# Electron Charge to Mass Ratio e/m

Save this PDF as:

Size: px
Start display at page:

## Transcription

1 Electron Charge to Mass Ratio e/m J. Lukens, B. Reid, A. Tuggle PH , Group 4 18 January 010 Abstract We have repeated with some modifications an 1897 experiment by J. J. Thompson investigating the cyclotronic motion of an electron beam. From the empirical data obtained, we arrive at a value for the ratio of charge to mass of an electron comparable to that commonly accepted. Contents 1 Introduction 1.1 Purpose and Description of Experiment Theory Procedure 3 Observations Data Uncertainty Calculations Uncertainty Analysis Concluding Discussion 6 1

2 1 Introduction 1.1 Purpose and Description of Experiment In an evacuated glass chamber (back-filled with low-pressure helium gas), electrons thermionically emmitted from a heated metal filament are accelerated through a potential difference. The cyclotronic motion of the resulting electron beam due to an applied magnetic field (from a Helmholtz coil apparatus) is investigated to determine the ratio of the electrons charge to their mass. Assuming the filament temperature to be around 4000 K, we can expect the electrons to be emitted with an average energy similar to the energy level of atoms in a gas at the same temperature, 1 i.e. 3 k BT 0.5 ev. This energy is small compared to the 300 to 500 ev imparted by the accelerating potential, so we approximate the electrons as being emitted with no kinetic energy. Using a common calculation for the mean free path l in a gas (molecular diamter d) at low pressure P, l = k B T ( πd P ) 1, given that the pressure in the glass chamber is 1.3 Pa we find that the mean free path of the electrons is on the order of 10 cm, comparable to the circumference of the path described, so we may treat the electrons as if in vacuum. 1. Theory A Helmholtz coil apparatus was used to produce an essentially uniform magnetic field perpendicular to the path of the electrons. Griffiths 3 gives the magnetic field B near the center of the coils as B = 8µ 0I 5 5a where µ 0 is the magnetic constant, I is the current through the coil wires, and a is the coil radius. This makes sense, as a smaller radius and larger current would serve to increase the field, as expected. At the low pressures of gas used in the experiment the magnetic permeability does not deviate appreciably from that of vacuum. The advantage of this particular geometry is that the second derivative of the magnetic field vanishes at the midpoint between the two coils, producing a field strength reliably uniform near the midpoint. Now the magnetic force on the electron is proportional to its velocity, which, after acceleration is on the order of 10 7 m/s. Using the relation that r = vm eb (here, v, m, and e are the electron s velocity, mass, and charge respectively, and r is, of course, the path radius), we note that a magnetic field on the order of 1 mt will produce a path of about 5 cm, corresponding roughly to the size of the glass chamber. Luckily, that is precisely the regime of the Helmholtz coils employed. Procedure The experiment began by connecting the power supplies to their appropriate components. A 6 V AC supply was connected to the heater filament to warm the cathode for

3 thermionic electron emission. Another supply established a potential between the anode and cathode of the electron gun, providing the accelerating voltage V acc used to impart emitted electrons with kinetic energy. A third source was connected to the Helmholtz coils, yielding a current and producing the required magnetic field. As the cathode heated, the voltage of the Helmholtz coils was adjusted to establish a current in them of about 1.95 A. When the electron beam had grown strong enough for experimental work, the accelerating voltage V acc was tweaked until a circular electron path with an approximate radius of 5 cm arose; this occured at a voltage of about 300 V. As recommended, 4 we determined to work with as high an accelerating voltage as possible, so V acc was set to 35 V, and the measurements began. One group member sat down in front of the electron tube, and aligning his dominant eye such that the beam exactly covered its reflection he averaged the two radius measurements and recorded the value. We then increased the accelerating potential to 350 V, and another experimenter repeated the above procedure, measuring the new radius. This process continued for each successive value of V acc. Thereafter, the current through the Helmholtz coil was lowered to 1.86 A, and utilizing the same accelerating voltages as before, we logged the electron path radius at each potential. The system was then reconfigured by connecting a DC supply to the deflection plates. Maintaining an accelerating voltage of about 50 V, we varied the potential difference of the deflection plates from 0 to 50 V. As this value increased, the electron beam curved progressively upward, which was as expected, for the negatively charged electrons should experience a net force toward the positively charged upper plate. After turning off the equipment, the calculations described below yielded values for the desired ratio e/m. 3 Observations 3.1 Data Table 1: Measurements for I = 1.95 A V acc r [m] e/m [ C/kg] σ [ C/kg]

