# Physics 219 Question 1 January

Size: px
Start display at page:

Transcription

1 Lecture 6-16 Physics 219 Question 1 January A (non-ideal) battery of emf 1.5 V and internal resistance 5 Ω is connected to a light bulb of resistance 50 Ω. How much power is delivered to the light bulb? a) 0.75 W b) 0.19 W c) W d) W e) W

2 Lecture 6-26 Q +Q -Q ΔQ e - Q ΔQ Capacitors A capacitor is a device that is capable of storing electric charges and thus electric potential energy. => charging Its purpose is to release them later in a controlled way. => discharging Capacitors are used in vast majority of electrical and electronic devices. Typically made of two conductors and, when charged, each holds equal and opposite charges.

3 Lecture 6-36 Capacitance Capacitor plates hold charge Q The capacitance C of a capacitor is a measure of how much charge Q it can store for a given potential difference V between the plates. Ο V (volts) [ C] The two conductors hold charge +Q and Q, respectively. Expect [ Q] [ V] Potential difference = V = = electromotive force Let C Q V Q V Capacitance is an intrinsic property of the capacitor. = = Coulomb F Volt farad

4 Lecture 6-46 Steps to calculate capacitance C 1. Put charges Q and -Q on the two plates, respectively. 2. Calculate the electric field E between the plates due to the charges Q and -Q, e.g., by using Gauss s law. 3. Calculate the potential difference V between the plates due to the electric field E. 4. Calculate the capacitance of the capacitor by dividing the charge by the potential difference, i.e., C = Q/ V.

5 Lecture 6-56 Example: (Ideal) Parallel-Plate Capacitor 1. Put charges +q and q on plates of area A and separation d. 2. Calculate E by Gauss s Law S E ds = E A= From which we obtain: E = q A 3. Calculate V by 0 q enclosed 0 ( Eq.1) Area of Gaussian surfaces = A a b V = V V = Ed ( Eq.2) b a

6 Lecture To obtain C, divide q by V and substitute for V and E from Eq.1 and Eq. 2 q q q A 0 C = = = = V Ed d q 0 A d q is indeed prop. to V C is prop. to A C is inversely prop. to d

7 Lecture 6-76 Numerical magnitudes Let s say: Area A= 1 cm², separation d=1 mm C Then 0 A = d = ( C / Nm ) 10 ( m ) 3 10 ( ) m ( / ) ( ) = C N m = F = pf This is on the order of 1pF (pico farad).

8 Lecture 6-86 Prefixes for Powers of 10 Multiple Prefix Abbreviation 3 10 milli m 6 10 micro μ 9 10 nano n pico p μf nf pf = 10 = 10 = F F F Generally the values of typical capacitors are more conveniently measured in μf, nf or pf.

9 Lecture 6-96 Physics 219 Question 2 January 30, You wish to make a parallel plate capacitor with C = 8.85 μf. If the plates are to be square and the distance between the plates is to be 0.1 mm (=10-4 m), what would the edge length have to be? a) m b) 100 m c) 10 m d) 316 m e) 3.4 m 0 = C 2 /(Nm 2 ), C = d 0 A

10 Lecture Capacitors in Parallel V is common q q = = = q V C 1 C 2 C 3 Equivalent Capacitor holds the same charge as C 1, C 2, C 3 hold together: Thus: C q= q1+ q2 + q3 eq q = = V q + q + q V

11 Lecture C eq q + q + q = C1+ C2 V = + C 3 If d = d = d the above result is consistent with our earlier parallel-plate capacitor result of C A 0 = d A

12 Lecture Capacitors in Series q i q V CV CV.. CV s common = C 1 1= 2 2= = i i Equivalent Capacitor is the capacitor which holds the same unique charge which C 1 or C 2 or C 3 hold individually, that is q1 = q2 = q3 = q q q Ceq = = and V = V1+ V2 + V3 V V1+ V2 + V3 After inverting both side of the above equation, we obtain: 1 V + 1 V + 2 V = = + + C q C C C eq Consistent with parallelplate capacitor result of C = d d 1 or d C 0A 1

