General Physics II. Conducting concentric spheres Two concentric spheres of radii R and r. The potential difference between the spheres is


 Joshua Evans
 4 years ago
 Views:
Transcription
1 apacitors and Dielectrics The ideas of energy storage in Efields can be carried a step further by understanding the concept of "apacitance" onsider a sphere with a total charge, Q, and a radius, R From previous problems we know Q that the potential at the surface is, = k R Putting more charge on the sphere stores more energy, but the ratio of energy or potential to charge depends only on R, not on Q or That is, Q R = = 4π 0R k It's true for all charged objects that the ratio of potential to voltage depends only on the shape, so this ratio is defined as the capacitance Q The units of capacitance are 1 coulomb 1 Farad 1 F ommon values of capacitance are volts microfarads, µf (106 Farads) and picofarads, pf (101 Farads) onsider two conductors connected to the terminals of a battery The battery will supply an ual amount of charge, but of opposite sign, to each of the conductors The question arising at this point: what will be capacitance of the conductor system? Let us consider different conductor systems: Parallel plates Two conducting parallel plates separated by a distance d with charges +Q and Q The potential difference between the plates (from one plate to the other) is ρ s Qd a b = = Ed = d = o o The capacitance is Q = = d 0 onducting concentric spheres Two concentric spheres of radii R and r The potential difference between the spheres is Q 1 1 a b = = 4π o R r The capacitance is r Q 4 o = = π 1 1 R r oaxial able R 1
2 oaxial cable (two concentric conducting cylinders) of length L The inside conductor has a radius r with charge ρ and the inside surface of the outside conductor is R with charge  ρ λ R Q R a b = = ln = ln π o r π ol r The capacitance is Q π L o = = R ln r r R L Exercise There are electrical devices that are designed to store energy in this fashion These devices are referred to a "capacitors" To get an idea of the magnitude of the unit Farad, find how large a parallel plate capacitor must be in order to have a capacitance of one Farad Take the distance between the plates to be 01 mm apacitors in Electrical ircuits The circuit diagram of a capacitor You can "charge" a capacitor by connecting the capacitor to a battery (power supply) (Remember that in the electrostatic situation the wires (conductors) are uipotentials) ombinations of apacitors  this is necessary because capacitors with only certain values are available apacitors in parallel: The total capacitance of the circuit, that is uivalent to the capacitors is parallel (does the same job as the capacitors in parallel) + "top to top, bottom to bottom" "left to left, right to right" voltage "The voltage is the same across all capacitors in parallel" nd charge is _ conserved: = = = ; Q = Q + Q + Q 1 1 Using the definition of the capacitance: Q= = + + = + + ( ) = apacitors in Series: In this case the capacitors connected to each others "one after another"  similar to a train engine pulling its cars The total capabitance, can be obtained as follows "The charge on the capacitors that are in series is the same on each capacitor" voltage _
3 = + + ; Q = Q = Q = Q 1 1 Using the definition of the capacitance: Q1 Q Q = + + = Q = = + + Q 1 We can generalize our results for the total capacitances in the parallel and series circuits: = N Napacitor connected in parallel = Napacitor connected in series 1 N For two capacitors connected in series: + 1 = 1 Parallel and series combinations: Find the charge on each capacitor and the voltage across each capacitor Solution The uivalent capacitance of the circuit is = () Series( // 4) *6 = series(+ 4) = = µ F + 6 The total charge Q= =1*=4µ oulomb 1 v nd the charge on the µf capacitor is ual to the total charge: 4µ oulomb Potential(voltage) of this capacitor is =4/=8 olts From the conservation of energy voltages of the and 4µF capacitors are =18=4 volts Then the charge on the µf capacitor is 4*=8µ oulomb Then the charge on the µf capacitor is 4*=16µ oulomb Exercises Find the uivalent capacitance between points and 6 µf 4 µf µf µf 4 µf µf 8 µf µf
