Name Date: Course number: MAKE SURE TA & TI STAMPS EVERY PAGE BEFORE YOU START EXPERIMENT 9. Superconductivity & Ohm s Law

Save this PDF as:

Size: px
Start display at page:

Download "Name Date: Course number: MAKE SURE TA & TI STAMPS EVERY PAGE BEFORE YOU START EXPERIMENT 9. Superconductivity & Ohm s Law"

Transcription

1 Laboratory Section: Last Revised on January 6, 2016 Partners Names: Grade: EXPERIMENT 9 Superconductivity & Ohm s Law 0. Pre-Laboratory Work [2 pts] 1. Define the critical temperature for a superconducting material. Explain in words any method for measuring the critical temperature in a superconductor. (1 pt) 2. What is an ammeter? a voltmeter? What is the major difference in the way one uses each to measure electrical quantities in a simple electronic circuit? Be specific. (1 pt) TA or TI Signature 1 of 15

2 EXPERIMENT 9 Superconductivity & Ohm s Law 1. Purpose In the first part of this experiment you will observe a fundamental property of superconductors, the levitation of a magnet by a superconductor, illustrating the Meissner Effect. In the second part of the experiment, you will observe and verify Ohm s Law in simple resistive circuits. 2. Introduction 2.1 Superconductivity The flow of current in normal conductors dissipates energy producing heat. This "frictional" dissipation is measured by the resistivity of the material and is the origin of Ohm's Law. At lower temperatures some materials called superconductors lose all measurable electrical resistivity. Without any driving voltage, superconducting currents will flow indefinitely with no discernible decay. This phenomenon was originally discovered in 1911 by the Dutch physicist Heike Kamerlingh-Onnes (Nobel Prize: 1913). The superconducting transition (going from the normal, resistive state to a non-resistive, superconducting state) occurs over a relatively small change in temperature. The temperature at which it occurs, called the critical temperature T C, depends upon the material. Until recently, all known superconductors had a T C below 23K. The new ceramic superconductors (Nobel Prize: 1987) used in this experiment have much higher critical temperatures (90-100K). Since liquid nitrogen boils at 77K, the ceramic materials make superconducting phenomenon easily observable. The theoretical understanding of superconductivity in these materials is not entirely understood. Before the discovery of the ceramic superconductors in 1986, the accepted model was the BCS theory (Bardeen, Cooper and Schrieffer, Noble Prize 1957). According to this theory a superconducting current is carried by bound pairs of electrons (Cooper pairs) which move through a metal without energy dissipation. The mechanism for the new ceramic superconductors remains unknown and is the subject of much present day research. Another striking property of superconductors is that they are perfectly diamagnetic. When below the critical temperature, a superconductor will not allow any magnetic field to penetrate it. This is the Meissner Effect. Any external magnetic field which would penetrate the superconducting material is canceled by an opposing field produced by electric currents induced in the superconductor. If this external field comes from a magnet, then the expulsion results in a repulsive force on the magnet. The magnet, above the superconductor, will be levitated. This magnetic repulsion is a manifestation of the Meissner Effect. TA or TI Signature 2 of 15

3 2.2 Ohm s Law In simple resistive electronic circuits, Ohm s Law governs the relationship between voltage, current and resistance: V = IR Equation 9.1 Ohm s Law is a statement that there is a linear relationship between a driving voltage, V, and the resulting current, I, in an electrical circuit. The proportionality constant between voltage and current is the resistance of the circuit, R. Simple electronic circuits are usually made up of a direct current (DC) voltage supply, one that supplies a constant potential difference between 2 junctions in a circuit. A typical example is a battery. This DC voltage source is then hooked up to a combination of wires, individual resistors, and sometimes measuring devices like voltmeters and ammeters to measure voltage and current, respectively Commonly used resistors are carbon-based and are color-coded to allow easy identification. Individual resistors can be combined in two ways to form complicated circuits: parallel (see Figure 9.1) and series (see Figure 9.2). Resistors that are combined in series have their individual resistances add together for the total. In parallel, the inverse total resistance is the sum of the individual inverse resistances: Series = R + R + R... R TOTAL Equation Parallel = R R R R TOTAL Equation Parallel Combination R1 Series Combination R2 R2 R3 R1 R3 Figure 9.1 Figure 9.2 TA or TI Signature 3 of 15

