...Chapter 17 Electric Potential Units of Chapter 17 • Electric Potential Energy and Potential Difference •Relation between Electric Potential and Electric Field •Equipotential Lines and surfaces •The Electron Volt, a Unit of Energy •Electric Potential Due to Point Charges •Potential Due to Electric Dipole; Dipole Moment •Capacitance, Dielectrics and Storage of Electric Energy Electrostatic Potential Energy and Potential Difference The electrostatic force is conservative – potential energy can be defined as ΔPE= -W Change in electric potential energy is negative of work done by electric force: W =Fd=qEd Electric potential is defined as potential energy per unit charge: Unit of electric potential: the volt (V). 1 V = I J/C. Only changes in potential can be measured, Electrostatic Potential Energy and relation between Electric potential and Electric field Analogy between gravitational and electrical potential energy: Work is charge multiplied by potential: Work is also force multiplied by distance: If the field is not uniform, it can be calculated at multiple points: Solving problems Example 17-2: suppose an electron in a picture tube of television set is acclerated from rest through a potential difference of Vb-Va = Vba = + 50000V. (a) What is the change in electric potential energy of the electron? (b) What is the speed of the electron as a result of this acceleration? Equipotential Lines Electric potential can be represented with diagram...
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...One of the most commonly used as electrode materials at commercial scale is Activated carbons. The aim of the research is to determine the factors that contribute to the specific capacitance i.e. capacitance (C) per mass of the electrode (m) and series resistance (diffusion resistance, ohmic resistance and mass transfer resistance) in such materials. At the same time, a correlation between pore size, pore size distribution and pore length with specific capacitance (24) have been researched. Studies at the Chinese Academy of Science have shown that activated carbon nanotubes achieve higher specific capacitance than normal carbon nanotubes (25). Apart from activated carbon, metal oxides and polymeric materials have also gained considerable interest as research suggests that higher specific capacitances compared to activated carbon can be attainable using these materials (26). Table 2.2: Different types of capacitors prepared with their capacitance MATERIALS ELECTROLYTE PROCESS USED CAPACITANCE REF. Activated Carbon 6 M KOH Microwave Heating 361 F/g (27) C2H4 + C2H3N (C2H5)4N(BF4) CVD 146 F/g...
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...Our reference: MR 10661 P-authorquery-v11 AUTHOR QUERY FORM Journal: MR Please e-mail or fax your responses and any corrections to: E-mail: corrections.esch@elsevier.sps.co.in Article Number: 10661 Fax: +31 2048 52799 Dear Author, Please check your proof carefully and mark all corrections at the appropriate place in the proof (e.g., by using on-screen annotation in the PDF file) or compile them in a separate list. Note: if you opt to annotate the file with software other than Adobe Reader then please also highlight the appropriate place in the PDF file. To ensure fast publication of your paper please return your corrections within 48 hours. For correction or revision of any artwork, please consult http://www.elsevier.com/artworkinstructions. Any queries or remarks that have arisen during the processing of your manuscript are listed below and highlighted by flags in the proof. Click on the ‘Q’ link to go to the location in the proof. Location in article Query / Remark: click on the Q link to go Please insert your reply or correction at the corresponding line in the proof Q1 Q2 Q3 Q4 Please confirm that given names and surnames have been identified correctly. Kindly check whether the affiliation ‘a’ is okay as typeset, and correct if necessary. Kindly check whether the identification of corresponding author and details are okay as typeset, and correct if necessary. Kindly check and approve the edit of this line ‘It is known that the breakdown of MIM capacitors is...’...
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...between two parallel plates and the capacitance, and the how the material of the plates impact the capacitance of the capacitor. In the first part, we are going to set vary the distance between two plates at interval of 0.5cm from 0.25cm to 4 cm to get sufficient data. In the second part of this experiment, we are going to change the material between two parallel plates in order to change the dielectric constant. Introduction: 1. We use a large parallel-plate capacitor in this experiment. It has two conductors and separated by an insulator. Because it stores capacitance, we call it capacitor. We connected one side of the capacitor with positive pole and the other side with negative pole. The amount of the charge on the capacitor is about the difference V and the magnitude of the capacitance on this capacitor: Q=CV 2. A simple parallel plate capacitor consists of two parallel conductors and is split by a distance. We also have a formula to descript the relationship between capacitance and some constants and variables. C= κεA/d Where κ is the dielectric constant, ε is the permittivity of free space (8.85*10^-12 C2/Nm2), and A is the cross sectional area of the parallel plates. Meanwhile, different sorts of material have different dielectric constant. With the increasing of distance between two plates, the capacitance is going to decrease. In addition, different material of the plates will have different capacitances. Material and Methods: 1. In...