4 Find the uivalent capacitance between points and µf 6 µf µf 8 µf 4 µf µf and a 6 µf capacitor are connected in parallel and are charged by a 1 volt battery, as shown fter the capacitors are charged, the battery is then disconnected from the circuit The capacitors are then disconnected from each other and reconnected after the 6 µf capacitor is inverted Find the charge on each capacitor and the voltage across each 1 v µf 6 µf D D Energy stored in the capacitor When a capacitor is being "charged" by a battery (or power supply), work is done by the battery to move charge from one plate of the capacitor to the other plate s the capacitor is being charged, we can say that the capacitor is storing energy (What kind of energy?) Find the stored energy onsider a capacitor being charged by a battery fter a time t, the voltage across the capacitor is and an amount of charge q has accumulated (so far) on the plates of the capacitor To move an additional amount of charge dq from one plate to the other, the battery must do an amount of work dw, where dw = (dq) (Remember from before that W = a b U a U = b q( a b), or W = q is the work done moving a charge q through a voltage ) Formally: q Q q dw = du = dq = dq U dq = 0 = Q where U is the stored energy in the capacitor s a summary: U Q 1 1 = = = Q Question: Where is the energy stored? U Energy density is defined as the stored energy per unit volume: u = volume alculate the stored energy in a parallel plate capacitor of surface area and plate separation d Potential difference between the plates is 0 alculate energy density 0 Solution: apacitance of the parallel plate is: Q = = Then the energy is: d 1 0 U = 0 d In order to find energy density we divide U by volume =d; 4
5 U u = = 0 = 0E d d where E is the electric field between the plates and it can be defined as =Ed Dielectrics in capacitors careful glance at the uations of the capacitors shows that we can increase the capacitance of a capacitor by using some materials whose permittivity bigger than the permittivity of the air 0 These materials are known as the dielectric materials Dielectrics are insulators Electrons are not free to flow from one molecule to another The atoms in a dielectric can have dipole moments In a typical chunk of dielectric material these dipoles are randomly aligned Dipoles and therefore produce no net field as shown +Q Electric Field When a dielectric is placed between the plates of a capacitor with a surface charge density ρ the resulting electric field, E 0, tends to align the dipoles with s the field These results in a net charge density ρ s induced on the surfaces of the dielectric which in turns creates an induced electric field, E i, in the opposite direction to the applied field The total field inside the dielectric is reduced to, E = E0 Ei E0 The dielectric constant is defined as the ratio of the applied field to the total field, κ = E E0 1 (kappa) Substituting for E and solving for the induced field: κ = Ei = 1 E0 E0 Ei κ Note that κ=1 is a perfect insulator such as a vacuum and κ= is a perfect conductor How does the introduction of a dielectric affect the capacitance of a capacitor? We can find change in the potential: 1 1 = Ed = E0 d = 0 κ κ If the capacitance without dielectric 0 =Q/ 0, with dielectric it will be =Q/, eliminating Q, and 0 between uations we obtain = κ 0 Q The capacitance larger by a factor κ Some values  vacuum: κ = 1, glass: κ = 5 to 10, mica: κ = to 6 Find the capacitance of the capacitor shown in figure Solution Draw the circuit diagram of the capacitors These are parallel plate capacitors and their capavitance can be 0 calculated by using 0 = ; = κ0 Then: d / / κ 1 κ d/ κ d/ 5
6 0 / 0/ 0/ 1 = κ1 ; = κ ; = κ d d / d / Since and are series to the each other, the uivalent κκ 0 capacitance is: 1 = = + κ + κ d 1 is parallel to the 1 : κκ κκ κ 1 = 1+ 1 = + κ1 = + κ + κ d d d κ + κ onsider a parallel capacitor made of two large metal plates of L by L separated by distance d (<<) with a neutral dielectric slab Metal (thickness a, same area as the metal plates) The potential difference between the two plates is Find the amount of charge on the plates and energy stored in (a) and (b) L 1 Dielectric (a) Solution: x (a) We can think that two capacitor Metal Dielectric connected series with the capacitances 0 0L κ0l (b) 1 = = ; and = d a d a a The uivalent capacitance is 1 κ 0L = = 1+ a+ ( d a) κ The total charge on the plates Q= Energy stored in the capacitor is: W=Q/ (b) Equivalent circuit of the configuration is a capacitor connected in parallel to the two capacitoe in series with the capacitances: 0L( L x) 0Lx κ 1 ; ; 0Lx = = = d d a a The uivalent capacitance is = 1 + ; Q= and W=Q/ + Exercises parallel plate capacitor consists of plates of area 10 cm and a distance between the plates of 005 mm The space between the plates is filled with a dielectric of constant κ = 5 The capacitor is connected to a 6 volt battery a Find the capacitance of the capacitor with the dielectric b Find the charge on the plates of the capacitor c Find the induced charge on the surface of the dielectric d Find the energy stored in the capacitor e Find the energy density between the plates of the capacitor 6
7 Find the capacitance of the capacitor shown / / κ 1 κ d/ κ d/ 7
Look over. examples 1, 2, 3, 5, 6. Look over. Chapter 25 section 18. Chapter 19 section 5 Example 10, 11
PHYS Look over hapter 5 section 8 examples,, 3, 5, 6 PHYS Look over hapter 7 section 79 Examples 8, hapter 9 section 5 Example 0, Things to Know ) How to find the charge on a apacitor. ) How to find