4 e/m (A-s/kg ) e/m values at 1.95 A 1.9 accepted value V acc Table : Measurements for I = 1.86 A V acc r [m] e/m [ C/kg] σ [ C/kg]

5 e/m (A-s/kg ) e/m values at 1.86 A accepted value V acc 3. Uncertainty Calculations The equation ) 3 a e/m = V acc ( 4 5 (Nµ 0 Ir) was used as the calculation, taking N = 130, a = 0.15 m, I = 1.95 A and (as explained below) V acc and r being the experimentally measured values. Uncertainty was calculated using standard techniques 5 taking δq q = ( δi I ) ( + δr ) + r ( ) δvacc, where q is the charge-to-mass quotient. The final values were calculated using a weighted average, where each value was weighted in proportion to δ, where δ is the uncertainty in each measurement, and the final uncertainty δ wav was calculated as δ wav = 1 ( ). δ i The final tabulation yielded a weighted average value of 1.55± C/kg. 5 V acc

6 3.3 Uncertainty Analysis There were a number of causes of uncertainty in this experiment. Some were purely based on the equipment. The V acc was only measured to within one volt, so an uncertainty of ±0.5 V was assigned for this measurement. The current varied over the course of the experiment, starting at 1.97 A and dropping to 1.94 A, so a measurement of 1.95±0.03 A was given for the first trial. For the second trial, the current is measured as 1.86±0.03 A. The second trial took far less time (thus, less time for variation in current supplied to the Helmholtz coils) but the current was only measured at the beginning, so the same uncertainty has been left for any rounding in the apparatus and any potential fluctuation that was not observed. Numerous sources of uncertainty were associated with measuring the radius. For instance, the equations are based on the assumption that the electrons are placed in a vacuum, which is not strictly true, as the chamber had been backfilled with helium. This would decrease the actual velocity of the electrons below the theoretical level, since they may collide with other particles. Much uncertainty was associated with physically measuring the radius. The ruler that had been placed on the apparatus was not always in line with the diameter of the electron circle; often it was aligned with somewhere in the upper half of the circle, requiring the experimenters to eyeball the actual diameter. Measurement also became less precise as the radius of the circle increased and the electron path approached the edge of the containing bulb. The bulb being spherical, the rapidly changing thickness of glass through which the light passed muddled the path s sharpness. Consequently, measurements at higher voltages (larger radii) are potentially less reliable. Also, another source of uncertainty was the fact that three different observers were used in this experiment; they may have employed slightly different estimation techniques, allowing the possibility of slightly inconsistent measuring. The uncertainty given for the estimation of the radius was ±0. cm. Finally, the magnetic field of the earth introduces some uncertainty in the experiment. However, Earth s magnetic field has a strength of roughly 50 µt at this location on the earth, 6 while the field produced by the experiment has a strength on the order of mt. Moreover, the Helmholtz field was aligned very nearly east-to-west, so that the largest component of the Earth s field was parallel to the electron velocities, further diminshing its effect on measurements. Clearly, therefore, the influence of the earth s field is quite small compared to other uncertainties and can be justifiably ignored in all calculations. Moreover, relativistic effects may play a role at higher accelerating voltages (i.e. higher electron speeds) (>10 kv 7 ), but are ignored for the voltage levels used in this experiment (<500 V). 4 Concluding Discussion Admittedly, the calculated values of the electron s charge-to-mass ratio e/m diverge appreciably from the accepted value. At both Helmholtz currents, the uncertainties in e/m fail to capture the established value of C/kg. Such deviation implies the presence of serious systematic error. Therefore the experimental measurements namely, the accelerating voltage, Helmholtz current, and electron path radius all would require closer examination in future experiments. The voltmeter and ammeter used in this laboratory 6

### LAB 8: Electron Charge-to-Mass Ratio

Name Date Partner(s) OBJECTIVES LAB 8: Electron Charge-to-Mass Ratio To understand how electric and magnetic fields impact an electron beam To experimentally determine the electron charge-to-mass ratio.

