Intermediate Physics PHYS102
|
|
|
- Dwight Nelson Adams
- 5 years ago
- Views:
Transcription
1 Intermediate Physics PHYS102
2 Dr Richard H. Cyburt Assistant Professor of Physics My office: 402c in the Science Building My phone: (304) My My webpage: In person or is the best way to get a hold of me. PHYS102
3 My Office Hours TWR 9:30-11:00am W 4:00-5:00pm Meetings may also be arranged at other times, by appointment PHYS102
4 Key Dates for Lab Mon, Jan 16, 2017: No Lab, because the following Monday is MLK Jr Day. Mon, Feb 13, 2017: Lab Make Up Day Mon, Mar 20, 2017: Lab Make Up Day Mon, Apr 24, 2017: Lab Make Up Day PHYS102
5 Midterm 1 Midterm 1: Thur. Feb 2 8-9:15am Review Session: Wed. Feb 1 7-9pm in S300 PHYS102
6 Intermediate Physics PHYS102
7 Douglas Adams Hitchhiker s Guide to the Galaxy PHYS102
8 In class!! PHYS102
9 This lecture will help you understand: Capacitance and Capacitors Energy and Capacitors Model of Current PHYS102
10 Section 21.7 Capacitance and Capacitors
11 Capacitance and Capacitors A capacitor is formed by two conductors with equal but opposite charge. The two conductors are the electrodes or plates. Capacitors can be used to store charge, making them invaluable in all kinds of electronic circuits. In a capacitor, the electric field strength E and the potential difference ΔV C increase as the charge on each electrode increases.
12 Capacitance and Capacitors
13 Capacitance and Capacitors The potential difference between the electrodes is directly proportional to their charge. Stated another way, the charge of a capacitor is directly proportional to the potential difference between its electrodes. The constant of proportionality, C, is the capacitance. The SI unit of capacitance is the farad. 1 farad = 1 F = 1 coulomb/volt = 1 C/V.
14 Capacitance and Capacitors Capacitance depends on the shape, size, and spacing of the two electrodes. A capacitor with a large capacitance holds more charge for a given potential difference than one with a small capacitance.
15 Charging a Capacitor To charge a capacitor, we need to move charge from one electrode to the other. The simplest way to do this is to use a source of potential difference such as a battery. A battery uses its internal chemistry to maintain a fixed potential difference between its terminals.
16 Charging a Capacitor
17 Charging a Capacitor
18 Charging a Capacitor A capacitor can be used to store charge.
19 QuickCheck What is the capacitance of these two electrodes? 8 nf 4 nf 2 nf 1 nf Some other value
20 QuickCheck What is the capacitance of these two electrodes? 8 nf 4 nf 2 nf 1 nf Some other value
21 Example Charging a capacitor A 1.3 µf capacitor is connected to a 1.5 V battery. What is the charge on the capacitor? PREPARE Charge flows through the battery from one capacitor electrode to the other until the potential difference V C between the electrodes equals that of the battery, or 1.5 V.
22 Example Charging a capacitor (cont.) SOLVE The charge on the capacitor is given by Equation 21.18: Q = C V C = ( F)(1.5 V) = C ASSESS This is the charge on the positive electrode; the other electrode has a charge of C.
23 The Parallel-Plate Capacitor A parallel-plate capacitor is important because it creates a uniform electric field between its flat electrodes. The electric field of a parallel-plate capacitor is A is the surface area of the electrodes, and Q is the charge on the capacitor.
24 The Parallel-Plate Capacitor The electric field strength of a parallel-plate capacitor is related to the potential difference ΔV and plate spacing d by Comparing the different equations describing the electric field of a parallel-plate capacitor we find Or equivalently,
25 The Parallel-Plate Capacitor
26 QuickCheck A capacitor has a charge Q. The plates are then pulled apart so that the distance between them is larger. After the plates are pulled apart, The charge increases and the electric field decreases. The charge decreases and the electric field increases. Both the charge and the field increase. Both the charge and the field decrease. The charge and the field remain constant.