More informationChapter 29. Electric Potential: Charged Conductor
hapter 29 Electric Potential: harged onductor 1 Electric Potential: harged onductor onsider two points (A and B) on the surface of the charged conductor E is always perpendicular to the displacement ds
More informationCapacitance and capacitors. Dr. Loai Afana
apacitance and capacitors apacitors apacitors are devices that store energy in an electric field. apacitors are used in many everyday applications Heart defibrillators amera flash units apacitors are
More informationCapacitance. PHY2049: Chapter 25 1
apacitance PHY049: hapter 5 1 oulomb s law Electric fields Equilibrium Gauss law What You Know: Electric Fields Electric fields for several charge configurations Point Dipole (along axes) Line Plane (nonconducting)
More informationCapacitors. Example 1
Physics 30AP Resistors and apacitors I apacitors A capacitor is a device for storing electrical charge that consists of two conducting objects placed near one another but not touching. A A typical capacitor
More informationChapter 24: Capacitance and Dielectrics
hapter 4: apacitance and Dielectrics apacitor: two conductors (separated by an insulator) usually oppositely charged a + b  ab proportional to charge = / ab (defines capacitance) units: F = / pc4: The
More informationChapter 24: Capacitance and Dielectrics. Capacitor: two conductors (separated by an insulator) usually oppositely charged. (defines capacitance)
hapter 4: apacitance and Dielectrics apacitor: two conductors (separated by an insulator) usually oppositely charged a b  ab proportional to charge / ab (defines capacitance) units: F / pc4: The parallel
More informationParallel Plate Capacitor, cont. Parallel Plate Capacitor, final. Capacitance Isolated Sphere. Capacitance Parallel Plates, cont.
Chapter 6 Capacitance and Dielectrics Capacitors! Capacitors are devices that store electric charge! Examples of where capacitors are used include:! radio receivers (tune frequency)! filters in power supplies!
More informationChapter 26. Capacitance and Dielectrics
Chapter 26 Capacitance and Dielectrics Capacitors Capacitors are devices that store electric charge Examples of where capacitors are used include: radio receivers filters in power supplies to eliminate
More informationAP Physics C  E & M. Slide 1 / 39 Slide 2 / 39. Slide 4 / 39. Slide 3 / 39. Slide 6 / 39. Slide 5 / 39. Capacitance and Dielectrics.
Slide 1 / 39 Slide 2 / 39 P Physics & M apacitance and ielectrics 20151205 www.njctl.org Slide 3 / 39 apacitors capacitor is any two conductors seperated by an insulator, such as air or another material.
More informationChapter 2: Capacitors And Dielectrics
hapter 2: apacitors And Dielectrics 2.1 apacitance and capacitors in series and parallel L.O 2.1.1 Define capacitance and use capacitance apacitor is a device that is capable of storing electric charges
More informationChapter 2: Capacitor And Dielectrics
hapter 2: apacitor And Dielectrics In this chapter, we are going to discuss the different ways that a capacitor could be arranged in a circuit and how its capacitance could be increased. Overview apacitor
More informationChapter 25. Capacitance
Chapter 25 Capacitance 1 1. Capacitors A capacitor is a twoterminal device that stores electric energy. 2 2. Capacitance The figure shows the basic elements of any capacitor two isolated conductors of
More informationChapter 26. Capacitance and Dielectrics
Chapter 26 Capacitance and Dielectrics Circuits and Circuit Elements Electric circuits are the basis for the vast majority of the devices used in society. Circuit elements can be connected with wires to
More informationChapter 26. Capacitance and Dielectrics
Chapter 26 Capacitance and Dielectrics Capacitors Capacitors are devices that store electric charge Examples of where capacitors are used include: radio receivers filters in power supplies to eliminate
More informationCapacitance and Dielectrics. Chapter 26 HW: P: 10,18,21,29,33,48, 51,53,54,68
Capacitance and Dielectrics Chapter 26 HW: P: 10,18,21,29,33,48, 51,53,54,68 Capacitors Capacitors are devices that store electric charge and energy Examples of where capacitors are used include: radio
More informationToday s agenda: Capacitors and Capacitance. You must be able to apply the equation C=Q/V.
Today s agenda: Capacitors and Capacitance. You must be able to apply the equation C=Q/V. Capacitors: parallel plate, cylindrical, spherical. You must be able to calculate the capacitance of capacitors
More informationDefinition of Capacitance
Definition of Capacitance The capacitance, C, of a capacitor is defined as the ratio of the magnitude of the charge on either conductor to the potential difference between the conductors Q C = ΔV The SI
More informationiclicker A metal ball of radius R has a charge q. Charge is changed q >  2q. How does it s capacitance changed?
