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


 Bertha Porter
 3 years ago
 Views:
Transcription
1 ENERGY AND TIME CONSTANTS IN RC CIRCUITS By: Iwana Loveu Student No Lab Section: 0003 Date: February 8, 2004
2 Abstract: Two charged conductors consisting of equal and opposite charges forms the basis of a capacitor. The capacitor is a device used to store charge and energy. The capacitor can be charged with equal and opposite charges by connecting the conductors to the terminals of a power supply. Once the battery is disconnected, the charges remain in the conductor and can be discharged. The focus of this experiment is on the discharging and charging of a 1 farad capacitor. It is confirmed in this experiment that there is a direct relation between resistance and the time required (time constant) for a capacitor to reach a maximum or minimum voltage. The time constants calculated in this experiment were 28.57s and 47.62s for discharge to 30 Ω and 60 Ω respectively. Energy of the capacitor was also analyzed and found to be J and J. Theory: How much charge a capacitor can store depends on the voltage developed across the conductors of the capacitors. That is, the amount of charge stored in the capacitor is directly proportional to the voltage drop across the capacitor. Thus, by charging the capacitor, current (which is the flow of charge) moves from the power supply or the battery to the capacitor. The equal and opposite charge to each conductor develops a voltage drop across the capacitor. This voltage V across capacitor allows for electric potential energy U to exist in the capacitor because work is done to move charges from a source to the capacitor. This relation is given below in Equation 1. 1 CV 2 U = 2 [1] However, during the charging of the capacitor, the maximum voltage V is not achieved instantaneously, but requires some time. This is caused by the effect of electrical inertia
3 due to the fact that when charging begins, at time t = 0, the capacitor behaves almost like a wire with nearly zero resistance. Thus there is small time delay in reaching maximum potential V. During the charging of the capacitor, an initial voltage drop, v develops. This voltage v continues to increase over a period of time, t as more charge is transferred from the source. The voltage drop can therefore be described as function of time, given by Equation 2 below, where R is the total effective resistance of the circuit. The term R C is called the time constant and represents the amount time it takes for the potential difference across the capacitor to rise within 1/e of V. t = R' C v( t ) V 1 e [2] To now discharge the capacitor to a minimum potential difference v from maximum potential difference V also requires some time. This is given by Equation 3 where R is the total load resistance in the circuit. v( t ) = Ve... [3] The term RC again is the time constant, τ and is the time required for the voltage to drop from a maximum voltage V to a voltage 1/e of V (Equation 4). τ = RC [4] Apparatus: For the experiment, an MW 12V power supply connected to a circuit box is required. The circuit box is then connected to a MacOS computer with LabPro. The LoggerPro software is used to log voltage over a course of time. The circuit box used in this experiment is shown below in Figure 1. t RC
4 Figure 1. Circuit Box Procedure and Results: U of T PHYA21S3 Laboratory Manual After checking that all equipment was connected in the right place, the capacitor was discharged to make sure minimum or zero potential was obtained. LoggerPro was then started and was used to log the potential increase across the capacitor for 120 seconds. Immediately after switching S1 from right to left to begin charging, the lamp in the circuit box (Figure 2) was observed to be very bright. This was expected since initially at t = 0 the capacitor has nearly zero resistance. And, over period of time, as voltage increased across the capacitor the bulb inside the circuit box became gradually dim. This was because the amount of current reaching the lamp decreases as more and more current is delivered to the capacitor. So the voltage drop across the capacitor reaches a maximum of 5 volts, and the lamp goes completely off. This occurs because no current is able to travel to the lamp. From LoggerPro it was noticed that it takes approximately 120 seconds for the capacitor to reach the maximum 5 voltage. Therefore charging is not instantaneous. Furthermore the charge curve obtained from LoggerPro, was very similar to that of an exponential curve, so therefore maximum voltage is achieved exponentially. Once LoggerPro had stopped collecting, switch S1 was moved to the right to allow the capacitor to discharge with the 60Ω resistor. And LoggerPro was used once
