of our past. But it could play a different role in our future, with many more buildings generating their own renewable electric power using solar cells and wind turbines. Let's take a closer look at electricity and find out how it works! What is electricity? Electricity is a type of energy that can build up in one place or flow from one place to another. When electricity gathers in one place it is known as static electricity (the word static means something that does not move); electricity that moves from one place to another is called current electricity. Static electricity Static electricity often happens when you rub things together. TRY THIS: Rub a balloon against your clothing 20 or 30 times, you'll find the balloon sticks to you and maybe even the wall.
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Experiment 1: Coulomb's
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Electric Charge How Does an Object Get a Charge (Must Gain Or Lose Something)?
Topic 1: Electric Charge How does an object get a charge (must gain or lose something)? What does it mean when an object is positively charged? What about negatively charged? An object gets a charge when it is rubbed. This rubbing causes the objects to gain or lose electrons. When it loses electrons it becomes positively charged. When an object gains electrons it becomes negatively charged. What is an object called when it has an even number of positive and negative charges? It’s called balanced or NEUTRAL What are the THREE LAWS OF CHARGES? (page 268) 1. Unlike charges attract 2. Like charges repel 3. Charged objects attract uncharged objects. Define STATIC ELECTRICITY: The unbalance of electrons created by rubbing or friction in which electrons do not move. Define INSULATOR and provide an example: Doesn’t allow electrons to move through it easily. Define CONDUCTOR and provide an example: Allows electrons to move through it easily. Define SEMICONDUCTOR and provide an example: Materials with higher conductivity than insulators but lower conductivity than conductors. Define SUPERCONDUCTOR and provide an example: Materials that offer little resistance to no resistance to flow of charges. See page 269 bottom paragraph. Define GROUNDING: Connecting an object to Earth with a conducting wire. This neutralizes the charges. Describe NEUTRALIZATION: Becoming balanced. Topic 2: Electricity Within a Circuit Define CIRCUIT: A continuous pathway for charges to move along. All circuit diagrams have four basic parts. Name them, and describe what they do. 1. Source: Battery, cell etc 2. Control: Switch that can allow the electrons to follow or not on a complete path 3.
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What Is Electricity
ELECTRICITY - A Secondary Energy Source A Secondary Source The Science of Electricity How Electricity is Generated/Made The Transformer - Moving Electricity Measuring Electricity energy calculator links page recent statistics A SECONDARY SOURCE Electricity is the flow of electrical power or charge. It is a secondary energy source which means that we get it from the conversion of other sources of energy, like coal, natural gas, oil, nuclear power and other natural sources, which are called primary sources. The energy sources we use to make electricity can be renewable or non-renewable, but electricity itself is neither renewable or non-renewable. Electricity is a basic part of nature and it is one of our most widely used forms of energy. Many cities and towns were built alongside waterfalls (a primary source of mechanical energy) that turned water wheels to perform work. Before electricity generation began over 100 years ago, houses were lit with kerosene lamps, food was cooled in iceboxes, and rooms were warmed by wood-burning or coal-burning stoves. Beginning with Benjamin Franklin's experiment with a kite one stormy night in Philadelphia, the principles of electricity gradually became understood. Thomas Edison helped change everyone's life -- he perfected his invention -- the electric light bulb. Prior to 1879, direct current (DC) electricity had been used in arc lights for outdoor lighting. In the late-1800s, Nikola Tesla pioneered the generation, transmission, and use of alternating current (AC) electricity, which can be transmitted over much greater distances than direct current. Tesla's inventions used electricity to bring indoor lighting to our homes and to power industrial machines.
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