4 3. Laboratory Work 3.1 Superconductivity PRECAUTIONS!!!! In this experiment you will handle liquid nitrogen which can cause severe "burns" because of its extremely low temperature. Certain precautions must be taken. You should read the following instructions carefully and practice these safety measures in the experiment. 1. Wear safety glasses at all times in the presence of liquid nitrogen (LN 2 ). 2. Do not allow any liquid nitrogen to touch your body, and do not touch anything that has been immersed in it until that item warms to room temperature. 3. Keep LN 2 away from the water. 4. Be extremely careful not to overfill or to spill liquid nitrogen from any vessel. Never store liquid nitrogen in a container with a tight-fitting lid because over pressure by the evaporated nitrogen may cause an explosion. 5. The superconductors are made of metal oxides that may be potentially toxic. For your safety, never handle the superconductor with your bare hands. Use the tweezers provided. Wash your hands with soap and water after the experiment is completed. As you can see, parts of this lab are potentially hazardous. However, by understanding the procedures and taking the precautions listed here, you can perform this lab safely. If you have any questions or are not sure how to be safe while doing this lab, please ask the lab TAs or TIs Experimental Set-Up 1. Set up the apparatus and various meters as shown in Figure 9.3 below. Set-up the multimeter to measure DC voltage and attach the wires to leads 3&4. Set to measure 20mV. Attach a voltmeter to leads 5&6, set to measure DC voltage in the mv range. Attach an ammeter to leads 8&9, set to measure DC current in the 10A range (make sure to not plug into the 200mA setting, as this could blow a fuse). Attach the 6V battery to leads 1&2. Set the current to maximum (around.3 A) by turning the potentiometer located below leads 1&2 to adjust the variable resistance. Make note of this value in Table 9.1a, as it will remain constant. 2. Cooling: Make sure the cork is secured in the foam, and the aluminum foil tray is under the drainage pipe. Pour liquid nitrogen over the superconductor to bring the temperature down past the critical temperature. You will be measuring the temperature of the superconductor via its thermal conductivity (measured by the multimeter connected to leads 3&4). As the superconductor cools, the conductivity should go from ~0mV at room temperature to ~6mV when it is in equilibrium with the liquid nitrogen. When the multimeter connected to leads 5&6 reads 0.0mV the superconductor is sufficiently cooled. TA or TI Signature 4 of 15

5 Name Date: Course number: Figure Using the tweezers, pick up one of the cubic magnets provided and place it on top of the superconductor disk. Try gently spinning the magnet with the tweezers. Observe whether the magnet is touching the surface of the disk. Be careful to not get your fingers or face close to the liquid nitrogen. Leave the cubic magnet there while continuing the experiment. 4. Warming: When ready to start taking data, USE THE TWEEZERS to remove the cork so the liquid nitrogen drains from your set-up. Be mindful of the liquid in the foil tray, and the tray itself which may get cold. 5. Measuring: As the superconductor warms, make recordings of the thermal conductivity (leads 3&4) and potential (leads 5&6) in Table 9.1a. Make sure to record where the voltage changes from 0.0 mv to 0.1 mv and then with every mv raise in potential until the voltage reads ~2mV. Also watch for the levitating magnet to fall, and make a record so you can mark at what temperature this occurs. 6. Disconnect the battery and various meters from the circuit. Your TA or TI will take your apparatus to bring the superconductor to room temperature safely. Use a hairdryer to evaporate the liquid nitrogen in the foil tray. Use the low setting and remain a safe distance away to prevent splashing. TA or TI Signature 5 of 15

6 3.1.2 Critical Temperature Analysis 1. Fill in the second column of Table 9.1a by converting the thermal coupling values to temperature using Table 9.1b. Extrapolate temperatures if your measurements are in between values on the table. 2. Use Ohm s Law to fill in column five of Table 9.1. Plot the two shaded columns as instructed in the post-lab section. 3.2 Ohm s Law A Single Resistor Connect your electronic components into the following circuit, as in Figure 9.4. Remember, the voltmeter (circled V ) does not interrupt the flow of the circuit. It is measuring a potential difference across the resistor. On the other hand, the ammeter (circled A ) is measuring current -all of the current- so it needs to interrupt the flow of the circuit. In other words, you will have one wire leave the output of power supply and go to the resistor. A wire will leave the other end of the resistor and go into the milliamp (ma) port of the ammeter. Another wire will exit the Common/Ground port of the ammeter and return to the ground of the power supply. The voltmeter will have 2 wires connected to it, one will tap into one side of the resistor, the other wire will tap into the opposite end of the resistor. Use a resistor of at least 1000 ohms. Use the color code in Section 3.3 to ensure that your resistor is 1000 ohms. 1. Raise the power supply voltage up from zero. Take readings of voltage and current at 1 Volt intervals and record them in Table If you get negative values for voltage or current, disregard the minus sign and just record positive values. 3. You should have 10 data points ranging from 1 10V. 4. Measure the resistance of R using the ohmmeter capability of the multimeter Light Bulb Power Supply Single Resistor Circuit V PS I PS + - A R Figure 9.4 V In this section you will determine whether a common light bulb obeys Ohm s Law. NOTE: IMPORTANT: CAUTION! You will use a similar circuit as in Figure 9.4 but will substitute the light bulb for the resistor and you MUST change the ammeter wires to TA or TI Signature 6 of 15

7 the highest current setting allowed. This will prevent blowing a fuse and making your time in lab so much more frustrating. Ask your TA or TI if you are unsure of what to do. The limiting rating of the light bulb is 6 volts. Keep your voltage from the power supply up to this level. Follow the same procedure as with the single resistor (Section 3.2.1). Record your current and voltage values in Table 9.3. Again, you should have 10 pairs of data points ranging from 0-6V. You may not see a linear relationship between V and I Resistors in Series: The Voltage Divider Consider the circuit shown in Figure 9.5. It is a circuit with 2 resistors in series. In electronics lingo it is called a voltage divider. You will see why this is as you measure its characteristics. Note: 1. The current through each of the resistors must be the same because the resistors are in series, i.e. I PS = I 1 = I If we add up the voltages across each resistor and the voltage of the power supply as we go around the loop, we find that they sum to zero, i.e. V PS = V 1 + V 2. This is known as the Loop Rule. 3. The resistance values of each resistor can be known by reading the color code on each. This code is included in Section 3.3. Power Supply V PS The Voltage Divider + - R I PS V 1 A I 1 Figure 9.5 I 2 R V 2 Using these facts we can derive the fraction of the power supply voltage, V PS, that appears across each of the two resistors. So for the first resistor, R 1, Procedure V 1 R = 1 Equation 9.4 V PS R 1 + R 2 1. Set up the circuit shown in Figure 9.5. You will need to include an ammeter as shown. You will also need to use the low current port of the ammeter, switching back from the high current port you used with the light bulb. You will be measuring voltages across each of the two resistors using a voltmeter. 2. Let R 1 ~ 220 ohms, and R 2 ~ 1000 ohms. 3. Set the voltage on the power supply to around 3V. Measure the voltage drops across each resistor, the current through the loop, and the actual values of each resistor. Record this information in Table 9.4 TA or TI Signature 7 of 15