5 again to log voltage against time. It was noticed that the capacitor does not discharge completely in 120 seconds. In addition, the capacitor seems to charge faster then it discharges. This is due to the different time constants during the charging and discharging of the capacitors. This time constant can be calculated directly from Equation 4, as shown. So theoretically, the time constant that should be expected for discharging the capacitor from a maximum voltage V to a lower voltage V/e should take 60 seconds. To verify if this is true, the time constant was calculated from the measurements of the voltage taken by LoggerPro. And the data obtained during discharging from LoggerPro appeared to be an exponential (decay). So the data was then fitted using a natural exponential function of the form: f ( x ) = Ae C x + inverse exponential function: B. Similarly the charging curve was also fitted, but using an f ( are illustrated below in Figure 3. τ = RC = 60Ω 1F = 60 sec C x x ) = A( 1 e ) + B. The data logged and fits acquired Figure 2. LoggerPro Data & Fits for Charging and Discharging (With 60 Ω )
6 For the data obtained during the discharge, the exact equation used by LoggerPro to fit the curve was: x f ( x ) =. e From this equation, the constant C was found to be Since this equation is almost the same as Equation 3, then C is equivalent to one over the time constant. The units for time constant were also determined from the theoretical equation. = s Therefore, the time constant obtained for discharging the capacitor was approximately seconds. 1 C = τ = τ τ = sec Following this, the next step was to determine the amount of energy stored in the capacitor. Since the capacitance of the capacitor is 1 farad and the maximum voltage reached was 5V then the energy (Equation 1) expected to be stored in the capacitor is: 1 U = 1 CV 2 = 1. 00F 5. 00V = 12. 5J 2 2 To determine if this was true, LoggerPro was used to graph the power (which is V 2 /R, where R in this case is 60 Ω ) against time. Since power is the transfer of energy in a unit time, then finding the area under the curve for the graph of Power versus Time would result in total energy transferred. So LoggerPro was used once again to calculate the integral of the graphed function. The integral (energy) of the curve of Power versus Time was approximately Joules. τ = RC unit for time constant = Ω F R has units Ω, C has units F V = A C = This entire process was repeated again by first charging the capacitor and then discharging it with the 30 Ω resistor (by moving switch S2 to the left). The theoretical C s C V = C A
7 time constant with the 30 Ω resistor was determined to be 30.0 seconds. The equation of the fit as shown below (Figure 4) was obtained for discharging: f ( x ) = e x Figure 2. LoggerPro Data & Fits for Charging and Discharging (With 60 Ω ) From this equation the time constant was determined experimentally to be 28.57seconds. Similarly, the same procedures were used as mentioned above to calculate the energy of the capacitor. Theoretically, the capacitor had gained 12.5 joules of energy again when charged to the maximum voltage of 5 volts. To verify this, the integral of the Power versus Time curve was taken again. This is the energy of the capacitor and was found to be approximately Joules. Discussion of Error: The experimental time constant (47.62 sec) to discharge the capacitor to the 60 Ω resistor was off by 20.6% from the expected value of 60 seconds. This large error may have been caused because all of the current was not reaching one or both resistors. A