### Measurement of Charge-to-Mass (e/m) Ratio for the Electron

Measurement of Charge-to-Mass (e/m) Ratio for the Electron Experiment objectives: measure the ratio of the electron charge-to-mass ratio e/m by studying the electron trajectories in a uniform magnetic

### E/M Experiment: Electrons in a Magnetic Field.

E/M Experiment: Electrons in a Magnetic Field. PRE-LAB You will be doing this experiment before we cover the relevant material in class. But there are only two fundamental concepts that you need to understand.

### CHARGE TO MASS RATIO OF THE ELECTRON

CHARGE TO MASS RATIO OF THE ELECTRON In solving many physics problems, it is necessary to use the value of one or more physical constants. Examples are the velocity of light, c, and mass of the electron,

### Modern Physics Laboratory e/m with Teltron Deflection Tube

Modern Physics Laboratory e/m with Teltron Deflection Tube Josh Diamond & John Cummings Fall 2010 Abstract The deflection of an electron beam by electric and magnetic fields is observed, and the charge

### Date: Deflection of an Electron in a Magnetic Field

Name: Partners: Date: Deflection of an Electron in a Magnetic Field Purpose In this lab, we use a Cathode Ray Tube (CRT) to measure the effects of an electric and magnetic field on the motion of a charged

### J. J. Thomson's Measurement of e/m for the electron

Physics 165 Laboratory J. J. Thomson's Measurement of e/m for the electron In 1897, the cathode ray tube or CRT, which is now a part of most TV sets, was the last word in advanced laboratory instrumentation

### Charge and Mass of the Electron

PHY 19 Charge and Mass of the Electron 1 Charge and Mass of the Electron Motivation for the Experiment The aim of this experiment is to measure the charge and mass of the electron. The charge will be measured

### Motion of Charges in Combined Electric and Magnetic Fields; Measurement of the Ratio of the Electron Charge to the Electron Mass

Motion of Charges in Combined Electric and Magnetic Fields; Measurement of the Ratio of the Electron Charge to the Electron Mass Object: Understand the laws of force from electric and magnetic fields.

### Electron Charge to Mass Ratio Matthew Norton, Chris Bush, Brian Atinaja, Becker Steven. Norton 0

Electron Charge to Mass Ratio Matthew Norton, Chris Bush, Brian Atinaja, Becker Steven Norton 0 Norton 1 Abstract The electron charge to mass ratio was an experiment that was used to calculate the ratio

### Lab 4: Magnetic Force on Electrons

Lab 4: Magnetic Force on Electrons Introduction: Forces on particles are not limited to gravity and electricity. Magnetic forces also exist. This magnetic force is known as the Lorentz force and it is

### Homework #8 203-1-1721 Physics 2 for Students of Mechanical Engineering. Part A

Homework #8 203-1-1721 Physics 2 for Students of Mechanical Engineering Part A 1. Four particles follow the paths shown in Fig. 32-33 below as they pass through the magnetic field there. What can one conclude

### 1. Units of a magnetic field might be: A. C m/s B. C s/m C. C/kg D. kg/c s E. N/C m ans: D

Chapter 28: MAGNETIC FIELDS 1 Units of a magnetic field might be: A C m/s B C s/m C C/kg D kg/c s E N/C m 2 In the formula F = q v B: A F must be perpendicular to v but not necessarily to B B F must be

### 6/2016 E&M forces-1/8 ELECTRIC AND MAGNETIC FORCES. PURPOSE: To study the deflection of a beam of electrons by electric and magnetic fields.

6/016 E&M forces-1/8 ELECTRIC AND MAGNETIC FORCES PURPOSE: To study the deflection of a beam of electrons by electric and magnetic fields. APPARATUS: Electron beam tube, stand with coils, power supply,

### Magnetism. d. gives the direction of the force on a charge moving in a magnetic field. b. results in negative charges moving. clockwise.

Magnetism 1. An electron which moves with a speed of 3.0 10 4 m/s parallel to a uniform magnetic field of 0.40 T experiences a force of what magnitude? (e = 1.6 10 19 C) a. 4.8 10 14 N c. 2.2 10 24 N b.