1 iclicker A metal ball of radius R has a charge q. Charge is changed q >  2q. How does it s capacitance changed? q A: C>2 C0 B: C> C0 C: C> C0/2 D: C> C0 E: C>2 C0 2 iclicker A metal ball of
More informationElectricity and Magnetism. Capacitance
Electricity and Magnetism apacitance Sources of Electric Potential A potential difference can be created by moving charge from one conductor to another. The potential difference on a capacitor can produce
More informationEnergy Stored in Capacitors
Energy Stored in Capacitors U = 1 2 qv q = CV U = 1 2 CV 2 q 2 or U = 1 2 C 37 Energy Density in Capacitors (1) We define the, u, as the electric potential energy per unit volume Taking the ideal case
More informationChapter 24 Capacitance and Dielectrics
Chapter 24 Capacitance and Dielectrics 1 Capacitors and Capacitance A capacitor is a device that stores electric potential energy and electric charge. The simplest construction of a capacitor is two parallel
More informationChapter 24 Capacitance and Dielectrics
Chapter 24 Capacitance and Dielectrics Lecture by Dr. Hebin Li Goals for Chapter 24 To understand capacitors and calculate capacitance To analyze networks of capacitors To calculate the energy stored in
More informationCAPACITANCE. Capacitor. Because of the effect of capacitance, an electrical circuit can store energy, even after being deenergized.
D ircuits APAITANE APAITANE Because of the effect of capacitance, an electrical circuit can store energy, even after being deenergized. EO 1.5 EO 1.6 EO 1.7 EO 1.8 EO 1.9 DESRIBE the construction of a
More informationWhere C is proportionally constant called capacitance of the conductor.
PITNE Page #. INTROUTION capacitor can store energy in the form of potential energy in an electric field. In this chapter well discuss the capacity of conductors to hold charge and energy.. apacitance
More informationCapacitance and Dielectrics
Slide 1 / 39 Capacitance and Dielectrics 2011 by Bryan Pflueger Capacitors Slide 2 / 39 A capacitor is any two conductors seperated by an insulator, such as air or another material. Each conductor has
More informationHomework. Reading: Chap. 29, Chap. 31 and Chap. 32. Suggested exercises: 29.17, 29.19, 29.22, 29.23, 29.24, 29.26, 29.27, 29.29, 29.30, 29.31, 29.
Homework Reading: Chap. 29, Chap. 31 and Chap. 32 Suggested exercises: 29.17, 29.19, 29.22, 29.23, 29.24, 29.26, 29.27, 29.29, 29.30, 29.31, 29.32 Problems: 29.49, 29.51, 29.52, 29.57, 29.58, 29.59, 29.63,
More informationPhysics Electricity and Magnetism Lecture 06  Capacitance. Y&F Chapter 24 Sec. 16
Physics  lectricity and Magnetism Lecture 6  apacitance Y&F hapter 4 Sec.  6 Overview Definition of apacitance alculating the apacitance Parallel Plate apacitor Spherical and ylindrical apacitors apacitors
More informationCapacitors (Chapter 26)
Capacitance, C Simple capacitive circuits Parallel circuits Series circuits Combinations Electric energy Dielectrics Capacitors (Chapter 26) Capacitors What are they? A capacitor is an electric device
More informationSharpen thinking about connections among electric field, electric potential difference, potential energy
PHYS 2015  Week 6 Sharpen thinking about connections among electric field, electric potential difference, potential energy Apply the ideas to capacitance and the parallel plate capacitor For exclusive
More informationChapter 26. Capacitance and Dielectrics
Chapter 26 Capacitance and Dielectrics Capacitors Capacitors are devices that store electric charge Examples of where capacitors are used include: radio receivers filters in power supplies energystoring
More informationPhysics Electricity & Opcs Lecture 8 Chapter 24 sec Fall 2017 Semester Professor
Physics 24100 Electricity & Opcs Lecture 8 Chapter 24 sec. 12 Fall 2017 Semester Professor Kol@ck How Much Energy? V 1 V 2 Consider two conductors with electric potentials V 1 and V 2 We can always pick
More information(3.5.1) V E x, E, (3.5.2)
Lecture 3.5 Capacitors Today we shall continue our discussion of electrostatics and, in particular, the concept of electrostatic potential energy and electric potential. The main example which we have
More informationChapter 24. Capacitance and Dielectrics Lecture 1. Dr. Armen Kocharian
Chapter 24 Capacitance and Dielectrics Lecture 1 Dr. Armen Kocharian Capacitors Capacitors are devices that store electric charge Examples of where capacitors are used include: radio receivers filters
More informationCapacitor Construction
Capacitor Construction Topics covered in this presentation: Capacitor Construction 1 of 13 Introduction to Capacitors A capacitor is a device that is able to store charge and acts like a temporary, rechargeable
More informationClass 6. Capacitance and Capacitors. Physics 106. Winter Press CTRLL to view as a slide show. Class 6. Physics 106.