8 3.2.4 Resistors in Parallel: The Current Divider The Current Divider Consider the circuit shown in Figure 9.6. It is a rearrangement of the previous circuit and puts the same 2 resistors in parallel, rather than in series. This time you have built what is called a current divider for reasons you shall verify. At the point labeled X we can apply the Current Sum Rule and write an expression like this: Power Supply V PS I PS + - R I 1 I 2 R I PS = I 1 + I 2 Equation 9.5 Next we can write Kirchoff loop rules for the left hand and right hand loops to find that, A Figure 9.6 A V PS = V 1 = V 2 Equation 9.6 We can then calculate the fraction of the current coming out of the power supply that pass through each of the resistors. For example, I 1 R = 2 Equation 9.7 I PS R 1 + R 2 Notice that now we have a current divider circuit analogous to the voltage divider except that the label of the numerator on the right hand side has switched from that of the voltage divider equation. Procedure 1. Assemble the circuit as shown in Figure 9.6. You may not have 2 ammeters as the figure shows, but the figure is trying to express that you have to measure the current in each branch. Use the same 2 resistors as before, keeping R 1 equal to 220 ohms and R 2 equal to 1000 ohms. 2. Set the power supply to about 3V. 3. Using a current meter, measure each of the three currents labeled in the figure and record the data in Table 9.5. Measure I PS directly. TA or TI Signature 8 of 15

9 3.3 Resistor Color Code The resistance value of a resistor may be read from the color code printed on its exterior. Start from the first color band that is closer to one end than the other. The first 2 color bands represent the first two digits in the value of the resistance. The third color band represents the power of ten that the two digits are multiplied by to yield the final resistance value in ohms. If there is a fourth band present, it is a measure of the tolerance of the resistor, a measure of the uncertainty in the resistor s printed value of resistance. Below you will find an example of a resistor with gray-scale representations of colors and an example of how to read the resistance value from the color code table provided. From left to right, the color order is Red Red Orange Gold. Red Red Orange Gold Figure 9.7 Looking at the Color Code table, we see that this represents the numbers 2, 2, and 10 3 or The fourth color band tells us the tolerance for this resistor is 5% (a high quality resistor). So the final resistance value is: 22 x 10 3 = 22000Ω ± 5% = 22000Ω ± 1100Ω So we would expect to measure a resistance in the range of about to ohms. Resistor Color Code Color Number Multiplier Black 0 1 Brown Red Orange Silver - Tol = 10% Gold - Tol = 5% Last Revised on January 6, 2016 TA or TI Signature 9 of 15

10 EXPERIMENT 9 Superconductivity & Ohm s Law 4. Post-Laboratory Work [20 pts] 4.1 Superconductivity [5 pts] Critical Temperature Analysis: Thermal Conductivity (mv) Temperature (deg. K) Voltage (mv) Current (A) Resistance (mω) Table 9.1a Conversion from mv to Kelvin mv Deg. K TA or TI Signature 10 of 15

11 mv Deg. K mv Deg. K mv Deg. K mv Deg. K mv Deg. K mv Deg. K Table 9.1b Take your data from Table 9.1a and make a plot of Resistance vs. Temperature (y vs. x!!) on the axes provided. Include labels and units. What is the critical temperature of the superconductor? Mark on your plot where the levitating magnet fell. TA or TI Signature 11 of 15

12 4.2 Ohm s Law [15 pts] Data Single Resistor Data R = Power Supply Setting Measured Voltage (Volts) Measured Current (Amps) Bulb Data Power Supply Setting Table 9.2 Measured Voltage (Volts) Measured Current (Amps) Series Resistor Data Power Supply Volts R 1 R 2 I PS V 1 V 2 V PS Table 9.4 Table 9.3 Parallel Resistor Data Power Supply Volts R 1 R 2 V PS I 1 I 2 I PS Table 9.5 TA or TI Signature 12 of 15

13 Ohm s Law Analysis [15 pts] Single Resistor Analysis [4 pts] 1. Take your data from Table 9.2 (Single Resistor Data) and make a plot of Voltage vs. Current (y vs. x!!) on the axes provided. Include labels and units. Is the relationship linear? If so, draw a best-fit line. (2 pts) 2. Calculate the slope of your best-fit line. Compare this value of resistance to the value labeled on the actual resistor and the value you measured from the multimeter. (1 pt) 3. Calculate the power dissipated in the resistor when V = 6.0 Volts. (1 pt) TA or TI Signature 13 of 15