8 possibility existed that current was leaving the circuit, perhaps because there were ionized particles in the circuit box that may have allowed the electron to leave the circuit. However, for the discharging of the capacitor to 30 Ω resistor, the experimental time constant (28.57s) was very close to the theoretical time constant (30s). The difference was less then 4.76% of the theoretical value. So it was most likely that not all of the current was reaching the resistor, or the capacitor was not initially charged to a maximum voltage. This same reason may account for the large difference between the experimental and the theoretical values in the energy of the capacitor. When the capacitor was initially charged, the power supply theoretically delivered 12.5 joules of energy to the capacitor. However, from the discharging with the 30 Ω and 60 Ω resistor, the energy of the capacitor was found to be only J (differs by 13.6%) and J (differs by 13.7%) respectively. This was mot likely caused by some energy dissipation to the surrounding. For example, when the capacitor was being charged, the lamp was initially on, so some of the energy is dissipated as heat through the lamp into the air. Other sources of error may have accumulated from systematic errors such the LoggerPro, which may have given an unsuitable fit, which would give different time constant. Conclusion: In this experiment the time constants of 28.57s for 30 Ω resistor and 47.62s for 60 Ω were obtained with 4.76% and 20.3% difference from the theoretical value. Although the time constants obtained were not exactly as expected, this experiment shows that the time constant is proportional to resistance. So when resistance is
9 increased by a factor of 2, time constant should also increase by a factor of 2 (assuming that the capacitance is constant). This explains why discharging is slower then charging the capacitor. During charging, there is a small total resistance of the lamp plus the power supply and during discharging, there is a resistance of the load resistor (30 Ω or 60 Ω ). Since the resistance during charging is smaller then the resistance during discharging, a larger time constant is obtained for discharging. Because of the larger time constant during discharge, it takes longer for the voltage to decay. Another conclusion that can be made is that the energy of the capacitor does not seem to depend on resistance, but only on the voltage of the source. This is evident from the experiment because the energy of the capacitor was nearly the same: J and J. The two values only differ by 0.01, which can be counted as experimental error.
[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
More informationPhysics Investigation 10 Teacher Manual
Physics Investigation 10 Teacher Manual Observation When a light bulb is connected to a number of charged capacitors, it lights up for different periods of time. Problem What does the rate of discharging
More informationLab 10: DC RC circuits
Name: Lab 10: DC RC circuits Group Members: Date: TA s Name: Objectives: 1. To understand current and voltage characteristics of a DC RC circuit 2. To understand the effect of the RC time constant Apparatus:
More informationOn the axes of Fig. 4.1, carefully sketch a graph to show how the potential difference V across the capacitor varies with time t. Label this graph L.
1 (a) A charged capacitor is connected across the ends of a negative temperature coefficient (NTC) thermistor kept at a fixed temperature. The capacitor discharges through the thermistor. The potential
More informationUniversity of TN Chattanooga Physics 1040L 8/18/2012 PHYSICS 1040L LAB LAB 4: R.C. TIME CONSTANT LAB
PHYSICS 1040L LAB LAB 4: R.C. TIME CONSTANT LAB OBJECT: To study the discharging of a capacitor and determine the time constant for a simple circuit. APPARATUS: Capacitor (about 24 μf), two resistors (about
More informationCoulomb 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
More informationExperiment P43: RC Circuit (Power Amplifier, Voltage Sensor)
PASCO scientific Vol. 2 Physics Lab Manual: P431 Experiment P43: (Power Amplifier, Voltage Sensor) Concept Time SW Interface Macintosh file Windows file circuits 30 m 700 P43 P43_RCCI.SWS EQUIPMENT NEEDED
More informationName Class Date. RC Circuit Lab
RC Circuit Lab Objectives: Students will be able to Use the ScienceWorkshop interface to investigate the relationship between the voltage remaining across a capacitor and the time taken for the discharge
More informationExperiment 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.
More informationLaboratory 7: Charging and Discharging a Capacitor Prelab
Phys 132L Fall 2018 Laboratory 7: Charging and Discharging a Capacitor Prelab Consider a capacitor with capacitance C connected in series to a resistor with resistance R as shown in Fig. 1. Theory predicts
More informationPhysics 212 Midterm 2 Form A
1. A wire contains a steady current of 2 A. The charge that passes a cross section in 2 s is: A. 3.2 1019 C B. 6.4 1019 C C. 1 C D. 2 C E. 4 C 2. In a Physics 212 lab, Jane measures the current versus
More informationReview. 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.