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...Dielectric strength is the maximum voltage which the dielectric material can withstand before its breakdown. The dielectric strength of the substance is measured through the thickness or width of the dielectric material and is measured in terms of volts per meter. Dielectric Relaxation The effect on the dipole moment when the when the dielectric substance is removed form electric field after a long time application of the electric field so that the dielectric substance is fully polarized. When the dielectric substance is place in the Electric Filed the material gets polarized so that their electric field of all the dipoles will be in the same direction now if we remove the electric field then the arrangement of the molecules, their electric field direction, and the dipole moment of the molecules starts changing because of the collision and the random motion of the molecules and this disorientation occurs exponentially which depend on the properties of the material Dipolar polarization fails to follow the external electric field frequency starting for the micro wave frequencies (〖10〗^11). Ionic polarization fails to compete the external electric field frequency form far...
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...ABSTRACT: - The transmission lines are considered to be impedance matching circuits designed to deliver rf power from the transmitter to the antenna, and maximum signal from the antenna to the receiver. During this signal transfer certain types of losses occurs e.g.-conductor losses, dielectric heating losses, radiation losses, insertion losses, power losses, and losses due to corona. The objective of this paper is to discuss all these losses. INTRODUCTION:- Before discussing about losses in transmission lines we have to know about transmission lines, their history, their theory, their properties and different types of transmission lines. A TRANSMISSION LINE is a device designed to guide electrical energy from one point to another. It is used, for example, to transfer the output rf energy of a transmitter to an antenna. This energy will not travel through normal electrical wire without great losses. Although the antenna can be connected directly to the transmitter, the antenna is usually located some distance away from the transmitter. On board ship, the transmitter is located inside a radio room and its associated antenna is mounted on a mast. A transmission line is used to connect the transmitter and the antenna. The transmission line has a single purpose for both the transmitter and the antenna. This purpose is to transfer the energy output of the transmitter to the antenna with the least possible power...
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...addressed; E-Mail: chend@ipfw.edu; Tel.: +1-260-481-6356; Fax: +1-260-481-6281. Received: 18 December 2013; in revised form: 1 August 2014 / Accepted: 4 August 2014 / Published: 8 August 2014 Abstract: An innovative prototype sensor containing A36 carbon steel as a capacitor was explored to monitor early-stage corrosion. The sensor detected the changes of the surface- rather than the bulk- property and morphology of A36 during corrosion. Thus it was more sensitive than the conventional electrical resistance corrosion sensors. After being soaked in an aerated 0.2 M NaCl solution, the sensor’s normalized electrical resistance (R/R0) decreased continuously from 1.0 to 0.74 with the extent of corrosion. Meanwhile, the sensor’s normalized capacitance (C/C0) increased continuously from 1.0 to 1.46. X-ray diffraction result indicates that the iron rust on A36 had crystals of lepidocrocite and magnetite. Keywords: carbon steel; chloride; X-ray diffraction; rust; corrosion monitoring Materials 2014, 7 1. Introduction...
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...analysis is a technique that is widely used to determine wide range parameters of MOS capacitors. These parameters involve flat-band voltage, threshold voltage, substrate doping concentration and the thickness of the gate oxides. The MOS capacitance is characterized by its capacitance, Cox. It has two capacitors that are connected in series at the depletion layer. These two capacitors are depletion layer and oxide capacitors that is, Cdep and Coxrespectively. When the MOS-capacitor is supplied by AC voltage, the gap width increase and contracts with respect to the AC frequency (Huff, 2005, pg. 219). To maintain the reliability and the quality of MOS structures is a vital practice among the MOS capacitors. The C-V measurements are employed mostly to determine the details and quality of gate oxides. On the MOS capacitor, measurements are done at the absence of the drain and source. The test operations provide the process information and at the same time ensuring efficient devices. The interface charges and bulk charges are also part of the parameters that are determined. The capacitor voltage measurements are carried out using tools like the Keithley model. The Keithley model makes use of 4200-SCS apparatus. Parameters like capacitance, voltage and current are taken. Analysis of the obtained results can be done mathematically, graphically or by use of software. When software is used, a wide range of formulas are used so as to extract the basic C-V parameters. The MOS capacitor...