27 QuickCheck A capacitor has a charge Q. The plates are then pulled apart so that the distance between them is larger. After the plates are pulled apart, The charge increases and the electric field decreases. The charge decreases and the electric field increases. Both the charge and the field increase. Both the charge and the field decrease. The charge and the field remain constant.
28 QuickCheck A capacitor is attached to a battery. The plates are then pulled apart so that the distance between them is larger. After the plates are pulled apart, The charge increases and the electric field decreases. The charge decreases and the electric field increases. Both the charge and the field increase. Both the charge and the field decrease. The charge and the field remain constant.
29 QuickCheck A capacitor is attached to a battery. The plates are then pulled apart so that the distance between them is larger. After the plates are pulled apart, The charge increases and the electric field decreases. The charge decreases and the electric field increases. Both the charge and the field increase. Both the charge and the field decrease. The charge and the field remain constant.
30 Example Problem A parallel-plate capacitor is constructed of two square plates, 1 m on each side, separated by a 1.0 mm gap. What is the capacitance of this capacitor? If it were charged to 100 V, how much charge would be on the capacitor?
31 Example Charging a parallel-plate capacitor The spacing between the plates of a 1.0 µf parallel-plate capacitor is mm. a. What is the surface area of the plates? b. How much charge is on the plates if this capacitor is attached to a 1.5 V battery?
32 Example Charging a parallel-plate capacitor (cont.) SOLVE a. From the definition of capacitance, b. The charge is Q = C V C = ( F)(1.5 V) = C = 1.5 µc.
33 Example Charging a parallel-plate capacitor (cont.) ASSESS The surface area needed to construct a 1.0 µf capacitor (a fairly typical value) is enormous and hardly practical. We ll see in the next section that real capacitors can be reduced to a more manageable size by placing an insulator between the capacitor plates.
34 Dielectrics and Capacitors An insulator consists of vast numbers of atoms. When an insulator is placed in an electric field, each atom polarizes. Polarization occurs when an atom s negative electron cloud and positive nucleus shift very slightly in opposite directions in response to an applied electric field. An induced positive charge builds up on one surface of the insulator, and an induced negative charge builds up on the other surface.
35 Dielectrics and Capacitors
36 Dielectrics and Capacitors The induced charge on an insulator will create a uniform electric field, like in a parallel-plate capacitor, but one that is directed opposite to the applied electric field. A dielectric is an insulator placed between the plates of a capacitor. A capacitor s electric field polarizes the dielectric; the dielectric creates an electric field of its own opposite the capacitor s field. The two fields add to give a net field in the same direction as the applied field, but smaller. Thus the electric field between the capacitor plates is smaller with a dielectric.
37 Dielectrics and Capacitors
38 Dielectrics and Capacitors When a dielectric is inserted, the electric field between the plates decreases, which implies the potential difference decreases as well. The charge remains the same. The capacitance C = Q/ΔV C increases. The presence of a dielectric results in an increased capacitance. The dielectric constant κ of the material determines the factor by which the capacitance is increased: C 0 is the capacitance without a dielectric present.
39 Dielectrics and Capacitors
40 Example Finding the dielectric constant A parallel-plate capacitor is charged using a 100 V battery; then the battery is removed. If a dielectric slab is slid between the plates, filling the space inside, the capacitor voltage drops to 30 V. What is the dielectric constant of the dielectric?
41 Example Finding the dielectric constant (cont.) PREPARE The capacitor voltage remains ( V C ) 1 = 100 V when it is disconnected from the battery. Placing the dielectric between the plates reduces the voltage to ( V C ) 2 = 30 V. Because the plates are not connected when the dielectric is inserted, the charge on the plates remains constant.
42 Example Finding the dielectric constant (cont.) SOLVE Because the plates are not connected, the charge on the capacitor is constant, so we have Q 1 = C 1 ( V C ) 1 = Q 2 = C 2 ( V C ) 2 Inserting the dielectric increases the capacitance by a factor of κ, so that C 2 = κc 1.
43 Example Finding the dielectric constant (cont.) Thus C 1 ( V C ) 1 = κc 1 ( V C )2 or, canceling C 1, ( V C ) 1 = κ( V C ) 2. The dielectric constant is then ASSESS The dielectric constant is greater than 1, as must be the case.