### Exam 2 Solutions. PHY2054 Spring Prof. P. Kumar Prof. P. Avery March 5, 2008

Prof. P. Kumar Prof. P. Avery March 5, 008 Exam Solutions 1. Two cylindrical resistors are made of the same material and have the same resistance. The resistors, R 1 and R, have different radii, r 1 and

### Deflection of Electrons in an Electric Field

Name: Partners: Date: Deflection of Electrons in an Electric Field Purpose In this lab, we use a Cathode Ray Tube (CRT) to measure the effects of an electric field on the motion of a charged particle,

### CHARGED PARTICLES & MAGNETIC FIELDS - WebAssign

Name: Period: Due Date: Lab Partners: CHARGED PARTICLES & MAGNETIC FIELDS - WebAssign Purpose: Use the CP program from Vernier to simulate the motion of charged particles in Magnetic and Electric Fields

### Fall 12 PHY 122 Homework Solutions #8

Fall 12 PHY 122 Homework Solutions #8 Chapter 27 Problem 22 An electron moves with velocity v= (7.0i - 6.0j)10 4 m/s in a magnetic field B= (-0.80i + 0.60j)T. Determine the magnitude and direction of the

### Millikan Oil Drop Experiment Matthew Norton, Jurasits Christopher, Heyduck William, Nick Chumbley. Norton 0

Millikan Oil Drop Experiment Matthew Norton, Jurasits Christopher, Heyduck William, Nick Chumbley Norton 0 Norton 1 Abstract The charge of an electron can be experimentally measured by observing an oil

### Review Questions PHYS 2426 Exam 2

Review Questions PHYS 2426 Exam 2 1. If 4.7 x 10 16 electrons pass a particular point in a wire every second, what is the current in the wire? A) 4.7 ma B) 7.5 A C) 2.9 A D) 7.5 ma E) 0.29 A Ans: D 2.

### Conceptual: 1, 3, 5, 6, 8, 16, 18, 19. Problems: 4, 6, 8, 11, 16, 20, 23, 27, 34, 41, 45, 56, 60, 65. Conceptual Questions

Conceptual: 1, 3, 5, 6, 8, 16, 18, 19 Problems: 4, 6, 8, 11, 16, 20, 23, 27, 34, 41, 45, 56, 60, 65 Conceptual Questions 1. The magnetic field cannot be described as the magnetic force per unit charge

### Chapter 22 Magnetism

22.6 Electric Current, Magnetic Fields, and Ampere s Law Chapter 22 Magnetism 22.1 The Magnetic Field 22.2 The Magnetic Force on Moving Charges 22.3 The Motion of Charged particles in a Magnetic Field

### Charged Particle in a Magnetic Field

Charged Particle in a Magnetic Field Consider a particle moving in an external magnetic field with its velocity perpendicular to the field The force is always directed toward the center of the circular

### Vacuum Evaporation Recap

Sputtering Vacuum Evaporation Recap Use high temperatures at high vacuum to evaporate (eject) atoms or molecules off a material surface. Use ballistic flow to transport them to a substrate and deposit.

### J.J. Thomson, Cathode Rays and the Electron

Introduction Voltage source Experimenters had noticed that sparks travel through rarefied (i.e. low pressure) air since the time of Franklin. The basic setup was to have two metal plates inside a glass

### Force on Moving Charges in a Magnetic Field

[ Assignment View ] [ Eðlisfræði 2, vor 2007 27. Magnetic Field and Magnetic Forces Assignment is due at 2:00am on Wednesday, February 28, 2007 Credit for problems submitted late will decrease to 0% after

### 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

### Magnetic Fields and Forces. AP Physics B

Magnetic ields and orces AP Physics acts about Magnetism Magnets have 2 poles (north and south) Like poles repel Unlike poles attract Magnets create a MAGNETIC IELD around them Magnetic ield A bar magnet

### Physics 30 Worksheet #10 : Magnetism From Electricity

Physics 30 Worksheet #10 : Magnetism From Electricity 1. Draw the magnetic field surrounding the wire showing electron current below. x 2. Draw the magnetic field surrounding the wire showing electron

### Physics Spring Experiment #8 1 Experiment #8, Magnetic Forces Using the Current Balance

Physics 182 - Spring 2012 - Experiment #8 1 Experiment #8, Magnetic Forces Using the Current Balance 1 Purpose 1. To demonstrate and measure the magnetic forces between current carrying wires. 2. To verify

### ) 0.7 =1.58 10 2 N m.

Exam 2 Solutions Prof. Paul Avery Prof. Andrey Korytov Oct. 29, 2014 1. A loop of wire carrying a current of 2.0 A is in the shape of a right triangle with two equal sides, each with length L = 15 cm as

### Physics 42 Lab 4 Fall 2012 Cathode Ray Tube (CRT)

Physics 42 Lab 4 Fall 202 Cathode Ray Tube (CRT) PRE-LAB Read the background information in the lab below and then derive this formula for the deflection. D = LPV defl 2 SV accel () Redraw the diagram

### PY106 Class13. Permanent Magnets. Magnetic Fields and Forces on Moving Charges. Interactions between magnetic north and south poles.