More informationECE2262 Electric Circuits. Chapter 6: Capacitance and Inductance
ECE2262 Electric Circuits Chapter 6: Capacitance and Inductance Capacitors Inductors Capacitor and Inductor Combinations OpAmp Integrator and OpAmp Differentiator 1 CAPACITANCE AND INDUCTANCE Introduces
More informationEXPERIMENT 12 OHM S LAW
EXPERIMENT 12 OHM S LAW INTRODUCTION: We will study electricity as a flow of electric charge, sometimes making analogies to the flow of water through a pipe. In order for electric charge to flow a complete
More informationExercise 1: RC Time Constants
Exercise 1: RC EXERCISE OBJECTIVE When you have completed this exercise, you will be able to determine the time constant of an RC circuit by using calculated and measured values. You will verify your results
More informationEXPERIMENT 5A RC Circuits
EXPERIMENT 5A Circuits Objectives 1) Observe and qualitatively describe the charging and discharging (decay) of the voltage on a capacitor. 2) Graphically determine the time constant for the decay, τ =.
More informationSwitch. R 5 V Capacitor. ower upply. Voltmete. Goals. Introduction
Switch Lab 6. Circuits ower upply Goals + + R 5 V Capacitor V To appreciate the capacitor as a charge storage device. To measure the voltage across a capacitor as it discharges through a resistor, and
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 26 DirectCurrent Circuits
Chapter 26 DirectCurrent Circuits 1 Resistors in Series and Parallel In this chapter we introduce the reduction of resistor networks into an equivalent resistor R eq. We also develop a method for analyzing
More informationSwitch. R 5 V Capacitor. ower upply. Voltmete. Goals. Introduction
Switch Lab 6. Circuits ower upply Goals + + R 5 V Capacitor V To appreciate the capacitor as a charge storage device. To measure the voltage across a capacitor as it discharges through a resistor, and
More informationCapacitors GOAL. EQUIPMENT. CapacitorDecay.cmbl 1. Building a Capacitor
PHYSICS EXPERIMENTS 133 Capacitor 1 Capacitors GOAL. To measure capacitance with a digital multimeter. To make a simple capacitor. To determine and/or apply the rules for finding the equivalent capacitance
More informationLab 4 CAPACITORS & RC CIRCUITS
67 Name Date Partners Lab 4 CAPACITORS & RC CIRCUITS OBJECTIVES OVERVIEW To define capacitance and to learn to measure it with a digital multimeter. To explore how the capacitance of conducting parallel
More informationDEPARTMENT OF COMPUTER ENGINEERING UNIVERSITY OF LAHORE
DEPARTMENT OF COMPUTER ENGINEERING UNIVERSITY OF LAHORE NAME. Section 1 2 3 UNIVERSITY OF LAHORE Department of Computer engineering Linear Circuit Analysis Laboratory Manual 2 Compiled by Engr. Ahmad Bilal
More informationRC Circuit Lab  Discovery PSI Physics Capacitors and Resistors
1 RC Circuit Lab  Discovery PSI Physics Capacitors and Resistors Name Date Period Purpose The purpose of this lab will be to determine how capacitors behave in RC circuits. The manner in which capacitors
More informationChapter 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
More informationLab 4 RC Circuits. Name. Partner s Name. I. Introduction/Theory
Lab 4 RC Circuits Name Partner s Name I. Introduction/Theory Consider a circuit such as that in Figure 1, in which a potential difference is applied to the series combination of a resistor and a capacitor.