44 Example Problem A parallel-plate capacitor with a capacitance of 200 pf is charged to 100 V. Then the battery is removed. A sheet of teflon (κ = 2.0) is then slid between the plates. A. By what factor does the charge on the plates change? B. What is the final potential difference between the plates?
45 Section 21.8 Energy and Capacitors
46 Energy and Capacitors A charged capacitor stores energy as electric potential energy. The potential energy U C stored in a charged capacitor is Since, Q = CΔV C, the electric potential can be written
47 Example Problem The capacitor bank used to power a large electromagnet is charged to 23,500 V and stores 8.4 MJ of energy. What is the total capacitance of the capacitor bank?
48 Example Energy in a camera flash How much energy is stored in a 220 µf camera-flash capacitor that has been charged to 330 V? What is the average power delivered to the flash lamp if this capacitor is discharged in 1.0 ms?
49 Example Energy in a camera flash (cont.) SOLVE The energy stored in the capacitor is If this energy is released in 1.0 ms, the average power is
50 Example Energy in a camera flash (cont.) ASSESS The stored energy is equivalent to raising a 1 kg mass by 1.2 m. This is a rather large amount of energy; imagine the damage a 1 kg object could do after falling 1.2 m. When this energy is released very quickly, as is possible in an electronic circuit, the power is very high.
51 Energy and Capacitors A capacitor can charge very slowly and then can release the energy very quickly. A medical application of this ability to rapidly deliver energy is the defibrillator. Fibrillation is the state in which the heart muscles twitch and cannot pump blood. A defibrillator is a large capacitor that can store up to 360 J of energy and release it in 2 milliseconds. The large shock can sometimes stop fibrillation.
52 The Energy in the Electric Field The energy stored in the capacitor is The energy is stored in the capacitor s electric field.
53 The Energy in the Electric Field
54 The Energy in the Electric Field Because the quantity Ad, the volume inside the capacitor, is the volume in which the energy is stored, we can define the energy density u E of the electric field: The energy density has units J/m 3.
55 QuickCheck A capacitor charged to 1.5 V stores 2.0 mj of energy. If the capacitor is charged to 3.0 V, it will store 1.0 mj 2.0 mj 4.0 mj 6.0 mj 8.0 mj
56 QuickCheck A capacitor charged to 1.5 V stores 2.0 mj of energy. If the capacitor is charged to 3.0 V, it will store 1.0 mj 2.0 mj 4.0 mj 6.0 mj 8.0 mj U C µ (DV) 2
57 Example Finding the energy density for a defibrillator A defibrillator unit contains a 150 µf capacitor that is charged to 2000 V. The capacitor plates are separated by a mm-thick dielectric with κ = 300. a. What is the total area of the capacitor plates? b. What is the energy density stored in the electric field when the capacitor is charged? PREPARE Assume the capacitor can be modeled as a parallel-plate capacitor with a dielectric.
58 Example Finding the energy density for a defibrillator (cont.) SOLVE a. The surface area of the electrodes is b. The electric field strength is
59 Example Finding the energy density for a defibrillator (cont.) Consequently, the energy density in the electric field is
60 Example Finding the energy density for a defibrillator (cont.) ASSESS For comparison, the energy density of gasoline is about J/m 3, about 60 times higher than this capacitor. Capacitors store less energy than some other devices, but they can deliver this energy very rapidly.
61 Section 22.1 A Model of Current
62 A Model of a Current If we connect the two capacitor plates of a parallel-plate capacitor with a metal wire, the plates become neutral. The capacitor has been discharged.
63 A Model of a Current The motion of charges through a material is called a current. If we observe a capacitor discharge, we see other effects. As the capacitor discharges, the connecting wire gets warmer.
64 A Model of a Current As the capacitor discharges, if the wire is very thin in places like the filament of a lightbulb, the wire gets hot enough to glow. More current means a brighter bulb.
65 Charge Carriers The charges that move in a current are called charge carriers. In a metal, the charge carriers are electrons. It is the motion of the conduction electrons, which are free to move around, that forms a current in the metal.