and in and Energy Winter 2018 Press CTRLL to view as a slide show. From last time: The field lines are related to the field as follows: What is the electric potential? How are the electric field and the
More informationPhysics 169. Luis anchordoqui. Kitt Peak National Observatory. Thursday, February 22, 18
Physics 169 Kitt Peak National Observatory Luis anchordoqui 1 4.1 Capacitors A capacitor is a system of two conductors that carries equal and opposite charges A capacitor stores charge and energy in the
More informationElectric Potential Energy Chapter 16
Electric Potential Energy Chapter 16 Electric Energy and Capacitance Sections: 1, 2, 4, 6, 7, 8, 9 The electrostatic force is a conservative force It is possible to define an electrical potential energy
More informationChapter 25. Capacitance
Chapter 25 Capacitance 25.2: Capacitance: 25.2: Capacitance: When a capacitor is charged, its plates have charges of equal magnitudes but opposite signs: q+ and q. However, we refer to the charge of a
More informationChapter 24 Capacitance and Dielectrics
Chapter 24 Capacitance and Dielectrics 1 Capacitors and Capacitance A capacitor is a device that stores electric potential energy and electric charge. The simplest construction of a capacitor is two parallel
More informationReading: Electrostatics 3. Key concepts: Capacitance, energy storage, dielectrics, energy in the Efield.
Reading: Electrostatics 3. Key concepts: Capacitance, energy storage, dielectrics, energy in the Efield. 1.! Questions about charging and discharging capacitors. When an uncharged capacitor is connected
More informationW05D1 Conductors and Insulators Capacitance & Capacitors Energy Stored in Capacitors
W05D1 Conductors and Insulators Capacitance & Capacitors Energy Stored in Capacitors W05D1 Reading Assignment Course Notes: Sections 3.3, 4.5, 5.15.4 1 Outline Conductors and Insulators Conductors as
More informationPhysics Electricity and Magnetism Lecture 06  Capacitance. Y&F Chapter 24 Sec. 16
Physics  lectricity and Magnetism Lecture 6  apacitance Y&F hapter 4 Sec.  6 Overview Definition of apacitance alculating the apacitance Parallel Plate apacitor Spherical and ylindrical apacitors apacitors
More informationClass 5 : Conductors and Capacitors
Class 5 : Conductors and Capacitors What is a conductor? Field and potential around conductors Defining and evaluating capacitance Potential energy of a capacitor Recap Gauss s Law E. d A = Q enc and ε
More informationPH 2222A Spring 2015
PH A Spring 15 Capacitance Lecture 7 Chapter 5 (Halliday/Resnick/Walker, Fundamentals of Physics 9 th edition) 1 Chapter 5 Capacitance In this chapter we will cover the following topics: Capacitance
More informationGeneral Physics  E&M (PHY 1308)  Lecture Notes. General Physics  E&M (PHY 1308) Lecture Notes
General Physics  E&M (PHY 1308) Lecture Notes Lecture 009: Using Capacitors SteveSekula, 15 February 2011 (created 14 February 2011) Discuss the energy stored in a capacitor Discuss how to use capacitors
More informationDesigning Information Devices and Systems I Fall 2018 Lecture Notes Note Introduction to Capacitive Touchscreen
EES 16A Designing Information Devices and Systems I Fall 2018 Lecture Notes Note 16 16.1 Introduction to apacitive Touchscreen We ve seen how a resistive touchscreen works by using the concept of voltage
More informationChapter 24 Capacitance, Dielectrics, Electric Energy Storage
Chapter 24 Capacitance, Dielectrics, Electric Energy Storage Units of Chapter 24 Capacitors (1, 2, & 3) Determination of Capacitance (4 & 5) Capacitors in Series and Parallel (6 & 7) Electric Energy Storage
More informationThe Basic Capacitor. Water Tower / Capacitor Analogy. "Partnering With Our Clients for Combined Success"
CAPACITOR BASICS I How s Work The Basic A capacitor is an electrical device which serves to store up electrical energy for release at a predetermined time. In its most basic form, it is comprised of three
More informationCapacitors And Dielectrics
1 In this small ebook we ll learn about capacitors and dielectrics in short and then we ll have some questions discussed along with their solutions. I ll also give you a practices test series which you
More informationPhys102 Second Major181 Zero Version Coordinator: Kunwar, S Monday, November 19, 2018 Page: 1
Coordinator: Kunwar, S Monday, November 19, 2018 Page: 1 Q1. A neutral metal ball is suspended by a vertical string. When a positively charged insulating rod is placed near the ball (without touching),
More informationshown in Fig. 4, is initially uncharged. How much energy is stored in the two capacitors after the switch S is closed for long time?