Permanent Magnets Magnetic ields and orces on Moing Charges 1 We encounter magnetic fields frequently in daily life from those due to a permanent magnet. Each permanent magnet has a north pole and a south

### 1. The diagram below represents magnetic lines of force within a region of space.

1. The diagram below represents magnetic lines of force within a region of space. 4. In which diagram below is the magnetic flux density at point P greatest? (1) (3) (2) (4) The magnetic field is strongest

### Chapter 14 Magnets and

Chapter 14 Magnets and Electromagnetism How do magnets work? What is the Earth s magnetic field? Is the magnetic force similar to the electrostatic force? Magnets and the Magnetic Force! We are generally

### MAGNETIC FORCE ON AN ELECTRIC CHARGE

DO PHYSICS ONLINE MOTORS AND GENERATORS MAGNETIC ORCE ON AN ELECTRIC CHARGE Experiments show that moing electric charges are deflected in magnetic fields. Hence, moing electric charges experience forces

### Physics 41, Winter 1998 Lab 1 - The Current Balance. Theory

Physics 41, Winter 1998 Lab 1 - The Current Balance Theory Consider a point at a perpendicular distance d from a long straight wire carrying a current I as shown in figure 1. If the wire is very long compared

### Physics 1653 Exam 3 - Review Questions

Physics 1653 Exam 3 - Review Questions 3.0 Two uncharged conducting spheres, A and B, are suspended from insulating threads so that they touch each other. While a negatively charged rod is held near, but

### Cathode Ray Tube. Introduction. Functional principle

Introduction The Cathode Ray Tube or Braun s Tube was invented by the German physicist Karl Ferdinand Braun in 897 and is today used in computer monitors, TV sets and oscilloscope tubes. The path of the

### A satellite of mass 5.00x10² kg is in a circular orbit of radius 2r around Earth. Then it is moved to a circular orbit radius of 3r.

Supplemental Questions A satellite of mass 5.00x10² kg is in a circular orbit of radius 2r around Earth. Then it is moved to a circular orbit radius of 3r. (a) Determine the satellite s GPE in orbit. (b)

### Radiation Interactions with Matter: Energy Deposition

Radiation Interactions with Matter: Energy Deposition Biological effects are the end product of a long series of phenomena, set in motion by the passage of radiation through the medium. Image removed due

### Physics 9 Fall 2009 Homework 7 - Solutions

Physics 9 Fall 009 Homework 7 - s 1. Chapter 33 - Exercise 10. At what distance on the axis of a current loop is the magnetic field half the strength of the field at the center of the loop? Give your answer

### UNIVERSITY OF SASKATCHEWAN Department of Physics and Engineering Physics

UNIVERSITY OF SASKATCHEWAN Department of Physics and Engineering Physics Physics 111.6 MIDTERM TEST #4 March 15, 2007 Time: 90 minutes NAME: (Last) Please Print (Given) STUDENT NO.: LECTURE SECTION (please

### Magnetic Field and Magnetic Forces

Chapter 27 Magnetic Field and Magnetic Forces PowerPoint Lectures for University Physics, Thirteenth Edition Hugh D. Young and Roger A. Freedman Lectures by Wayne Anderson Goals for Chapter 27 Magnets

### Transmission through the quadrupole mass spectrometer mass filter: The effect of aperture and harmonics

Transmission through the quadrupole mass spectrometer mass filter: The effect of aperture and harmonics A. C. C. Voo, R. Ng, a) J. J. Tunstall, b) and S. Taylor Department of Electrical and Electronic

### Chapter 19 Magnetic Forces and Fields

Chapter 19 Magnetic Forces and Fields Student: 3. The magnetism of the Earth acts approximately as if it originates from a huge bar magnet within the Earth. Which of the following statements are true?