More informationPreLab Quiz / PHYS 224. RC Circuits. Your Name Lab Section
PreLab Quiz / PHYS 224 RC Circuits Your Name Lab Section 1. What do we investigate in this lab? 2. For the RC circuit shown in Figure 1 on Page 3, RR = 100 ΩΩ and CC = 1.00 FF. What is the time constant
More informationChapter 19 Lecture Notes
Chapter 19 Lecture Notes Physics 2424  Strauss Formulas: R S = R 1 + R 2 +... C P = C 1 + C 2 +... 1/R P = 1/R 1 + 1/R 2 +... 1/C S = 1/C 1 + 1/C 2 +... q = q 0 [1e t/(rc) ] q = q 0 e t/(rc τ = RC
More informationDirectCurrent Circuits. Physics 231 Lecture 61
DirectCurrent Circuits Physics 231 Lecture 61 esistors in Series and Parallel As with capacitors, resistors are often in series and parallel configurations in circuits Series Parallel The question then
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 informationAssessment Schedule 2016 Physics: Demonstrate understanding electrical systems (91526)
NCEA evel 3 Physics (91526) 2016 page 1 of 5 Assessment Schedule 2016 Physics: Demonstrate understanding electrical systems (91526) Evidence Statement NØ N1 N 2 A 3 A 4 M 5 M 6 E 7 E 8 0 1A 2A 3A 4A or
More informationIntroduction 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/
More informationAP 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 crosssectional area of the conductor changes. If a conductor has no current,
More informationDEVIL PHYSICS THE BADDEST CLASS ON CAMPUS IB PHYSICS
DEVIL PHYSICS THE BADDEST CLASS ON CAMPUS IB PHYSICS LSN 3: CAPACITANCE Questions From Reading Activity? Essential Idea: Capacitors can be used to store electrical energy for later use. Nature Of Science:
More informationChapter 28 Direct Current Circuits
Chapter 28 Direct Current Circuits Multiple Choice 1. t what rate is thermal energy being generated in the 2resistor when = 12 V and = 3.0 Ω? 2 a. 12 W b. 24 W c. 6.0 W d. 3.0 W e. 1.5 W 2. t what rate
More informationChapter 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
More informationTactics Box 23.1 Using Kirchhoff's Loop Law
PH203 Chapter 23 solutions Tactics Box 231 Using Kirchhoff's Loop Law Description: Knight/Jones/Field Tactics Box 231 Using Kirchhoff s loop law is illustrated Learning Goal: To practice Tactics Box 231
More informationECE2262 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
More informationLAB 3: Capacitors & RC Circuits
LAB 3: Capacitors & C Circuits Name: Circuits Experiment Board Wire leads Capacitors, esistors EQUIPMENT NEEDED: Two Dcell Batteries Multimeter Logger Pro Software, ULI Purpose The purpose of this lab
More informationCurrent. I = ei e = en e Av d. The current, which is Coulomb s per second, is simply
Current The current, which is Coulomb s per second, is simply I = ei e = en e Av d e is the charge is the electron! ne is the density of electrons! A is the cross sectional area of the wire! vd is the
More informationLab 8 Simple Electric Circuits
Lab 8 Simple Electric Circuits INTRODUCTION When we talk about the current in a river, we are referring to the flow of water. Similarly, when we refer to the electric current in a circuit, we are talking
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 informationLab 5 CAPACITORS & RC CIRCUITS
L051 Name Date Partners Lab 5 CAPACITORS & RC CIRCUITS OBJECTIVES OVERVIEW To define capacitance and to learn to measure it with a digital multimeter. To explore how the capacitance of conducting parallel
More informationphysics 4/7/2016 Chapter 31 Lecture Chapter 31 Fundamentals of Circuits Chapter 31 Preview a strategic approach THIRD EDITION
Chapter 31 Lecture physics FOR SCIENTISTS AND ENGINEERS a strategic approach THIRD EDITION randall d. knight Chapter 31 Fundamentals of Circuits Chapter Goal: To understand the fundamental physical principles
More informationPhysics 24 Exam 2 March 18, 2014
Exam Total / 200 Physics 24 Exam 2 March 18, 2014 Printed Name: Rec. Sec. Letter: Five multiple choice questions, 8 points each. Choose the best or most nearly correct answer. 1. You need to store electrical
More informationLecture 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