Chapter 25 Term 083 Q13. Each of the two 25µF capacitors, as shown in Fig. 3, is initially uncharged. How many Coulombs of charge pass through ammeter A after the switch S is closed for long time? A)
More information2014 F 2014 AI. 1. Why must electrostatic field at the surface of a charged conductor be normal to the surface at every point? Give reason.
2014 F 1. Why must electrostatic field at the surface of a charged conductor be normal to the surface at every point? Give reason. 2. Figure shows the field lines on a positive charge. Is the work done
More informationCan current flow in electric shock?
Can current flow in electric shock? Yes. Transient current can flow in insulating medium in the form of time varying displacement current. This was an important discovery made by Maxwell who could predict
More informationFriday July 11. Reminder Put Microphone On
Friday July 11 8:30 AM 9:0 AM Catch up Lecture 3 Slide 5 Electron projected in electric field problem Chapter 23 Problem 29 Cylindrical shell problem surrounding wire Show Faraday Ice Pail no chrage inside
More informationChapter 17 Electric Potential
Chapter 17 Electric Potential Units of Chapter 17 Electric Potential Energy and Potential Difference Relation between Electric Potential and Electric Field Equipotential Lines The Electron Volt, a Unit
More informationCapacitance. A capacitor consists of two conductors that are close but not touching. A capacitor has the ability to store electric charge.
Capacitance A capacitor consists of two conductors that are close but not touching. A capacitor has the ability to store electric charge. a) Parallelplate capacitor connected to battery. (b) is a circuit
More informationPhysics 142 Electrostatics 3 Page 1. Electrostatics 3. Get your facts first; then you can distort them as you please. Mark Twain
Physics 142 Electrostatics 3 Page 1 Electrostatics 3 Get your facts first; then you can distort them as you please. Mark Twain The Efield has energy stored in it that can be useful Like other forms of
More informationExam 2 Practice Problems Part 1
MASSACHUSETTS INSTITUTE OF TECHNOLOGY Department of Physics Exam 2 Practice Problems Part 1 Problem 1 Electric Field and Charge Distributions from Electric Potential An electric potential V ( z ) is described
More informationCOLLEGE PHYSICS Chapter 19 ELECTRIC POTENTIAL AND ELECTRIC FIELD
COLLEGE PHYSICS Chapter 19 ELECTRIC POTENTIAL AND ELECTRIC FIELD Electric Potential Energy and Electric Potential Difference It takes work to move a charge against an electric field. Just as with gravity,
More informationCAPACITORS / CAPACITANCE ECET11
APAITORS / APAITANE  apacitance  apacitor types  apacitors in series & parallel  R ircuit harging phase  R ircuit Discharging phase  R ircuit Steady State model  Source onversions  Superposition
More informationI. Conductors and Insulators :
Chapter 6 : Conductors  Insulators  Capacitors We have, till now, studied the electric charges and the interactions between them but not evoked how the electricity can be transfered? which meterials
More informationECE 3318 Applied Electricity and Magnetism. Spring Prof. David R. Jackson Dept. of ECE. Notes 25 Capacitance
EE 3318 pplied Electricity and Magnetism Spring 218 Prof. David R. Jackson Dept. of EE Notes 25 apacitance 1 apacitance apacitor [F] + V  +Q ++++++++++++++++++                  Q ε r
More informationElectronics Capacitors
Electronics Capacitors Wilfrid Laurier University October 9, 2015 Capacitor an electronic device which consists of two conductive plates separated by an insulator Capacitor an electronic device which consists
More informationChapter 6 Objectives
hapter 6 Engr8 ircuit Analysis Dr urtis Nelson hapter 6 Objectives Understand relationships between voltage, current, power, and energy in inductors and capacitors; Know that current must be continuous
More information1. zero. Where an electric field line crosses an equipotential surface, the angle between the field line and the equipotential is
Week 5 Where an electric field line crosses an equipotential surface, the angle between the field line and the equipotential is 1. zero 2. between zero and 90 3. 90 4. not enough information given to
More informationFREE Download Study Package from website: &
EXERISE * MARK IS MORE THAN ONE ORRET QUESTIONS. SETION A : DEFINITION OF APAIT ITANE A. A. When 0µ charge is given to an isolated conductor of capacitance 5µF. Find out following (i) Potential of the
More informationCAPACITANCE. Figure 1(a). Figure 1(b).