66 Charge Carriers An insulator does not have free charges and cannot carry a current. Other materials may have different charge carriers. Both positive and negative ions carry charge in ionic solutions such as seawater, blood, and intercellular fluids.
67 Creating a Current When we apply an electric field to a metal, the field exerts a force on the electrons and they begin to accelerate. Collisions between the electrons and the atoms of the metal slow them down, transforming the electron s kinetic energy into thermal energy, making the metal warmer. The motion of the electrons will cease unless you continue pushing by maintaining an electric field. In a constant field, an electron s average motion will be opposite the field. The motion is the electron s drift velocity.
68 Creating a Current
69 Creating a Current In a parallel-plate capacitor, the initial separation of charges creates a potential difference between the plates. Connecting a wire between the plates establishes an electric field in the wire, which causes electrons to flow from the negative plate (which has an excess of electrons) toward the positive plate. The potential difference creates the electric field that drives the current in the wire. Eventually the plates will be completely discharged, meaning no more potential difference, no more field, and no more current.
70 Creating a Current
71 Creating a Current The current at point B is exactly equal to the current at point A. The current leaving a lightbulb is exactly the same as the current entering the lightbulb.
72 Creating a Current The lightbulb cannot destroy electrons without violating the law of conservation of mass and the law of conservation of charge. Thus, the number of electrons is not changed by the lightbulb. The lightbulb cannot store electrons, or it would become increasingly negative until its repulsive force would stop the flow of new electrons and the bulb would go out. Every electron entering the lightbulb is matched by an electron leaving the lightbulb, and thus the currents on either side of a lightbulb are equal.
Intermediate Physics PHYS102
Intermediate Physics PHYS102 Dr Richard H. Cyburt Assistant Professor of Physics My office: 402c in the Science Building My phone: (304) 384-6006 My email: rcyburt@concord.edu My webpage: www.concord.edu/rcyburt
Intermediate Physics PHYS102
Intermediate Physics PHYS102 Dr Richard H. Cyburt Assistant Professor of Physics My office: 402c in the Science Building My phone: (304) 384-6006 My email: rcyburt@concord.edu My webpage: www.concord.edu/rcyburt
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
Chapter 21 Electric Potential
Chapter 21 Electric Potential Chapter Goal: To calculate and use the electric potential and electric potential energy. Slide 21-1 Chapter 21 Preview Looking Ahead Text: p. 665 Slide 21-2 Review of Potential
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
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
Chapter 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 energy-storing
Intermediate Physics PHYS102
Intermediate Physics PHYS102 Dr Richard H. Cyburt Assistant Professor of Physics My office: 402c in the Science Building My phone: (304) 384-6006 My email: rcyburt@concord.edu My webpage: www.concord.edu/rcyburt
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
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 16. Electric Energy and Capacitance
Chapter 16 Electric Energy and Capacitance Electric Potential of a Point Charge The point of zero electric potential is taken to be at an infinite distance from the charge The potential created by a point
Chapter 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
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
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
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
Chapter 8. Capacitors. Charging a capacitor
Chapter 8 Capacitors You can store energy as potential energy by pulling a bowstring, stretching a spring, compressing a gas, or lifting a book. You can also store energy as potential energy in an electric
PHY101: Major Concepts in Physics I. Photo: J. M. Schwarz
Welcome back to PHY101: Major Concepts in Physics I Photo: J. M. Schwarz Announcements In class today we will finish Chapter 17 on electric potential energy and electric potential and perhaps begin Chapter
Parallel 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!