14 Single Bulb Analysis [6 pts] 4. Take your data from Table 9.3 (Bulb Data) and make a plot of Voltage vs. Current on the axes provided. Include labels and units. (2 pts) 5. Is there a linear relationship between voltage and current (compared to the linearity of the single resistor)? (It should not be!) Calculate the resistance of the filament at V = 6.0 volts. (1 pt) 6. Calculate the resistance of the filament for V = 1.0 volts. (1 pt) 7. Do you think the temperature of the filament is higher at V=6.0 than at V=1.0 Volts? How does this information compare with what you learned about metal superconductors as the temperature decreases? (2 pts) TA or TI Signature 14 of 15

15 Series Resistors Analysis [2 pts] 8. Use Equation 9.4 and verify whether your measured value of V 1 is comparable to that from the equation. Show all your work. (1 pt) 9. From the value of I PS and V PS, calculate the equivalent or total resistance of the circuit. Compare this with the theoretical value. Use Equation 9.2. (1 pt) Parallel Resistors Analysis [3 pts] 10. Use Equation 9.7 and verify whether your measured value of I 1 is comparable to that from the equation. Show all of your work. (1 pt) 11. Show that the sum rule is satisfied from your measured current values using Equation 9.5. (1 pt) 12. From the value of I PS and V PS, calculate the equivalent or total resistance of the circuit. Compare this with the theoretical value. Use Equation 9.3. (1 pt) TA or TI Signature 15 of 15

Lab 3 - DC Circuits and Ohm s Law

Lab 3 DC Circuits and Ohm s Law L3-1 Name Date Partners Lab 3 - DC Circuits and Ohm s Law OBJECTIES To learn to apply the concept of potential difference (voltage) to explain the action of a battery in

EDEXCEL NATIONAL CERTIFICATE/DIPLOMA UNIT 5 - ELECTRICAL AND ELECTRONIC PRINCIPLES NQF LEVEL 3 OUTCOME 1 - D.C. CIRCUITS

EDEXCEL NATIONAL CERTIFICATE/DIPLOMA UNIT 5 - ELECTRICAL AND ELECTRONIC PRINCIPLES NQF LEVEL 3 OUTCOME - D.C. CIRCUITS Be able to use circuit theory to determine voltage, current and resistance in direct

R A _ + Figure 2: DC circuit to verify Ohm s Law. R is the resistor, A is the Ammeter, and V is the Voltmeter. A R _ +

Physics 221 Experiment 3: Simple DC Circuits and Resistors October 1, 2008 ntroduction n this experiment, we will investigate Ohm s Law, and study how resistors behave in various combinations. Along the

Series and Parallel Resistive Circuits Physics Lab VIII

Series and Parallel Resistive Circuits Physics Lab VIII Objective In the set of experiments, the theoretical expressions used to calculate the total resistance in a combination of resistors will be tested

Background: Electric resistance, R, is defined by:

RESISTANCE & OHM S LAW (PART I and II) - 8 Objectives: To understand the relationship between applied voltage and current in a resistor and to verify Ohm s Law. To understand the relationship between applied

Basic Ohm s Law & Series and Parallel Circuits

2:256 Let there be no compulsion in religion: Truth stands out clear from Error: whoever rejects evil and believes in Allah hath grasped the most trustworthy hand-hold that never breaks. And Allah heareth

very small Ohm s Law and DC Circuits Purpose: Students will become familiar with DC potentiometers circuits and Ohm s Law. Introduction: P31220 Lab

Ohm s Law and DC Circuits Purpose: Students will become familiar with DC potentiometers circuits and Ohm s Law. Introduction: Ohm s Law for electrical resistance, V = IR, states the relationship between

Resistance, Ohm s Law, and the Temperature of a Light Bulb Filament

Resistance, Ohm s Law, and the Temperature of a Light Bulb Filament Name Partner Date Introduction Carbon resistors are the kind typically used in wiring circuits. They are made from a small cylinder of

Experiment #6, Series and Parallel Circuits, Kirchhoff s Laws

Physics 182 Spring 2013 Experiment #6 1 Experiment #6, Series and Parallel Circuits, Kirchhoff s Laws 1 Purpose Our purpose is to explore and validate Kirchhoff s laws as a way to better understanding

ElectronicsLab2.nb. Electronics Lab #2. Simple Series and Parallel Circuits

Electronics Lab #2 Simple Series and Parallel Circuits The definitions of series and parallel circuits will be given in this lab. Also, measurements in very simple series and parallel circuits will be

Circuits and Resistivity

Circuits and Resistivity Look for knowledge not in books but in things themselves. W. Gilbert OBJECTIVES To learn the use of several types of electrical measuring instruments in DC circuits. To observe

Lab 3 Ohm s Law and Resistors

` Lab 3 Ohm s Law and Resistors What You Need To Know: The Physics One of the things that students have a difficult time with when they first learn about circuits is the electronics lingo. The lingo and

Experiment 3 ~ Ohm's Law, Measurement of Voltage, Current and Resistance

Experiment 3 ~ Ohm's Law, Measurement of Voltage, Current and Resistance Objective: In this experiment you will learn to use the multi-meter to measure voltage, current and resistance. Equipment: Bread

Experiment #4, Ohmic Heat

Experiment #4, Ohmic Heat 1 Purpose Physics 18 - Fall 013 - Experiment #4 1 1. To demonstrate the conversion of the electric energy into heat.. To demonstrate that the rate of heat generation in an electrical

Electrical Measurements

Electrical Measurements Experimental Objective The objective of this experiment is to become familiar with some of the electrical instruments. You will gain experience by wiring a simple electrical circuit

PHYSICS 111 LABORATORY Experiment #3 Current, Voltage and Resistance in Series and Parallel Circuits