Reading 11 Ron Bertrand VK2DQ http://www.radioelectronicschool.com CAPACITANCE In this reading we are going to talk about capacitance. I have to make a distinction here between capacitor and capacitance.
More informationC = V Q. To find the capacitance of two conductors:
Capacitance Capacitance is a measure of the ability of two conductors to store charge when a given potential difference is established between them. Two conductors, on one of which is charge +Q and on
More informationChapter 24: Capacitance and Dielectrics
Chapter 24: Capacitance and Dielectrics When you compress/stretch a spring, we are storing potential energy This is the mechanical method to store energy It is also possible to store electric energy as
More informationToday in Physics 122: capacitors
Today in Physics 122: capacitors Parallelplate and cylindrical capacitors: calculation of capacitance as a review in the calculation of field and potential Dielectrics in capacitors Capacitors, dielectrics
More informationPhysics (
Exercises Question 2: Two charges 5 0 8 C and 3 0 8 C are located 6 cm apart At what point(s) on the line joining the two charges is the electric potential zero? Take the potential at infinity to be zero
More informationPhysics 2B Notes  Capacitors Spring 2018
Definition of a Capacitor Special Case: Parallel Plate Capacitor Capacitors in Series or Parallel Capacitor Network Definition of a Capacitor Webassign Chapter 0: 8, 9, 3, 4, 5 A capacitor is a device
More informationLecture 20. March 22/24 th, Capacitance (Part I) Chapter , Pages
Lecture 0 March /4 th, 005 Capacitance (Part I) Reading: Boylestad s Circuit Analysis, 3 rd Canadian Edition Chapter 10.16, Pages 894 Assignment: Assignment #10 Due: March 31 st, 005 Preamble: Capacitance
More informationGeneral Physics (PHY 2140)
General Physics (PHY 2140) Lecture 5 Electrostatics Electrical energy potential difference and electric potential potential energy of charged conductors Capacitance and capacitors http://www.physics.wayne.edu/~apetrov/phy2140/
More informationLouisiana State University Physics 2102, Exam 2, March 5th, 2009.
PRINT Your Name: Instructor: Louisiana State University Physics 2102, Exam 2, March 5th, 2009. Please be sure to PRINT your name and class instructor above. The test consists of 4 questions (multiple choice),
More informationHollow Conductors. A point charge +Q is placed at the center of the conductors. The induced charges are: 1. Q(I1) = Q(I2) = Q; Q(O1) = Q(O2)= +Q
O2 I2 O1 I1 Hollow Conductors A point charge +Q is placed at the center of the conductors. The induced charges are: 1. Q(I1) = Q(I2) = Q; Q(O1) = Q(O2)= +Q 2. Q(I1) = Q(I2) = +Q; Q(O1) = Q(O2)= Q 3.
More informationUniversity Physics (PHY 2326)
Chapter 23 University Physics (PHY 2326) Lecture 5 Electrostatics Electrical energy potential difference and electric potential potential energy of charged conductors Capacitance and capacitors 3/26/2015
More informationElectric Potential Energy Conservative Force
Electric Potential Energy Conservative Force Conservative force or field is a force field in which the total mechanical energy of an isolated system is conserved. Examples, Gravitation, Electrostatic,
More informationChapter 14 CAPACITORS IN AC AND DC CIRCUITS
hapter 14apacitors hapter 14 APAITORS IN A AND D IRUITS So far, all we have discussed have been electrical elements in which the voltage across the element is proportional to the current through the
More informationChapter 24: Capacitance and Dielectrics
Chapter 24: Capacitance and Dielectrics When you compress/stretch a spring, we are storing potential energy This is the mechanical method to store energy It is also possible to store electric energy as
More informationChapter 16. Electric Energy and Capacitance
Chapter 16 Electric Energy and Capacitance Electric Potential Energy The electrostatic force is a conservative force It is possible to define an electrical potential energy function with this force Work
More informationEnergy stored in a capacitor W = \ q V. i q1. Energy density in electric field i. Equivalent capacitance of capacitors in series
The Language of Physics Cwcihor Two conductors of any size or shape carrying equal and opposite charges are called a capacitor. The charge on the capacitor is directly proportional to the potential difference
More informationPhysics 1202: Lecture 4 Today s Agenda. Today s Topic :
Physics 1202: Lecture 4 Today s Agenda Announcements: Lectures posted on: www.phys.uconn.edu/~rcote/ HW assignments, solutions etc. Homework #1: On Masterphysics: due this coming Friday Go to the syllabus
More informationChapter 19 Electric Potential and Electric Field
Chapter 19 Electric Potential and Electric Field The electrostatic force is a conservative force. Therefore, it is possible to define an electrical potential energy function with this force. Work done
More informationwhich checks. capacitance is determined entirely by the dimensions of the cylinders.