Section 16.1 Potential Difference and Electric Potential
PROBLEMS 1, 2, 3 = straightforward, intermediate, challenging = full solution available in Student Solutions Manual/Study Guide = biomedical application Section 16.1 Potential Difference and Electric Potential
Chapter 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
Chapter 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
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)
Capacitors and more. Lecture 9. Chapter 29. Physics II. Course website:
Lecture 9 Chapter 29 Physics II Capacitors and more Course website: http://faculty.uml.edu/andriy_danylov/teaching/physicsii Lecture Capture: http://echo360.uml.edu/danylov201415/physics2spring.html The
Capacitors and more. Lecture 9. Chapter 29. Physics II. Course website:
Lecture 9 Chapter 29 Physics II Capacitors and more Course website: http://faculty.uml.edu/andriy_danylov/teaching/physicsii Lecture Capture: http://echo360.uml.edu/danylov201415/physics2spring.html The
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
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
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
Intermediate Physics PHYS102
Intermediate Physics PHYS102 Dr Richard H. Cyburt Assistant Professor of Physics My office: 402c in the Science Building My phone: (304) 384-6006 My email: rcyburt@concord.edu My webpage: www.concord.edu/rcyburt
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 =
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
Chapter 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
Chapter 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
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
General Physics II (PHYS 104) Exam 2: March 21, 2002
General Physics II (PHYS 104) Exam 2: March 21, 2002 Name: Multiple Choice (3 points each): Answer the following multiple choice questions. Clearly circle the response (or responses) that provides the
Chapter Assignment Solutions
Chapter 20-21 Assignment Solutions Table of Contents Page 558 #22, 24, 29, 31, 36, 37, 40, 43-48... 1 Lightning Worksheet (Transparency 20-4)... 4 Page 584 #42-46, 58-61, 66-69, 76-79, 84-86... 5 Chapter
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/
STATIC ELECTRICITY & CAPACITANCE: Solutions to higher level questions
STATIC ELECTRICITY & CAPACITANCE: Solutions to higher level questions 2015 Question 8 (i) Define electric field strength. E = force per unit charge (ii) Draw a labelled diagram of a gold leaf electroscope.
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
Electric 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
Physics 115. Energy in E fields Electric Current Batteries Resistance. General Physics II. Session 21
Physics 115 General Physics II Session 21 Energy in E fields Electric Current Batteries Resistance R. J. Wilkes Email: phy115a@u.washington.edu Home page: http://courses.washington.edu/phy115a/ 5/6/14
Capacitance 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
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 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
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.
Physics 196 Final Test Point
Physics 196 Final Test - 120 Point Name You need to complete six 5-point problems and six 10-point problems. Cross off one 5-point problem and one 10-point problem. 1. Two small silver spheres, each with
F 13. The two forces are shown if Q 2 and Q 3 are connected, their charges are equal. F 12 = F 13 only choice A is possible. Ans: Q2.
Q1. Three fixed point charges are arranged as shown in Figure 1, where initially Q 1 = 10 µc, Q = 15 µc, and Q 3 = 5 µc. If charges Q and Q 3 are connected by a very thin conducting wire and then disconnected,
Nicholas J. Giordano. Chapter 18. Electric Potential. Marilyn Akins, PhD Broome Community College
Nicholas J. Giordano www.cengage.com/physics/giordano Chapter 18 Electric Potential Marilyn Akins, PhD Broome Community College Electric Potential Electric forces can do work on a charged object Electrical
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
12/15/2015. Newton per Coulomb N/C. vector. A model of the mechanism for electrostatic interactions. The Electric Field
Chapter 15 Lecture The Electric Field A model of the mechanism for electrostatic interactions A model for electric interactions, suggested by Michael Faraday, involves some sort of electric disturbance
Intermediate Physics PHYS102
Intermediate Physics PHYS102 Dr Richard H. Cyburt Assistant Professor of Physics My office: 402c in the Science Building My phone: (304) 384-6006 My email: rcyburt@concord.edu My webpage: www.concord.edu/rcyburt
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
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.
Chapter 19: Electric Potential & Potential Energy
Chapter 9: Electric Potential & Potential Energy Brent Royuk Phys-2 Concordia University Terminology Two Different uantities: Electric Potential and Electric Potential Energy Electric Potential = Voltage
104 Practice Exam 1-2/21/02
104 Practice Exam 1-2/21/02 1. One mole of a substance contains 6.02 > 10 23 protons and an equal number of electrons. If the protons could somehow be separated from the electrons and placed in separate
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
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.