13 Lecture Summary of Capacitor Combination Series: = C C C C eq Each Capacitor C i holds the same charge: q i =q k =q=q eq Voltages add up to V=V 1 +V 2 +.V i Parallel: C = C1+ C2+ C eq Voltages are same on each C i V i =V k =V eq Charges add up. qi = qeq

14 Lecture Physics 219 Question 3 January 30, Below, all capacitors are identical. Which combination has the largest equivalent capacitance? a b c d e

15 Lecture Energy of a charged capacitor How much energy is stored in a charged capacitor? Calculate the work required (usually provided by a battery) to charge a capacitor to Q Calculate incremental work W i needed to move charge Δq from negative plate to the positive plate at voltage V i. V i Δq q Δ V i = qi C qi q i ( / ) W = V Δ q = q C Δq i i i i i V Total work U is then the area under the V-Q curve. qi 1 1 Q U = Wi = Δ qi = qdq= C C 2 C Q 0 2 V i = U 2 1 QV Q CV 2 2 2C 2 = = =

16 Lecture Where is the energy stored? Energy is stored in the electric field itself. Think of the energy needed to charge the capacitor as being the energy needed to create the electric field. U Q 1 Q 1 Q ( ) 2 = = = 0 Ad 2 C 2 ( A / d) 2 A 0 0 The electric field is given by: Q E = σ = A 1 U = E 2 0Ad The energy density u in the field is given by: This is the energy density, u, of the electric field. u U U = = volume Ad = 0E Units: 3 J / m

### Physics Electricity & Op-cs Lecture 8 Chapter 24 sec Fall 2017 Semester Professor

Physics 24100 Electricity & Op-cs Lecture 8 Chapter 24 sec. 1-2 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

### Learnabout Electronics - AC Theory

Learnabout Electronics - AC Theory Facts & Formulae for AC Theory www.learnabout-electronics.org Contents AC Wave Values... 2 Capacitance... 2 Charge on a Capacitor... 2 Total Capacitance... 2 Inductance...

### General 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/

### Capacitance. A different kind of capacitor: Work must be done to charge a capacitor. Capacitors in circuits. Capacitor connected to a battery

Capacitance The ratio C = Q/V is a conductor s self capacitance Units of capacitance: Coulomb/Volt = Farad A capacitor is made of two conductors with equal but opposite charge Capacitance depends on shape

### Physics Jonathan Dowling. Physics 2102 Lecture 7 Capacitors I

Physics 2102 Jonathan Dowling Physics 2102 Lecture 7 Capacitors I Capacitors and Capacitance Capacitor: any two conductors, one with charge +, other with charge Potential DIFFERENCE etween conductors =

### CAPACITANCE Parallel-plates capacitor E + V 1 + V 2 - V 1 = + - E = A: Area of the plates. = E d V 1 - V 2. V = E d = Q =

Andres La Rosa Portland State University Lecture Notes PH212 CAPACITANCE Parallelplates capacitor 1 2 Q Q E V 1 V 2 V 2 V 1 = 2 E E is assumed to be uniform between the plates Q Q V (Battery) V 2 V 1 =

### Today 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

### Capacitors And Dielectrics

1 In this small e-book 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

### Potential from a distribution of charges = 1

Lecture 7 Potential from a distribution of charges V = 1 4 0 X Smooth distribution i q i r i V = 1 4 0 X i q i r i = 1 4 0 Z r dv Calculating the electric potential from a group of point charges is usually

### Capacitance and capacitors. Dr. Loai Afana

apacitance and capacitors apacitors apacitors are devices that store energy in an electric field. apacitors are used in many every-day applications Heart defibrillators amera flash units apacitors are

### Chapter 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

### Chapter 1 The Electric Force

Chapter 1 The Electric Force 1. Properties of the Electric Charges 1- There are two kinds of the electric charges in the nature, which are positive and negative charges. - The charges of opposite sign