PHYSCS 111 LABORATORY Experiment #3 Current, Voltage and Resistance in Series and Parallel Circuits This experiment is designed to investigate the relationship between current and potential in simple series

Experiment #5, Series and Parallel Circuits, Kirchhoff s Laws

Physics 182 Summer 2013 Experiment #5 1 Experiment #5, Series and Parallel Circuits, Kirchhoff s Laws 1 Purpose Our purpose is to explore and validate Kirchhoff s laws as a way to better understanding

Experiment #3, Ohm s Law

Experiment #3, Ohm s Law 1 Purpose Physics 182 - Summer 2013 - Experiment #3 1 To investigate the -oltage, -, characteristics of a carbon resistor at room temperature and at liquid nitrogen temperature,

Electrical Fundamentals Module 3: Parallel Circuits

Electrical Fundamentals Module 3: Parallel Circuits PREPARED BY IAT Curriculum Unit August 2008 Institute of Applied Technology, 2008 ATE310- Electrical Fundamentals 2 Module 3 Parallel Circuits Module

Lab 4 Series and Parallel Resistors

Lab 4 Series and Parallel Resistors What You Need To Know: (a) (b) R 3 FIGURE - Circuit diagrams. (a) and are in series. (b) and are not in series. The Physics Last week you examined how the current and

DC Circuits (Combination of resistances)

Name: Partner: Partner: Partner: DC Circuits (Combination of resistances) EQUIPMENT NEEDED: Circuits Experiment Board One Dcell Battery Wire leads Multimeter 100, 330, 1k resistors Purpose The purpose

Kirchhoff s Voltage Law and RC Circuits

Kirchhoff s oltage Law and RC Circuits Apparatus 2 1.5 batteries 2 battery holders DC Power Supply 1 multimeter 1 capacitance meter 2 voltage probes 1 long bulb and 1 round bulb 2 sockets 1 set of alligator

Lab 5 RC Circuits. What You Need To Know: Physics 226 Lab

Lab 5 R ircuits What You Need To Know: The Physics In the previous two labs you ve dealt strictly with resistors. In today s lab you ll be using a new circuit element called a capacitor. A capacitor consists

Lab E1: Introduction to Circuits

E1.1 Lab E1: Introduction to Circuits The purpose of the this lab is to introduce you to some basic instrumentation used in electrical circuits. You will learn to use a DC power supply, a digital multimeter

Experiment 4 ~ Resistors in Series & Parallel

Experiment 4 ~ Resistors in Series & Parallel Objective: In this experiment you will set up three circuits: one with resistors in series, one with resistors in parallel, and one with some of each. You

`Ohm s Law III -- Resistors in Series and Parallel

`Ohm s Law III -- esistors in Series and Parallel by Dr. ames E. Parks Department of Physics and Astronomy 40 Nielsen Physics Building he University of ennessee Knoxville, ennessee 7996-00 Copyright August,

Series and Parallel Circuits

Series and Parallel Circuits Components in a circuit can be connected in series or parallel. A series arrangement of components is where they are inline with each other, i.e. connected end-to-end. A parallel

OHM S LAW AND RESISTANCE

OHM S LAW AND RESISTANCE Resistance is one of the basic principles of Ohm s law, and can be found in virtually any device used to conduct electricity. Georg Simon Ohm was a German physicist who conducted

Circuits. PHY2049: Chapter 27 1

Circuits PHY2049: Chapter 27 1 What You Already Know Nature of current Current density Drift speed and current Ohm s law Conductivity and resistivity Calculating resistance from resistivity Power in electric

Chapter 7 Direct-Current Circuits

Chapter 7 Direct-Current Circuits 7. Introduction...7-7. Electromotive Force...7-3 7.3 Resistors in Series and in Parallel...7-5 7.4 Kirchhoff s Circuit Rules...7-7 7.5 Voltage-Current Measurements...7-9

Student Exploration: Circuits

Name: Date: Student Exploration: Circuits Vocabulary: ammeter, circuit, current, ohmmeter, Ohm s law, parallel circuit, resistance, resistor, series circuit, voltage Prior Knowledge Questions (Do these

Objectives 200 CHAPTER 4 RESISTANCE

Objectives Explain the differences among conductors, insulators, and semiconductors. Define electrical resistance. Solve problems using resistance, voltage, and current. Describe a material that obeys

People s Physics Book

The Big Ideas: The name electric current is given to the phenomenon that occurs when an electric field moves down a wire at close to the speed of light. Voltage is the electrical energy density (energy

Electrostatics. Electrostatics Version 2

1. A 150-watt lightbulb is brighter than a 60.-watt lightbulb when both are operating at a potential difference of 110 volts. Compared to the resistance of and the current drawn by the 150-watt lightbulb,

AP1 Electricity. 1. A student wearing shoes stands on a tile floor. The students shoes do not fall into the tile floor due to

1. A student wearing shoes stands on a tile floor. The students shoes do not fall into the tile floor due to (A) a force of repulsion between the shoes and the floor due to macroscopic gravitational forces.

Resistors in Series and Parallel

Resistors in Series and Parallel Bởi: OpenStaxCollege Most circuits have more than one component, called a resistor that limits the flow of charge in the circuit. A measure of this limit on charge flow

CHAPTER 17 NOTES FOR EIGHTH GRADE PHYSICAL SCIENCE ALL MATTER IS COMPOSED OF VERY SMALL PARTICLES CALLED ATOMS.