### Chapter 21. Magnetic Forces and Magnetic Fields

Chapter 21 Magnetic Forces and Magnetic Fields 21.1 Magnetic Fields The needle of a compass is permanent magnet that has a north magnetic pole (N) at one end and a south magnetic pole (S) at the other.

### ELECTRIC FIELD LINES AND EQUIPOTENTIAL SURFACES

ELECTRIC FIELD LINES AND EQUIPOTENTIAL SURFACES The purpose of this lab session is to experimentally investigate the relation between electric field lines of force and equipotential surfaces in two dimensions.

### Profs. A. Petkova, A. Rinzler, S. Hershfield. Exam 2 Solution

PHY2049 Fall 2009 Profs. A. Petkova, A. Rinzler, S. Hershfield Exam 2 Solution 1. Three capacitor networks labeled A, B & C are shown in the figure with the individual capacitor values labeled (all units

### The Electric Force. From mechanics, the relationship for the gravitational force on an object is: m is the mass of the particle of interest,

. The Electric Force Concepts and Principles The Gravitational Analogy In introducing the concept of the electric field, I tried to illustrate it by drawing an analogy with the gravitational field, g.

### TOF FUNDAMENTALS TUTORIAL

TOF FUNDAMENTALS TUTORIAL Presented By: JORDAN TOF PRODUCTS, INC. 990 Golden Gate Terrace Grass Valley, CA 95945 530-272-4580 / 530-272-2955 [fax] www.rmjordan.com [web] info@rmjordan.com [e-mail] This

### PHYS-2212 LAB Coulomb s Law and the Force between Charged Plates

PHYS-2212 LAB Coulomb s Law and the Force between Charged Plates Objectives To investigate the electrostatic force between charged metal plates and determine the electric permittivity of free space, ε

### Physics 2102 Gabriela González

Physics 2102 Gabriela González Electric charge Electric force on other electric charges Electric field, and electric potential Moing electric charges : current Electronic circuit components: batteries,

### AP Physics 1 and 2 Lab Investigations

AP Physics 1 and 2 Lab Investigations Student Guide to Data Analysis New York, NY. College Board, Advanced Placement, Advanced Placement Program, AP, AP Central, and the acorn logo are registered trademarks

### ELECTRON SPIN RESONANCE Last Revised: July 2007

QUESTION TO BE INVESTIGATED ELECTRON SPIN RESONANCE Last Revised: July 2007 How can we measure the Landé g factor for the free electron in DPPH as predicted by quantum mechanics? INTRODUCTION Electron

### Thermal Diffusivity, Specific Heat, and Thermal Conductivity of Aluminum Oxide and Pyroceram 9606

Report on the Thermal Diffusivity, Specific Heat, and Thermal Conductivity of Aluminum Oxide and Pyroceram 9606 This report presents the results of phenol diffusivity, specific heat and calculated thermal

### Chap. 6 Proportional Counters

Chap. 6 Proportional Counters Consider the drift motion of an ion in a simple ion chamber. The ions will have a thermal velocity plus a component along the field lines. Then after traveling for a mean-free-path

### Special Relativity and Electromagnetism Yannis PAPAPHILIPPOU CERN

Special Relativity and Electromagnetism Yannis PAPAPHILIPPOU CERN United States Particle Accelerator School, University of California - Santa Cruz, Santa Rosa, CA 14 th 18 th January 2008 1 Outline Notions

### 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

### Candidate Number. General Certificate of Education Advanced Level Examination June 2014

entre Number andidate Number Surname Other Names andidate Signature General ertificate of Education dvanced Level Examination June 214 Physics PHY4/1 Unit 4 Fields and Further Mechanics Section Wednesday

### Chapter 27 Magnetic Field and Magnetic Forces

Chapter 27 Magnetic Field and Magnetic Forces - Magnetism - Magnetic Field - Magnetic Field Lines and Magnetic Flux - Motion of Charged Particles in a Magnetic Field - Applications of Motion of Charged

### Physics Lab Report Guidelines

Physics Lab Report Guidelines Summary The following is an outline of the requirements for a physics lab report. A. Experimental Description 1. Provide a statement of the physical theory or principle observed