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,
!"#$%"&'$"()#*(+*,-.%/0
!"#$%"&'$"()#*(*,-.%/0 Often we encounter distributions of charge - not single charges Examples: Charges on wires in circuits Charges in electronic components Charges in the ionosphere and solar wind Charges
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
LAST Name (print) ALL WORK MUST BE SHOWN FOR THE FREE RESPONSE QUESTION IN ORDER TO RECEIVE FULL CREDIT.
Physics 107 LAST Name (print) First Mid-Term Exam FIRST Name (print) Summer 2013 Signature: July 5 UIN #: Textbooks, cell phones, or any other forms of wireless communication are strictly prohibited in
Phys222 W16 Exam 2: Chapters Key. Name:
Name: Please mark your answer here and in the scantron. A positively charged particle is moving in the +y-direction when it enters a region with a uniform electric field pointing in the +y-direction. Which
10/14/2018. Current. Current. QuickCheck 30.3
Current If QCurrent is the total amount of charge that has moved past a point in a wire, we define the current I in the wire to be the rate of charge flow: The SI unit for current is the coulomb per second,
Phys102 Second Major-133 Zero Version Coordinator: A.A.Naqvi Tuesday, August 05, 2014 Page: 1
Coordinator: A.A.Naqvi Tuesday, August 05, 2014 Page: 1 Q1. igure 1 shows four situations in which a central proton (P) is surrounded by protons or electrons fixed in place along a half-circle. The angles
Chapter 20 Electric Potential and Electric Potential Energy
Chapter 20 Electric Potential and Electric Potential Energy 1 Overview of Chapter 20 Electric Potential Energy and the Electric Potential! Energy Conservation! The Electric Potential of Point Charges!
Physics 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 E-field has energy stored in it that can be useful Like other forms of
W05D1 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, 5.1-5.4 1 Outline Conductors and Insulators Conductors as
PH2200 Practice Exam II Summer 2003
PH00 Practice Exam II Summer 00 INSTRUCTIONS. Write your name and student identification number on the answer sheet and mark your recitation section.. Please cover your answer sheet at all times.. This
Introductory Physics PHYS101
Introductory Physics PHYS101 Dr Richard H. Cyburt Office Hours Assistant Professor of Physics My office: 402c in the Science Building My phone: (304) 384-6006 My email: rcyburt@concord.edu TRF 9:30-11:00am
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,
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
Electricity Mock Exam
Name: Class: _ Date: _ ID: A Electricity Mock Exam Multiple Choice Identify the letter of the choice that best completes the statement or answers the question.. What happens when a rubber rod is rubbed
the electrical nature of matter is inherent in its atomic structure E & M atoms are made up of p+, n, and e- the nucleus has p+ and n
Electric Forces and Fields E & M the electrical nature of matter is inherent in its atomic structure atoms are made up of p+, n, and e- a.k.a Electricity and Magnetism the nucleus has p+ and n surrounding
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
Phys102 Second Major-181 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),
Chapter 30: Potential and Field. (aka Chapter 29 The Sequel )
Chapter 30: Potential and Field (aka Chapter 29 The Sequel ) Electric Field and Electric Potential: Two Sides of the Same Coin A set of charges ( source charges ) alters the space around them. This alteration
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
Circuits Gustav Robert Kirchhoff 12 March October 1887
Welcome Back to Physics 1308 Circuits Gustav Robert Kirchhoff 12 March 1824 17 October 1887 Announcements Assignments for Thursday, October 18th: - Reading: Chapter 28.1-28.2, 28.4 - Watch Video: https://youtu.be/39vkt4cc5nu
Lecture 24 Chapter 22 Electrostatics II Electric Field & Potential. Chapter 23 Electric Current. From last time--
Lecture 24 Chapter 22 Electrostatics II Electric Field & Potential Chapter 23 Electric Current 21-Oct-10 From last time-- Electric charge (q), measured in Coulombs (C) Positive and negative charge Electric
Experiment 8: Capacitance and the Oscilloscope
Experiment 8: Capacitance and the Oscilloscope Nate Saffold nas2173@columbia.edu Office Hour: Mondays, 5:30PM-6:30PM @ Pupin 1216 INTRO TO EXPERIMENTAL PHYS-LAB 1493/1494/2699 Outline Capacitance: Capacitor
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
Definition 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
7. Static Electricity and Capacitance
Leaving Cert Physics Long Questions 2017-2002 7. Static Electricity and Capacitance Please remember to photocopy 4 pages onto one sheet by going A3 A4 and using back to back on the photocopier Contents
Physics 2135 Exam 2 October 18, 2016
Exam Total / 200 Physics 2135 Exam 2 October 18, 2016 Printed Name: Rec. Sec. Letter: Five multiple choice questions, 8 points each. Choose the best or most nearly correct answer. 1. A light bulb having
Exam 1 Solutions. The ratio of forces is 1.0, as can be seen from Coulomb s law or Newton s third law.