CHAPTER 17 NOTES FOR EIGHTH GRADE PHYSICAL SCIENCE ALL MATTER IS COMPOSED OF VERY SMALL PARTICLES CALLED ATOMS. THE LAW OF ELECTRIC CHARGES STAES THAT LIKE CHARGES REPEL AND OPPOSITE CHARGES ATTRACT. BECAUSE

Experiment NO.3 Series and parallel connection

Experiment NO.3 Series and parallel connection Object To study the properties of series and parallel connection. Apparatus 1. DC circuit training system 2. Set of wires. 3. DC Power supply 4. Digital A.V.O.

The Electrical Properties of Materials: Resistivity

The Electrical Properties of Materials: Resistivity 1 Objectives 1. To understand the properties of resistance and resistivity in conductors, 2. To measure the resistivity and temperature coefficient of

Note-A-Rific: Characteristics

Note-A-Rific: Characteristics Any path along which electrons can flow is a circuit. For a continuous flow of electrons, there must be a complete circuit with no gaps. A gap is usually an electric switch

How Does it Flow? Electricity, Circuits, and Motors

How Does it Flow? Electricity, Circuits, and Motors Introduction In this lab, we will investigate the behavior of some direct current (DC) electrical circuits. These circuits are the same ones that move

Measuring Electric Phenomena: the Ammeter and Voltmeter

Measuring Electric Phenomena: the Ammeter and Voltmeter 1 Objectives 1. To understand the use and operation of the Ammeter and Voltmeter in a simple direct current circuit, and 2. To verify Ohm s Law for

Activity 1: Light Emitting Diodes (LEDs)

Activity 1: Light Emitting Diodes (LEDs) Time Required: 45 minutes Materials List Group Size: 2 Each pair needs: One each of the following: One Activity 1 bag containing: o Red LED o Yellow LED o Green

Ohm's Law and Circuits

2. Conductance, Insulators and Resistance A. A conductor in electricity is a material that allows electrons to flow through it easily. Metals, in general, are good conductors. Why? The property of conductance

How do you measure voltage and current in electric circuits? Materials

20A Electricity How do you measure voltage and current in electric circuits? Electricity Investigation 20A We use electricity every day, nearly every minute! In this Investigation you will build circuits

Chapter 11- Electricity

Chapter 11- Electricity Course Content Definition of Electricity Circuit Diagrams Series and Parallel Circuits Calculating total resistances Measurement of Electricity Ammeters and Voltmeters Ohm s Law

Lab #2: Parallel and Series Resistors

Fall 2013 EELE 250 Circuits, Devices, and Motors Lab #2: Parallel and Series Resistors Scope: Use a multimeter to measure resistance, DC voltage, and current Use the color code for resistors. Use the prototype-board

Resistors in Series and Parallel Circuits

69 Resistors in Series and Parallel Circuits E&M: Series and parallel circuits Equipment List DataStudio file: Not Required Qty s Part Numbers 1 C/DC Electronics Lab EM-8656 2 D cell 1.5 volt Introduction

Lab 5: Simple Electrical Circuits

Lab 5: Simple Electrical Circuits Introduction: In this laboratory you will explore simple DC (direct current) electrical circuits. The primary goal of the lab will be to develop a model for electricity.

CHAPTER 19: DC Circuits. Answers to Questions

HAPT 9: D ircuits Answers to Questions. The birds are safe because they are not grounded. Both of their legs are essentially at the same voltage (the only difference being due to the small resistance of

EXPERIMENT 7 OHM S LAW, RESISTORS IN SERIES AND PARALLEL

260 7- I. THEOY EXPEIMENT 7 OHM S LAW, ESISTOS IN SEIES AND PAALLEL The purposes of this experiment are to test Ohm's Law, to study resistors in series and parallel, and to learn the correct use of ammeters

TOPIC 3.1: ELECTRIC CIRCUITS

TOPIC 3.1: ELECTRIC CIRCUITS S4P-3-1 S4P-3-2 S4P-3-3 S4P-3-4 S4P-3-5 S4P-3-6 Describe the origin of conventional current and relate its direction to the electron flow in a conductor. Describe the historical

Lab 2: Resistance, Current, and Voltage

2 Lab 2: Resistance, Current, and Voltage I. Before you come to la.. A. Read the following chapters from the text (Giancoli): 1. Chapter 25, sections 1, 2, 3, 5 2. Chapter 26, sections 1, 2, 3 B. Read

Electricity Review-Sheet

Name: ate: 1. The unit of electrical charge in the MKS system is the. volt. ampere. coulomb. mho 2. Which sketch best represents the charge distribution around a neutral electroscope when a positively

PS-6.2 Explain the factors that determine potential and kinetic energy and the transformation of one to the other.

PS-6.1 Explain how the law of conservation of energy applies to the transformation of various forms of energy (including mechanical energy, electrical energy, chemical energy, light energy, sound energy,

Lab 11: Magnetic Fields Name:

Lab 11: Magnetic Fields Name: Group Members: Date: TA s Name: Objectives: To measure and understand the magnetic field of a bar magnet. To measure and understand the magnetic field of an electromagnet,

Current Electricity Lab Series/Parallel Circuits. Safety and Equipment Precautions!