### Agenda for Today. Elements of Physics II. Capacitors Parallel-plate. Charging of capacitors

Capacitors Parallel-plate Physics 132: Lecture e 7 Elements of Physics II Charging of capacitors Agenda for Today Combinations of capacitors Energy stored in a capacitor Dielectrics in capacitors Physics

### Friday 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

### Coulomb s constant k = 9x10 9 N m 2 /C 2

1 Part 2: Electric Potential 2.1: Potential (Voltage) & Potential Energy q 2 Potential Energy of Point Charges Symbol U mks units [Joules = J] q 1 r Two point charges share an electric potential energy

### Physics Lecture: 16 MON 23 FEB Capacitance I

Physics 2113 Jonathan Dowling Physics 2113 Lecture: 16 MON 23 FEB Capacitance I Capacitors and Capacitance Capacitor: any two conductors, one with charge +Q, other with charge Q Potential DIFFERENCE between

### ECE2262 Electric Circuits. Chapter 6: Capacitance and Inductance

ECE2262 Electric Circuits Chapter 6: Capacitance and Inductance Capacitors Inductors Capacitor and Inductor Combinations 1 CAPACITANCE AND INDUCTANCE Introduces two passive, energy storing devices: Capacitors

### ECE2262 Electric Circuits. Chapter 6: Capacitance and Inductance

ECE2262 Electric Circuits Chapter 6: Capacitance and Inductance Capacitors Inductors Capacitor and Inductor Combinations Op-Amp Integrator and Op-Amp Differentiator 1 CAPACITANCE AND INDUCTANCE Introduces

### University 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

### Chapter 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

### Electronics 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

### [1] (b) Fig. 1.1 shows a circuit consisting of a resistor and a capacitor of capacitance 4.5 μf. Fig. 1.1

1 (a) Define capacitance..... [1] (b) Fig. 1.1 shows a circuit consisting of a resistor and a capacitor of capacitance 4.5 μf. S 1 S 2 6.3 V 4.5 μf Fig. 1.1 Switch S 1 is closed and switch S 2 is left

### Danger High Voltage! Your friend starts to climb on this... You shout Get away! That s High Voltage!!! After you save his life, your friend asks:

Danger High Voltage! Your friend starts to climb on this... You shout Get away! That s High Voltage!!! After you save his life, your friend asks: What is Voltage anyway? Voltage... Is the energy (U, in

### Chapter 6. Answers to examination-style questions. Answers Marks Examiner s tips

(a) Taking natural logs on both sides of V = V o e t/c gives ln V = ln V o + ln (e t/cr ) As ln (e t/cr ) = t CR then ln V = ln V o t CR = a bt hence a = ln V o and b = CR (b) (i) t/s 20 240 270 300 mean.427.233.033

### Chapter 18. Circuit Elements, Independent Voltage Sources, and Capacitors

Chapter 18 Circuit Elements, Independent Voltage Sources, and Capacitors Ideal Wire _ + Ideal Battery Ideal Resistor Ideal Capacitor Series Parallel An ideal battery provides a constant potential difference

### Chapter 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

### Physics 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

### Chapter 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

### Look over. examples 1, 2, 3, 5, 6. Look over. Chapter 25 section 1-8. Chapter 19 section 5 Example 10, 11

PHYS Look over hapter 5 section -8 examples,, 3, 5, 6 PHYS Look over hapter 7 section 7-9 Examples 8, hapter 9 section 5 Example 0, Things to Know ) How to find the charge on a apacitor. ) How to find

### Physics 102: Lecture 04 Capacitors (& batteries)

Physics 102: Lecture 04 Capacitors (& batteries) Physics 102: Lecture 4, Slide 1 I wish the checkpoints were given to us on material that we learned from the previous lecture, rather than on material from

University of Rhode Island DigitalCommons@URI PHY 204: Elementary Physics II Physics Course Materials 2015 07. Capacitors I Gerhard Müller University of Rhode Island, gmuller@uri.edu Creative Commons License

### Physics 2401 Summer 2, 2008 Exam II

Physics 2401 Summer 2, 2008 Exam II e = 1.60x10-19 C, m(electron) = 9.11x10-31 kg, ε 0 = 8.845x10-12 C 2 /Nm 2, k e = 9.0x10 9 Nm 2 /C 2, m(proton) = 1.67x10-27 kg. n = nano = 10-9, µ = micro = 10-6, m

### Electric 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

### CAPACITANCE. Capacitor. Because of the effect of capacitance, an electrical circuit can store energy, even after being de-energized.