More informationName: Lab Partner: Section:
Chapter 6 Capacitors and RC Circuits Name: Lab Partner: Section: 6.1 Purpose The purpose of this experiment is to investigate the physics of capacitors in circuits. The charging and discharging of a capacitor
More informationAssessment Schedule 2015 Physics: Demonstrate understanding of electrical systems (91526)
NCEA Level 3 Physics (91526) 2015 page 1 of 6 Assessment Schedule 2015 Physics: Demonstrate understanding of electrical systems (91526) Evidence Q Evidence Achievement Achievement with Merit Achievement
More informationAC 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
More informationLab 5  Capacitors and RC Circuits
Lab 5 Capacitors and RC Circuits L51 Name Date Partners Lab 5 Capacitors and RC Circuits OBJECTIVES To define capacitance and to learn to measure it with a digital multimeter. To explore how the capacitance
More informationPHYSICS 122 Lab EXPERIMENT NO. 6 AC CIRCUITS
PHYSICS 122 Lab EXPERIMENT NO. 6 AC CIRCUITS The first purpose of this laboratory is to observe voltages as a function of time in an RC circuit and compare it to its expected time behavior. In the second
More informationThe Basic Capacitor. Dielectric. Conductors
Chapter 9 The Basic Capacitor Capacitors are one of the fundamental passive components. In its most basic form, it is composed of two conductive plates separated by an insulating dielectric. The ability
More informationChapter 21 Electric Current and Direct Current Circuits
Chapter 21 Electric Current and Direct Current Circuits 1 Overview of Chapter 21 Electric Current and Resistance Energy and Power in Electric Circuits Resistors in Series and Parallel Kirchhoff s Rules
More information1) Two lightbulbs, one rated 30 W at 120 V and another rated 40 W at 120 V, are arranged in two different circuits.
1) Two lightbulbs, one rated 30 W at 120 V and another rated 40 W at 120 V, are arranged in two different circuits. a. The two bulbs are first connected in parallel to a 120 V source. i. Determine the
More informationRC, RL, and LCR Circuits
RC, RL, and LCR Circuits EK307 Lab Note: This is a two week lab. Most students complete part A in week one and part B in week two. Introduction: Inductors and capacitors are energy storage devices. They
More informationFigure 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
More informationCapacitance. 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
More information(b) State the relation between work, charge and potential difference for an electric circuit.
Question Bank on ChElectricity 1. (a) Define the S.I unit of potential difference. (b) State the relation between work, charge and potential difference for an electric circuit. Calculate the potential
More informationPractical 1 RC Circuits
Objectives Practical 1 Circuits 1) Observe and qualitatively describe the charging and discharging (decay) of the voltage on a capacitor. 2) Graphically determine the time constant for the decay, τ =.
More informationOld Dominion University Physics 112N/227N/232N Lab Manual, 13 th Edition
RC Circuits Experiment PH06_Todd OBJECTIVE To investigate how the voltage across a capacitor varies as it charges. To find the capacitive time constant. EQUIPMENT NEEDED Computer: Personal Computer with
More informationCAPACITORS / 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
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 informationB THE CAPACITOR. Theory
8. THE CAPACITOR You will study several aspects of a capacitor, how the voltage across it changes with time as it is being charged and discharged and how it stores energy. The most well known device for
More informationPHY222  Lab 7 RC Circuits: Charge Changing in Time Observing the way capacitors in RC circuits charge and discharge.
PHY222 Lab 7 RC Circuits: Charge Changing in Time Observing the way capacitors in RC circuits charge and discharge. Print Your Name Print Your Partners' Names You will return this handout to the instructor
More informationWhat happens when things change. Transient current and voltage relationships in a simple resistive circuit.