Current Electricity Lab Series/Parallel Circuits Name Safety and Equipment Precautions! Plug in your power supply and use ONLY the D.C. terminals of the power source, NOT the A. C. terminals. DO NOT touch

Experiment: Series and Parallel Circuits

Phy203: General Physics Lab page 1 of 6 Experiment: Series and Parallel Circuits OBJECTVES MATERALS To study current flow and voltages in series and parallel circuits. To use Ohm s law to calculate equivalent

Pre-Lab 7 Assignment: Capacitors and RC Circuits

Name: Lab Partners: Date: Pre-Lab 7 Assignment: Capacitors and RC Circuits (Due at the beginning of lab) Directions: Read over the Lab Handout and then answer the following questions about the procedures.

THERMOCOUPLE THEORY. Positive leg. (Joined End) Negative leg. Certain combinations of metals must be used to make up the thermocouple pairs.

WHAT IS A THERMOCOUPLE? In 1821, Thomas Seebeck discovered if metals of two different materials were joined at both ends and one end was at a different temperature than the other, a current was created.

Science AS90191 Describe Aspects of Physics.

Circuits and components Science AS90191 Describe Aspects of Physics. An electric current is the movement of electrons (negatively charged particles). A circuit is made up of components connected together

7. What is the current in a circuit if 15 coulombs of electric charge move past a given point in 3 seconds? (1) 5 A (3) 18 A (2) 12 A (4) 45 A

1. Compared to the number of free electrons in a conductor, the number of free electrons in an insulator of the same volume is less the same greater 2. Most metals are good electrical conductors because

BUILDING A BASIC CIRCUIT

Teacher Information BUILDING A BASIC CIRCUIT NSES9-12.2 Physical Science: Interactions of Energy and Matter Adaptations Some adaptations and modifications that may assist a student with visual and/or other

LAB2 Resistors, Simple Resistive Circuits in Series and Parallel Objective:

LAB2 Resistors, Simple Resistive Circuits in Series and Parallel Objective: In this lab, you will become familiar with resistors and potentiometers and will learn how to measure resistance. You will also

Student Content Brief Advanced Level Electric Circuits Background Information There are a variety of forces acting on the body of the Sea Perch. One important force is pushing electrons through the wires

Experiment A5. Hysteresis in Magnetic Materials

HYSTERESIS IN MAGNETIC MATERIALS A5 1 Experiment A5. Hysteresis in Magnetic Materials Objectives This experiment illustrates energy losses in a transformer by using hysteresis curves. The difference betwen

Lab 1: DC Circuits. Student 1, student1@ufl.edu Partner : Student 2, student2@ufl.edu

Lab Date Lab 1: DC Circuits Student 1, student1@ufl.edu Partner : Student 2, student2@ufl.edu I. Introduction The purpose of this lab is to allow the students to become comfortable with the use of lab

GENERAL SCIENCE LABORATORY 1110L Lab Experiment 6: Ohm s Law

GENERAL SCIENCE LABORATORY 1110L Lab Experiment 6: Ohm s Law OBJECTIVES: To verify Ohm s law, the mathematical relationship among current, voltage or potential difference, and resistance, in a simple circuit.

Capacitance. Apparatus: RC (Resistor-Capacitor) circuit box, voltmeter, power supply, cables

apacitance Objective: To observe the behavior of a capacitor charging and discharging through a resistor; to determine the effective capacitance when capacitors are connected in series or parallel. Apparatus:

CALIBRATION OF A THERMISTOR THERMOMETER

CALIBRATION OF A THERMISTOR THERMOMETER 1 I. Introduction Calibration experiments or procedures are fairly common in laboratory work that involves any type of instrumentation. Calibration procedures always

Chapter 13: Electric Circuits

Chapter 13: Electric Circuits 1. A household circuit rated at 120 Volts is protected by a fuse rated at 15 amps. What is the maximum number of 100 watt light bulbs which can be lit simultaneously in parallel

MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question.

MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 1) If the voltage at a point in space is zero, then the electric field must be A) zero. B) positive.

= (0.400 A) (4.80 V) = 1.92 W = (0.400 A) (7.20 V) = 2.88 W

Physics 2220 Module 06 Homework 0. What are the magnitude and direction of the current in the 8 Ω resister in the figure? Assume the current is moving clockwise. Then use Kirchhoff's second rule: 3.00

Lab 9: Energy Conservation in Circuits & Charge on a Capacitor

Part (1) Energy Conservation in Circuits OBJECTIVES In this part of the lab you will Write the energy conservation equation (loop rule) for several pairs of circuits Predict the relation between the currents

Unit: Charge Differentiated Task Light it Up!

The following instructional plan is part of a GaDOE collection of Unit Frameworks, Performance Tasks, examples of Student Work, and Teacher Commentary. Many more GaDOE approved instructional plans are

Resistors in Series and Parallel

OpenStax-CNX module: m42356 1 Resistors in Series and Parallel OpenStax College This work is produced by OpenStax-CNX and licensed under the Creative Commons Attribution License 3.0 Abstract Draw a circuit

The Time Constant of an RC Circuit

The Time Constant of an RC Circuit 1 Objectives 1. To determine the time constant of an RC Circuit, and 2. To determine the capacitance of an unknown capacitor. 2 Introduction What the heck is a capacitor?