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...Transistor. The device physics and electrical characteristics of the GAA SiNW TFET are investigated for better performance of gate control and low power consumption for the future scaling applications. Due to the high electric filed generated under the gate bias GAA SiNW TFET has high Ion and steep subthreshold swing. It is shown for the first time that subthreshold swing S is proportional to the diameter of the SiNW TFET and decreasing the diameter will lead to a better Ion /Ioff ratio. Device design and physics detailing the impact of drain and source engineering was discussed for SiNW TFET for lower off-state leakage current and a higher Ion with a steeper subthreshold swing S. Lastly, we have also investigated the effect of using high-k dielectric material and shorter gate length for SiNW for the future device applications. I. INTRODUCTION gate modulation gives a better Subthreshold swing which is smaller than 60 mV/decade and Lower Ioff Leakage Current of 10-14 A/um.[1],[2] Apart from Tunneling Field-Effect Transistor (TFET), Si Nanowires MOSFETs have been considered as the novel channel materials for the next-generation FET-type devices due to their novel material having promising device performance and novel transport characteristics. The outstanding performance of Si NW MOSFET is already shown in terms of high Ion /Ioff ratio and good subthreshold swings.[3],[4] We would integrate the SiNW to the channel of the TFET...
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...Electrical Properties Electrical Conduction R Ohm’s law V = IR I Area, A l V where I is current (Ampere), V is voltage (Volts) and R is the resistance (Ohms or ) of the conductor Resistivity Resistivity, = RA/l ( -m), where A is the area and l is the length of the conductor. Electrical conductivity Conductivity, = 1/ = l/RA ( -m)-1 Band Theory Electrons occupy energy states in atomic orbitals When several atoms are brought close to each other in a solid these energy states split in to a series of energy states (molecular orbitals). The spacing between these states are so small that they overlap to form an energy band. Band Theory The furthest band from the nucleus is filled with valence electrons and is called the valence band. The empty band is called the conduction band. The energy of the highest filled state is called Fermi energy. There is a certain energy gap, called band gap, between valence and conduction bands. Primarily four types of band structure exist in solids. Band Theory In metals the valence band is either partially filled (Cu) or the valence and conduction bands overlap (Mg). Insulators and semiconductors have completely filled valence band and empty conduction band. It is the magnitude of band gap which separates metals, semiconductors and insulators in terms of their electrical conductivity. The band gap is relatively smaller in semiconductors while it is very large in insulators...
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...Module 9 Non conventional Machining Version 2 ME, IIT Kharagpur Lesson 39 Electro Discharge Machining Version 2 ME, IIT Kharagpur Instructional Objectives (i) (ii) (iii) (iv) (v) (vi) (vii) (viii) (ix) (x) (xi) (xii) (xiii) (xiv) (xv) (xvi) (xvii) (xviii) (xix) Identify electro-discharge machining (EDM) as a particular type of non-tradition processes Describe the basic working principle of EDM process Draw schematically the basics of EDM Describe spark initiation in EDM Describe material removal mechanism in EDM Draw the basic electrical waveform used in EDM Identify the process parameters in EDM Describe the characteristics of EDM Identify the purpose of dielectric fluid in EDM List two common dielectric fluid Analyse the required properties of EDM tool List four common tool material for EDM Develop models for material removal rate in EDM Identify the machining characteristics in EDM Analyse the effect of process variables on surface roughness Analyse taper cut and over cut in EDM Identify different modules of EDM system Draw schematic representation of different electrical generators used in EDM Analyse working principle of RC type EDM generator 1. Introduction Electro Discharge Machining (EDM) is an electro-thermal non-traditional machining process, where electrical energy is used to generate electrical spark and material removal mainly occurs due to thermal energy of the spark. EDM is mainly used to machine difficult-to-machine...
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...Nerve Cells Group Number: 2 Members: Eugene Clifford Sian Sweeney Matthew Kinsella Akin Goktas Introduction: In this report the mechanics and electrical theories of Nerve cells will be discussed. We will explore the way Nerve cells create and transmit electrical impulses and how a nerve cell membrane can be compared to a parallel plate capacitor. Topics such as Dielectrics, Capacitance and Permittivity will also be approached. In this problem we need to find the Electric Field intensity (E) within the membrane using surface charge density (σ). Find voltage (V) using E and the distance from plate to plate (d). Plot the relationship between σ and V on a graph and thus calculate Current (I) using this information and the area (A). For the purpose of this report the membrane faces will be referred to as “plate A” and “plate B”. Theory: A nerve cell membrane acts like a dielectric parallel plate capacitor, as it is water filled (dielectric material) and has two membrane faces (plate A & B). As seen in Figure 1 below. [pic] Figure 1: A dielectric parallel plate capacitor. [1] We portray charge lining up on the outer side of each face of the membrane just as on the plates of a capacitor [2]. As external forces cause the nerve cells to electrically transmit their messages, it is safe to assume that the impulses are triggered by a change in charge density, polarity, field intensity and /or other similar factors. In this problem it is a...