Module 4 AC Theory What happens when things change. What you'll learn in Module 4. 4.1 Resistors in DC Circuits Transient events in DC circuits. The difference between Ideal and Practical circuits Transient
More informationChapter 28 Solutions
Chapter 8 Solutions 8.1 (a) P ( V) R becomes 0.0 W (11.6 V) R so R 6.73 Ω (b) V IR so 11.6 V I (6.73 Ω) and I 1.7 A ε IR + Ir so 15.0 V 11.6 V + (1.7 A)r r 1.97 Ω Figure for Goal Solution Goal Solution
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 informationSwitch. R 5 V Capacitor. ower upply. Voltmete. Goals. Introduction
Switch Lab 9. Circuits ower upply Goals + + R 5 V Capacitor V To appreciate the capacitor as a charge storage device. To measure the voltage across a capacitor as it discharges through a resistor, and
More informationPhysics 2135 Exam 2 October 20, 2015
Exam Total / 200 Physics 2135 Exam 2 October 20, 2015 Printed Name: Rec. Sec. Letter: Five multiple choice questions, 8 points each. Choose the best or most nearly correct answer. 1. A straight wire segment
More informationELECTRICITY. Electric Circuit. What do you already know about it? Do Smarty Demo 5/30/2010. Electric Current. Voltage? Resistance? Current?
ELECTRICITY What do you already know about it? Voltage? Resistance? Current? Do Smarty Demo 1 Electric Circuit A path over which electrons travel, out through the negative terminal, through the conductor,
More informationCircuitsOhm's Law. 1. Which graph best represents the relationship between the electrical power and the current in a resistor that obeys Ohm s Law?
1. Which graph best represents the relationship between the electrical power and the current in a resistor that obeys Ohm s Law? 2. A potential drop of 50 volts is measured across a 250 ohm resistor.
More informationLab 08 Capacitors 2. Figure 2 Series RC circuit with SPDT switch to charge and discharge capacitor.
Lab 08: Capacitors Last edited March 5, 2018 Learning Objectives: 1. Understand the shortterm and longterm behavior of circuits containing capacitors. 2. Understand the mathematical relationship between
More informationECE2262 Electric Circuit
ECE2262 Electric Circuit Chapter 7: FIRST AND SECONDORDER RL AND RC CIRCUITS Response to FirstOrder RL and RC Circuits Response to SecondOrder RL and RC Circuits 1 2 7.1. Introduction 3 4 In dc steady
More informationCOPYRIGHTED MATERIAL. DC Review and PreTest. Current Flow CHAPTER
Kybett c0.tex V303/3/2008 8:44pm Page CHAPTER DC Review and PreTest Electronics cannot be studied without first understanding the basics of electricity. This chapter is a review and pretest on those
More informationLaboratory Worksheet Experiment NE04  RC Circuit Department of Physics The University of Hong Kong. Name: Student ID: Date:
PHYS1050 / PHYS1250 Laboratory Worksheet Experiment Department of Physics The University of Hong Kong Ref. (Staff Use) Name: Student ID: Date: Draw a schematic diagram of the charging RC circuit with ammeter
More informationElectric Currents. Resistors (Chapters 2728)
Electric Currents. Resistors (Chapters 2728) Electric current I Resistance R and resistors Relation between current and resistance: Ohm s Law Resistivity ρ Energy dissipated by current. Electric power
More informationVersion 001 CIRCUITS holland (1290) 1
Version CIRCUITS holland (9) This printout should have questions Multiplechoice questions may continue on the next column or page find all choices before answering AP M 99 MC points The power dissipated
More informationExercise 1: Capacitors
Capacitance AC 1 Fundamentals Exercise 1: Capacitors EXERCISE OBJECTIVE When you have completed this exercise, you will be able to describe the effect a capacitor has on dc and ac circuits by using measured
More informationScience Olympiad Circuit Lab
Science Olympiad Circuit Lab Key Concepts Circuit Lab Overview Circuit Elements & Tools Basic Relationships (I, V, R, P) Resistor Network Configurations (Series & Parallel) Kirchhoff s Laws Examples Glossary
More informationExperiment 4. RC Circuits. Observe and qualitatively describe the charging and discharging (decay) of the voltage on a capacitor.