EE 1202 Experiment #2 Resistor Circuits

EE 1202 Experiment #2 Resistor Circuits 1. ntroduction and Goals: Demonstrates the voltage-current relationships in DC and AC resistor circuits. Providing experience in using DC power supply, digital multimeter,

A MODEL OF VOLTAGE IN A RESISTOR CIRCUIT AND AN RC CIRCUIT

A MODEL OF VOLTAGE IN A RESISTOR CIRCUIT AND AN RC CIRCUIT ARJUN MOORJANI, DANIEL STRAUS, JENNIFER ZELENTY Abstract. We describe and model the workings of two simple electrical circuits. The circuits modeled

Two kinds of electrical charges

ELECTRICITY NOTES Two kinds of electrical charges Positive charge Negative charge Electrons are negatively charged Protons are positively charged The forces from positive charges are canceled by forces

Lab 5 RC Circuits: Charge Changing in Time Observing the way capacitors in RC circuits charge and discharge.

Print Your Name Lab 5 RC Circuits: Charge Changing in Time Observing the way capacitors in RC circuits charge and discharge. Print Your Partners' Names Instructions October 15, 2015October 13, 2015 Read

Experiment 9 ~ RC Circuits

Experiment 9 ~ RC Circuits Objective: This experiment will introduce you to the properties of circuits that contain both resistors AND capacitors. Equipment: 18 volt power supply, two capacitors (8 µf

Series and Parallel Circuits

Series and Parallel Circuits Direct-Current Series Circuits A series circuit is a circuit in which the components are connected in a line, one after the other, like railroad cars on a single track. There

STUDY MATERIAL FOR CLASS 10+2 - Physics- CURRENT ELECTRICITY. The flow of electric charges in a particular direction constitutes electric current.

Chapter : 3 Current Electricity Current Electricity The branch of Physics which deals with the study of electric charges in motion is called current electricity. Electric current The flow of electric charges

EXPERIMENTS with PHOTOVOLTAIC CELLS

EXPERIMENTS with PHOTOVOLTAIC CELLS for high school science students By Dick Erickson Pleasant Hill High School derickso@lane.k12.or.us Frank Vignola University of Oregon fev@uoregon.edu For Emerald People

Lab #2: Non-Ideal Sources and Renewable Energy Sources

Lab #2: Non-Ideal Sources and Renewable Energy Sources Theory & Introduction Goals for Lab #2 The goals for this lab are to introduce you to the limitations of real power sources and compare them to the

Kirchhoff's Rules and Applying Them

[ Assignment View ] [ Eðlisfræði 2, vor 2007 26. DC Circuits Assignment is due at 2:00am on Wednesday, February 21, 2007 Credit for problems submitted late will decrease to 0% after the deadline has passed.

8.2. Electric Current. Did You Know? 8-2A. Lighting It Up. Words to Know. Find Out ACTIVITY. Safety. Materials. What Did You Find Out?

8.2 Electric Current Current electricity is the flow of charged particles in a complete circuit. The unit for measuring electric current is the ampere (A), which is defined as one coulomb of charge passing

1) ASSOCIATE ELEMENTARY PARTICLES WITH THEIR ELECTRICAL CHARGE

Name Date STUDY GUIDE CHAPTER 5 ELECTRICITY AND MAGNETISM 1) ASSOCIATE ELEMENTARY PARTICLES WITH THEIR ELECTRICAL CHARGE Scientists now know that an atom is composed of even smaller particles of matter:

Physics 3330 Experiment #2 Fall 1999. DC techniques, dividers, and bridges R 2 =(1-S)R P R 1 =SR P. R P =10kΩ 10-turn pot.

Physics 3330 Experiment #2 Fall 1999 DC techniques, dividers, and bridges Purpose You will gain a familiarity with the circuit board and work with a variety of DC techniques, including voltage dividers,

Physics 221 Experiment 5: Magnetic Fields

Physics 221 Experiment 5: Magnetic Fields August 25, 2007 ntroduction This experiment will examine the properties of magnetic fields. Magnetic fields can be created in a variety of ways, and are also found

Maximum value. resistance. 1. Connect the Current Probe to Channel 1 and the Differential Voltage Probe to Channel 2 of the interface.

Series and Parallel Circuits Computer 23 Components in an electrical circuit are in series when they are connected one after the other, so that the same current flows through both of them. Components are

Tristan s Guide to: Solving Series Circuits. Version: 1.0 Written in 2006. Written By: Tristan Miller Tristan@CatherineNorth.com

Tristan s Guide to: Solving Series Circuits. Version: 1.0 Written in 2006 Written By: Tristan Miller Tristan@CatherineNorth.com Series Circuits. A Series circuit, in my opinion, is the simplest circuit

Chapter 17 Study Questions Name: Class:

Chapter 17 Study Questions Name: Class: Multiple Choice Identify the letter of the choice that best completes the statement or answers the question. 1. If two charges repel each other, the two charges

Kirchhoff s Laws Physics Lab IX

Kirchhoff s Laws Physics Lab IX Objective In the set of experiments, the theoretical relationships between the voltages and the currents in circuits containing several batteries and resistors in a network,

STUDY GUIDE: ELECTRICITY AND MAGNETISM

319 S. Naperville Road Wheaton, IL 60187 www.questionsgalore.net Phone: (630) 580-5735 E-Mail: info@questionsgalore.net Fax: (630) 580-5765 STUDY GUIDE: ELECTRICITY AND MAGNETISM An atom is made of three

Question Bank. Electric Circuits, Resistance and Ohm s Law

Electric Circuits, Resistance and Ohm s Law. Define the term current and state its SI unit. Ans. The rate of flow of charge in an electric circuit is called current. Its SI unit is ampere. 2. (a) Define