D ircuits APAITANE APAITANE Because of the effect of capacitance, an electrical circuit can store energy, even after being de-energized. EO 1.5 EO 1.6 EO 1.7 EO 1.8 EO 1.9 DESRIBE the construction of a

### Agenda for Today. Elements of Physics II. Capacitors Parallel-plate. Charging of capacitors

Capacitors Parallel-plate Physics 132: Lecture e 7 Elements of Physics II Charging of capacitors Agenda for Today Combinations of capacitors Energy stored in a capacitor Dielectrics in capacitors Physics

### Capacitance: The ability to store separated charge C=Q/V. Capacitors! Capacitor. Capacitance Practice SPH4UW 24/08/2010 Q = CV

SPH4UW Capacitors! Capacitance: The ability to store separate charge C=Q/V Charge Q on plates V = V V B = E 0 Charge 2Q on plates V = V V B =2E 0 E=E 0 B E=2E 0 B Physics 102: Lecture 4, Slie 1 Potential

### Lecture #2 Charge, Current, Energy, Voltage Power Kirchhoff s Current Law Kirchhoff s Voltage Law

EECS 42 Introduction to Electronics for Computer Science Andrew R. Neureuther Lecture #2 Charge, Current, Energy, Voltage Power Kirchhoff s Current Law Kirchhoff s Voltage Law Corrections Slide 3 and 9

### Class 6. Capacitance and Capacitors. Physics 106. Winter Press CTRL-L to view as a slide show. Class 6. Physics 106.

and in and Energy Winter 2018 Press CTRL-L 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

### The Capacitor. +q -q

The Capacitor I. INTRODUCTION A simple capacitor consists of two parallel plates separated by air or other insulation, and is useful for storing a charge. If a potential difference is placed across the

### (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

### iclicker A device has a charge q=10 nc and a potential V=100V, what s its capacitance? A: 0.1 nf B: 1nF C: 10nF D: F E: 1F

Lecture 8 iclicker A device has a charge q=10 nc and a potential V=100V, what s its capacitance? A: 0.1 nf B: 1nF C: 10nF D: 10 10 F E: 1F iclicker A device has a charge q=10 nc and a potential V=100V,

### Chapter 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

### ENERGY AND TIME CONSTANTS IN RC CIRCUITS By: Iwana Loveu Student No Lab Section: 0003 Date: February 8, 2004

ENERGY AND TIME CONSTANTS IN RC CIRCUITS By: Iwana Loveu Student No. 416 614 5543 Lab Section: 0003 Date: February 8, 2004 Abstract: Two charged conductors consisting of equal and opposite charges forms

### Capacitance 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

### CAPACITORS / ENERGY STORED BY CAPACITORS / CHARGING AND DISCHARGING

PHYSICS A2 UNIT 4 SECTION 3: CAPACITANCE CAPACITORS / ENERGY STORED BY CAPACITORS / CHARGING AND DISCHARGING # Question CAPACITORS 1 What is current? Current is the rate of flow of charge in a circuit

### Chapter 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

### Capacitors (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

### Lecture 7. Capacitors and Electric Field Energy. Last lecture review: Electrostatic potential

Lecture 7. Capacitors and Electric Field Energy Last lecture review: Electrostatic potential V r = U r q Q Iclicker question The figure shows cross sections through two equipotential surfaces. In both

### Basics of Network Theory (Part-I)

Basics of Network Theory (Part-I) 1. One coulomb charge is equal to the charge on (a) 6.24 x 10 18 electrons (b) 6.24 x 10 24 electrons (c) 6.24 x 10 18 atoms (d) none of the above 2. The correct relation

### Energy 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

### Physics 42 Exam 2 PRACTICE Name: Lab

Physics 42 Exam 2 PRACTICE Name: Lab 1 2 3 4 Conceptual Multiple Choice (2 points each) Circle the best answer. 1.Rank in order, from brightest to dimmest, the identical bulbs A to D. A. C = D > B > A

### Capacitor: 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:

### Experiment FT1: Measurement of Dielectric Constant

Experiment FT1: Measurement of Dielectric Constant Name: ID: 1. Objective: (i) To measure the dielectric constant of paper and plastic film. (ii) To examine the energy storage capacity of a practical capacitor.