4.3. IDENTIFY and SET UP: It is a parallelplate air capacitor, so we can apply the equations of Section 4.. EXEUTE: (a) (b) = ε 0 A d (c) V ab so Q V = so 0 ab V ab 6 Q 0. 48 0 = = = 604 V. 45 0 F 3 d
More informationElectrostatics and Electric Potential  Outline
Electrostatics and Electric Potential  Outline 1. Understand the basic properties of electric charge, including conservation of charge and that charges are quantized. 2. Differentiate between conductors
More informationENGR 2405 Chapter 6. Capacitors And Inductors
ENGR 2405 Chapter 6 Capacitors And Inductors Overview This chapter will introduce two new linear circuit elements: The capacitor The inductor Unlike resistors, these elements do not dissipate energy They
More information(21/703) At what distance from a point charge of 8µC would the potential equal 3.6X10 4 V?
(/73) At what distance from a point charge of 8µC would the potential equal 3.6X 4 V? (6/73) A positron has the same charge as a proton but the same mass as an electron. Suppose a positron moves 5. cm
More informationDirect Current (DC) Circuits
Direct Current (DC) Circuits NOTE: There are short answer analysis questions in the Participation section the informal lab report. emember to include these answers in your lab notebook as they will be
More informationPhysics 212. Lecture 8. Today's Concept: Capacitors. Capacitors in a circuits, Dielectrics, Energy in capacitors. Physics 212 Lecture 8, Slide 1
Physics 212 Lecture 8 Today's oncept: apacitors apacitors in a circuits, Dielectrics, Energy in capacitors Physics 212 Lecture 8, Slide 1 Simple apacitor ircuit Q +Q Q Q= Q Battery has moved charge Q
More informationChapter Electrostatic Potential and Capacitance
Chapter Electrostatic Potential and Capacitance C/ 2 C/2 Ans: Q6. MockTime.com Q1. A 4µF conductor is charged to 400 volts and then its plates are joined through a resistance of 1 kω. The heat produced
More informationElectric Potential. Capacitors (Chapters 28, 29)
Electric Potential. Capacitors (Chapters 28, 29) Electric potential energy, U Electric potential energy in a constant field Conservation of energy Electric potential, V Relation to the electric field strength
More informationA B C D E. 1 Two charges +Q and 3Q are placed in opposite corners of a square. The work required to move a test charge q from point A to point B is:
Slide 1 / 40 1 Two charges +Q and 3Q are placed in opposite corners of a square. The work required to move a test charge q from point to point is: dependent on the path taken from to directly proportional
More informationElectric Field of a uniformly Charged Thin Spherical Shell
Electric Field of a uniformly Charged Thin Spherical Shell The calculation of the field outside the shell is identical to that of a point charge. The electric field inside the shell is zero. What are the
More informationTEST 2 3 FIG. 1. a) Find expression for a capacitance of the device in terms of the area A and d, k 1 and k 2 and k 3.
TEST Giving or receiving aid in any examination is cause for dismissal from the university. Perform the necessary calculation in the spaces provided. If additional space is required, use the backs of the
More informationCapacitors are devices which can store electric charge. They have many applications in electronic circuits. They include:
CAPACITORS Capacitors are devices which can store electric charge They have many applications in electronic circuits They include: forming timing elements, waveform shaping, limiting current in AC circuits
More informationCapacitor: any two conductors, one with charge +Q, other with charge Q Potential DIFFERENCE between conductors = V
Physics 2102 Gabriela González Capacitor: any two conductors, one with charge +Q, other with charge Q Potential DIFFERENCE between conductors = V Units of capacitance: Farad (F) = Coulomb/Volt Q +Q Uses:
More informationChapter 17. Potential and Capacitance
Chapter 17 Potential and Capacitance Potential Voltage (potential) is the analogue of water pressure while current is the analogue of flow of water in say gal/min or Kg/s Think of a potential as the words
More informationSources of Potential (EMF)
Sources of Potential (EMF) A source of potential difference is sometimes called a source of EMF, a widely used term, which stands for ElectroMotive Force. Your author points out that this is an outdated
More information