Experiment 4 RC Circuits 4.1 Objectives Observe and qualitatively describe the charging and discharging (decay) of the voltage on a capacitor. Graphically determine the time constant τ for the decay. 4.2
More informationPhys 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 101 C / N m e
More informationPHYSICS 171 UNIVERSITY PHYSICS LAB II. Experiment 6. Transient Response of An RC Circuit
PHYSICS 171 UNIVERSITY PHYSICS LAB II Experiment 6 Transient Response of An RC Circuit Equipment: Supplies: Function Generator, Dual Trace Oscilloscope.002 Microfarad, 0.1 Microfarad capacitors; 1 Kilohm,
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 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
More informationChapter 7 DirectCurrent Circuits
Chapter 7 DirectCurrent Circuits 7. Introduction... 7. Electromotive Force... 7.3 Resistors in Series and in Parallel... 4 7.4 Kirchhoff s Circuit Rules... 6 7.5 VoltageCurrent Measurements... 8 7.6
More informationCapacitance, Resistance, DC Circuits
This test covers capacitance, electrical current, resistance, emf, electrical power, Ohm s Law, Kirchhoff s Rules, and RC Circuits, with some problems requiring a knowledge of basic calculus. Part I. Multiple
More informationCircuits 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 28.128.2, 28.4  Watch Video: https://youtu.be/39vkt4cc5nu
More informationControl of Rectified Direct Current Using Low Series Capacitance
Control of Rectified Direct Current Using Low Series Capacitance Parantap Nandi, Department of Electrical Engineering Ideal Institute Of Engineering, Kalyani, West Bengal University of Technology, West
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 informationSECTION #1  The experimental setup
Lemon Battery Connected in Series Charging a 2.2 Farad Capacitor SECTION #1  The experimental setup 1. The goal of this experiment is to see if I can connect 2, 3 or 4 lemons together in a series configuration
More informationEXPERIMENT 07 TO STUDY DC RC CIRCUIT AND TRANSIENT PHENOMENA
EXPERIMENT 07 TO STUDY DC RC CIRCUIT AND TRANSIENT PHENOMENA DISCUSSION The capacitor is a element which stores electric energy by charging the charge on it. Bear in mind that the charge on a capacitor
More informationPhysics 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
More informationElectricity and Light Pre Lab Questions
Electricity and Light Pre Lab Questions The pre lab questions can be answered by reading the theory and procedure for the related lab. You are strongly encouraged to answers these questions on your own.
More informationLab 5  Capacitors and RC Circuits
Lab 5 Capacitors and RC Circuits L51 Name Date Partners Lab 5 Capacitors and RC Circuits OBJECTIVES To define capacitance and to learn to measure it with a digital multimeter. To explore how the capacitance
More informationElectron Theory of Charge. Electricity. 1. Matter is made of atoms. Refers to the generation of or the possession of electric charge.
Electricity Refers to the generation of or the possession of electric charge. There are two kinds of electricity: 1. Static Electricity the electric charges are "still" or static 2. Current Electricity
More informationAgenda for Today. Elements of Physics II. Capacitors Parallelplate. Charging of capacitors
Capacitors Parallelplate 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
More informationIntroduction to Basic Electronics Lecture 2
Introduction to Basic Electronics Lecture 2 Basic Electronics What is electricity? Voltage, Current, Resistance DC/AC Ohm s Law Capacitors & Inductors Conductor & Insulator What is Electricity? Everything
More informationAlternating Currents. The power is transmitted from a power house on high voltage ac because (a) Electric current travels faster at higher volts (b) It is more economical due to less power wastage (c)
More informationPhysics 219 Question 1 January
Lecture 616 Physics 219 Question 1 January 30. 2012. A (nonideal) 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
More informationElectric Circuits. Overview. Hani Mehrpouyan,
Electric Circuits Hani Mehrpouyan, Department of Electrical and Computer Engineering, Lecture 15 (First Order Circuits) Nov 16 th, 2015 Hani Mehrpouyan (hani.mehr@ieee.org) Boise State c 2015 1 1 Overview
More information