### Exam 1--PHYS 202--S12

ame: Exam 1--PHYS 202--S12 Multiple Choice Identify the choice that best completes the statement or answers the question 1 Which of these statements is true about charging by induction? a it can only occur

### AC vs. DC Circuits. Constant voltage circuits. The voltage from an outlet is alternating voltage

Circuits AC vs. DC Circuits Constant voltage circuits Typically referred to as direct current or DC Computers, logic circuits, and battery operated devices are examples of DC circuits The voltage from

### AP Physics C. Electric Circuits III.C

AP Physics C Electric Circuits III.C III.C.1 Current, Resistance and Power The direction of conventional current Suppose the cross-sectional area of the conductor changes. If a conductor has no current,

### Capacitor 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

### Phys 2025, First Test. September 20, minutes Name:

Phys 05, First Test. September 0, 011 50 minutes Name: Show all work for maximum credit. Each problem is worth 10 points. Work 10 of the 11 problems. k = 9.0 x 10 9 N m / C ε 0 = 8.85 x 10-1 C / N m e

### Chapter 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

### AP Physics C Electricity & Magnetism Mid Term Review

AP Physics C Electricity & Magnetism Mid Term Review 1984 37. When lighted, a 100-watt light bulb operating on a 110-volt household circuit has a resistance closest to (A) 10-2 Ω (B) 10-1 Ω (C) 1 Ω (D)

### Chapter 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

### Electrical energy & Capacitance

Electrical energy & Capacitance PHY232 Remco Zegers zegers@nscl.msu.edu Room W109 cyclotron building http://www.nscl.msu.edu/~zegers/phy232.html work previously A force is conservative if the work done

### (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

### Figure 1: Capacitor circuit

Capacitors INTRODUCTION The basic function of a capacitor 1 is to store charge and thereby electrical energy. This energy can be retrieved at a later time for a variety of uses. Often, multiple capacitors

### shown 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 25-µF 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)

### Physics 212. Lecture 7. Conductors and Capacitance. Physics 212 Lecture 7, Slide 1

Physics 212 Lecture 7 Conductors and Capacitance Physics 212 Lecture 7, Slide 1 Conductors The Main Points Charges free to move E = 0 in a conductor Surface = Equipotential In fact, the entire conductor

### Direct 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

### PH 1120 Electricity and Magnetism Term B, 2009 STUDY GUIDE #2

PH 1120 Electricity and Magnetism Term B, 2009 STUDY GUIDE #2 In this part of the course we will study the following topics: Electric potential difference and electric potential for a uniform field Electric

### Louisiana 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),

### Electrical energy & Capacitance

Electrical energy & Capacitance PHY232 Remco Zegers zegers@nscl.msu.edu Room W109 cyclotron building http://www.nscl.msu.edu/~zegers/phy232.html work previously A force is conservative if the work done

### Chapter 16 Electrical Energy Capacitance. HW: 1, 2, 3, 5, 7, 12, 13, 17, 21, 25, 27 33, 35, 37a, 43, 45, 49, 51

Chapter 16 Electrical Energy Capacitance HW: 1, 2, 3, 5, 7, 12, 13, 17, 21, 25, 27 33, 35, 37a, 43, 45, 49, 51 Electrical Potential Reminder from physics 1: Work done by a conservative force, depends only