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...PHYSICS FORMULAS 2426 Electron = -1.602 19 × 10-19 C = 9.11 × 10-31 kg Proton = 1.602 19 × 10-19 C = 1.67 × 10-27 kg Neutron = 0 C = 1.67 × 10-27 kg 23 6.022 × 10 atoms in one atomic mass unit e is the elementary charge: 1.602 19 × 10-19 C Potential Energy, velocity of electron: PE = eV = ½ 2 mv 1V = 1J/C 1N/C = 1V/m 1J = 1 N·m = 1 C·V 1 amp = 6.21 × 1018 electrons/second = 1 Coulomb/second 1 hp = 0.756 kW 1 N = 1 T·A·m 1 Pa = 1 N/m2 Power = Joules/second = I2R = IV [watts W] Quadratic Kinetic Energy [J] − b ± b 2 − 4ac x= Equation: KE = 1 mv 2 2 2a [Natural Log: when eb = x, ln x = b ] n: 10-9 p: 10-12 m: 10-3 µ: 10-6 f: 10-15 a: 10-18 Rectangular Notation: Z = R ± jX where +j represents inductive reactance and -j represents capacitive reactance. For example, Z = 8 + j 6Ω means that a resistor of 8Ω is in series with an inductive reactance of 6Ω. Polar Notation: Z = M ∠θ, where M is the magnitude of the reactance and θ is the direction with respect to the horizontal (pure resistance) axis. For example, a resistor of 4Ω in series with a capacitor with a reactance of 3Ω would be expressed as 5 ∠-36.9° Ω. In the descriptions above, impedance is used as an example. Rectangular and Polar Notation can also be used to express amperage, voltage, and power. To convert from rectangular to polar notation: Given: X - jY (careful with the sign before the ”j”) Magnitude: Angle: Addition of Multiple Vectors: r r r r R = Ar+ B + C r Resultant = Sum of the vectors r r Rx...
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...This page intentionally left blank Physical Constants Quantity Electron charge Electron mass Permittivity of free space Permeability of free space Velocity of light Value e = (1.602 177 33 ± 0.000 000 46) × 10−19 C m = (9.109 389 7 ± 0.000 005 4) × 10−31 kg �0 = 8.854 187 817 × 10−12 F/m µ0 = 4π10−7 H/m c = 2.997 924 58 × 108 m/s Dielectric Constant (�r� ) and Loss Tangent (� �� /� � ) Material Air Alcohol, ethyl Aluminum oxide Amber Bakelite Barium titanate Carbon dioxide Ferrite (NiZn) Germanium Glass Ice Mica Neoprene Nylon Paper Plexiglas Polyethylene Polypropylene Polystyrene Porcelain (dry process) Pyranol Pyrex glass Quartz (fused) Rubber Silica or SiO2 (fused) Silicon Snow Sodium chloride Soil (dry) Steatite Styrofoam Teflon Titanium dioxide Water (distilled) Water (sea) Water (dehydrated) Wood (dry) � r �� / � 1.0005 25 8.8 2.7 4.74 1200 1.001 12.4 16 4–7 4.2 5.4 6.6 3.5 3 3.45 2.26 2.25 2.56 6 4.4 4 3.8 2.5–3 3.8 11.8 3.3 5.9 2.8 5.8 1.03 2.1 100 80 1 1.5–4 0.1 0.000 6 0.002 0.022 0.013 0.000 25 0.002 0.05 0.000 6 0.011 0.02 0.008 0.03 0.000 2 0.000 3 0.000 05 0.014 0.000 5 0.000 6 0.000 75 0.002 0.000 75 0.5 0.000 1 0.05 0.003 0.000 1 0.000 3 0.001 5 0.04 4 0 0.01 Conductivity (� ) Material Silver Copper Gold Aluminum Tungsten Zinc Brass Nickel Iron Phosphor bronze Solder Carbon steel German silver Manganin Constantan Germanium Stainless steel , S/m 6.17 × 107 4.10 × 107 3.82 × 107 1.82 × 107 1.67 × 107 1.5 × 107 1.45 × 107 1.03...
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...charges are at the corners of a square, with B and C on opposite corners. Charges A and D, on the other two corners, have equal charge, while both B and C have a charge of +1 C. What is the charge on A so that the force on B is zero? a. -1.0 C b. -0.5 C c. -0.35 C d. -0.71 C 5. Two charges, +Q and -Q, are located two meters apart and there is a point along the line that is equidistant from the two charges as indicated. Which vector best represents the direction of the electric field at that point? a. Vector EA b. Vector EB c. Vector EC d. The electric field at that point is zero. 6. Inserting a dielectric material between two charged parallel conducting plates, originally separated by air and disconnected from a battery, will produce what effect on the capacitor? a. increase charge b. increase voltage c. increase capacitance d. decrease capacitance 7. Which of the following characteristics are held in common...
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