Prof. Eugene Dunnam Prof. Paul Avery Feb. 6, 007 Exam 1 Solutions 1. A charge Q 1 and a charge Q = 1000Q 1 are located 5 cm apart. The ratio of the electrostatic force on Q 1 to that on Q is: (1) none
Which one of the pipes emits sound with the lowest frequency? Which one of the pipes emits sound with the next lowest frequency?
The figures show standing waves of sound in six organ pipes of the same length. Each pipe has one end open and the other end closed. Warning: some of the figures show situations that are not possible.
BROCK UNIVERSITY. Physics 1P22/1P92. Mid-term Test 2: 19 March Solutions
BROCK UNIVERSITY Physics 1P22/1P92 Mid-term Test 2: 19 March 2010 Solutions 1. [6 marks] (See Page 746, CP # 24, and pages 15 16 of the posted Ch. 22 lecture notes from 4 March.) A 3.0 V potential difference
Reading: Electrostatics 3. Key concepts: Capacitance, energy storage, dielectrics, energy in the E-field.
Reading: Electrostatics 3. Key concepts: Capacitance, energy storage, dielectrics, energy in the E-field. 1.! Questions about charging and discharging capacitors. When an uncharged capacitor is connected
Electrical Energy and Capacitance
6 Electrical Energy and Capacitance QUICK QUIZZES. Choice. The field exerts a force on the electron, causing it to accelerate in the direction opposite to that of the field. In this process, electrical
[1] (b) Fig. 1.1 shows a circuit consisting of a resistor and a capacitor of capacitance 4.5 μf. Fig. 1.1
![[1] (b) Fig. 1.1 shows a circuit consisting of a resistor and a capacitor of capacitance 4.5 μf. Fig. 1.1](/thumbs/81/83276652.jpg "[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
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
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
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
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
2000 February 25 Exam I Physics 106
February 5 Exam I Physics 6 ircle the letter of the single best answer. Each question is worth point Physical onstants: proton charge = e =.6 9 proton mass = m p =.67 7 kg electron mass = m e = 9. kg permittivity
Electricity 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
Phys2120 Spring 2017 Practice Exam 1. Chapters Name
Name 1. Two point charges are 4 cm apart. They are moved to a new separation of 2 cm. By what factor does the resulting mutual force between them change? 2. An uncharged conductor is supported by an insulating
DC Circuits. Circuits and Capacitance Worksheet. 10 Ω resistance. second? on the sodium is the same as on an electron, but positive.
Circuits and Capacitance Worksheet DC Circuits 1. A current of 1.30 A flows in a wire. How many electrons are flowing past any point in the wire per second? 2. What is the current in amperes if 1200 Na
Study Guide #2. L. Colonna-Romano/T. Keil. Electricity and Magnetism
PH1120 Electricity and Magnetism L. Colonna-Romano/T. Keil Term B99 Study Guide #2 With this Study Guide, we will discuss work and energy in situations involving an electric field and related concepts.
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
Capacitors. HPP Activity 68v1. Charge Inside the Body A Close Look at Cell Membranes
HPP Activity 68v1 Capacitors Charge Inside the Body A Close Look at Cell Membranes Our bodies store and use charge to transmit signals across nerves and to tell certain cells what to do and when to do
General 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
Sharpen 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