### Physics 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

### Introduction to AC Circuits (Capacitors and Inductors)

Introduction to AC Circuits (Capacitors and Inductors) Amin Electronics and Electrical Communications Engineering Department (EECE) Cairo University elc.n102.eng@gmail.com http://scholar.cu.edu.eg/refky/

### PHY102 Electricity Course Summary

TOPIC 1 ELECTOSTTICS PHY1 Electricity Course Summary Coulomb s Law The magnitude of the force between two point charges is directly proportional to the product of the charges and inversely proportional

### in series Devices connected in series will have the same amount of charge deposited on each capacitor. But different potential difference. That means

Electric Field Electricity Lecture Series Electric Field: Field an area where any charged object will experience an electric force Kirchoff s Laws The electric field lines around a pair of point charges

### = (series) Capacitors in series. C eq. Hence. Capacitors in parallel. Since C 1 C 2 V 1 -Q +Q -Q. Vab V 2. C 1 and C 2 are in series

Capacitors in series V ab V + V Q( + C Vab + Q C C C Hence C C eq eq + C C C (series) ) V ab +Q -Q +Q -Q C and C are in series C V V C +Q -Q C eq C eq is the single capacitance equivalent to C and C in

### Today 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

### Chapter 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

### Lecture Outline Chapter 21. Physics, 4 th Edition James S. Walker. Copyright 2010 Pearson Education, Inc.

Lecture Outline Chapter 21 Physics, 4 th Edition James S. Walker Chapter 21 Electric Current and Direct- Current Circuits Units of Chapter 21 Electric Current Resistance and Ohm s Law Energy and Power

### Chapter 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

### General Physics (PHY 2140)

General Physics (PHY 2140) Lecture 7 Electrostatics and electrodynamics Capacitance and capacitors capacitors with dielectrics Electric current current and drift speed resistance and Ohm s law http://www.physics.wayne.edu/~apetrov/phy2140/

### Capacitors. 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

### iclicker 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

### Review. Multiple Choice Identify the letter of the choice that best completes the statement or answers the question.

Review Multiple Choice Identify the letter of the choice that best completes the statement or answers the question. 1. When more devices are added to a series circuit, the total circuit resistance: a.

### C = 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

### RADIO AMATEUR EXAM GENERAL CLASS

RAE-Lessons by 4S7VJ 1 CHAPTER- 2 RADIO AMATEUR EXAM GENERAL CLASS By 4S7VJ 2.1 Sine-wave If a magnet rotates near a coil, an alternating e.m.f. (a.c.) generates in the coil. This e.m.f. gradually increase

### Potentials and Fields

Potentials and Fields Review: Definition of Potential Potential is defined as potential energy per unit charge. Since change in potential energy is work done, this means V E x dx and E x dv dx etc. The

### Electricity. Revision Notes. R.D.Pilkington

Electricity Revision Notes R.D.Pilkington DIRECT CURRENTS Introduction Current: Rate of charge flow, I = dq/dt Units: amps Potential and potential difference: work done to move unit +ve charge from point

### Chapter 28. Direct Current Circuits

Chapter 28 Direct Current Circuits Circuit Analysis Simple electric circuits may contain batteries, resistors, and capacitors in various combinations. For some circuits, analysis may consist of combining

### Objects usually are charged up through the transfer of electrons from one object to the other.

1 Part 1: Electric Force Review of Vectors Review your vectors! You should know how to convert from polar form to component form and vice versa add and subtract vectors multiply vectors by scalars Find

### Capacitance. 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) Parallel-plate capacitor connected to battery. (b) is a circuit

### Physics 1B Spring 2010: Final Version A 1 COMMENTS AND REMINDERS:

Physics 1B Spring 2010: Final Version A 1 COMMENTS AND REMINDERS: Closed book. No work needs to be shown for multiple-choice questions. 1. Four charges are at the corners of a square, with B and C on opposite

### Electric 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,

### Chapter 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

### Chapter 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

### Electric 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

### Chapter 27. Circuits

Chapter 27 Circuits 1 1. Pumping Chagres We need to establish a potential difference between the ends of a device to make charge carriers follow through the device. To generate a steady flow of charges,

### ENGR 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