### Carbon Dioxide and an Argon + Nitrogen Mixture. Measurement of C p /C v for Argon, Nitrogen, Stephen Lucas 05/11/10

Carbon Dioxide and an Argon + Nitrogen Mixture Measurement of C p /C v for Argon, Nitrogen, Stephen Lucas 05/11/10 Measurement of C p /C v for Argon, Nitrogen, Carbon Dioxide and an Argon + Nitrogen Mixture

### Physics 112 Homework 5 (solutions) (2004 Fall) Solutions to Homework Questions 5

Solutions to Homework Questions 5 Chapt19, Problem-2: (a) Find the direction of the force on a proton (a positively charged particle) moving through the magnetic fields in Figure P19.2, as shown. (b) Repeat

### Experimental Question 1: Levitation of Conductors in an Oscillating Magnetic Field SOLUTION ( )

a. Using Faraday s law: Experimental Question 1: Levitation of Conductors in an Oscillating Magnetic Field SOLUTION The overall sign will not be graded. For the current, we use the extensive hints in the

### PHOTOELECTRIC EFFECT AND DUAL NATURE OF MATTER AND RADIATIONS

PHOTOELECTRIC EFFECT AND DUAL NATURE OF MATTER AND RADIATIONS 1. Photons 2. Photoelectric Effect 3. Experimental Set-up to study Photoelectric Effect 4. Effect of Intensity, Frequency, Potential on P.E.

### LABORATORY V MAGNETIC FIELDS AND FORCES

LABORATORY V MAGNETIC FIELDS AND FORCES Magnetism plays a large part in our modern world's technology. Magnets are used today to image parts of the body, to explore the mysteries of the human brain, and

### Magnetic Fields and Their Effects

Name Date Time to Complete h m Partner Course/ Section / Grade Magnetic Fields and Their Effects This experiment is intended to give you some hands-on experience with the effects of, and in some cases

### PPT No. 26. Uniformly Magnetized Sphere in the External Magnetic Field. Electromagnets

PPT No. 26 Uniformly Magnetized Sphere in the External Magnetic Field Electromagnets Uniformly magnetized sphere in external magnetic field The Topic Uniformly magnetized sphere in external magnetic field,

### Physics 126 Practice Exam #3 Professor Siegel

Physics 126 Practice Exam #3 Professor Siegel Name: Lab Day: 1. Which one of the following statements concerning the magnetic force on a charged particle in a magnetic field is true? A) The magnetic force

### The Structure of the Atom

Before You Read Review scientific law Define the following terms describes a relationship in nature that is supported by many experiments theory an explanation supported by many experiments; is still subject

### 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

### Experiment 7: Forces and Torques on Magnetic Dipoles

MASSACHUSETTS INSTITUTE OF TECHNOLOY Department of Physics 8. Spring 5 OBJECTIVES Experiment 7: Forces and Torques on Magnetic Dipoles 1. To measure the magnetic fields due to a pair of current-carrying

### Phys222 Winter 2012 Quiz 4 Chapters 29-31. Name

Name If you think that no correct answer is provided, give your answer, state your reasoning briefly; append additional sheet of paper if necessary. 1. A particle (q = 5.0 nc, m = 3.0 µg) moves in a region

### MAGNETISM MAGNETISM. Principles of Imaging Science II (120)

Principles of Imaging Science II (120) Magnetism & Electromagnetism MAGNETISM Magnetism is a property in nature that is present when charged particles are in motion. Any charged particle in motion creates

### Candidate Number. General Certificate of Education Advanced Level Examination June 2012

entre Number andidate Number Surname Other Names andidate Signature General ertificate of Education dvanced Level Examination June 212 Physics PHY4/1 Unit 4 Fields and Further Mechanics Section Monday

### How did scientists determine the structures that are inside an atom?

Chapter 4 Atomic Structure 4.1 Defining the Atom 4.2 Structure of the Nuclear Atom 4.3 Distinguishing Among Atoms 1 Copyright Pearson Education, Inc., or its affiliates. All Rights Reserved. CHEMISTRY

### Exam 2 Practice Problems Part 2 Solutions

Problem 1: Short Questions MASSACHUSETTS INSTITUTE OF TECHNOLOGY Department of Physics 8. Exam Practice Problems Part Solutions (a) Can a constant magnetic field set into motion an electron, which is initially

### Laboratory Exercise 10 FUNDAMENTAL and SUBATOMIC PHYSICS

Laboratory Exercise 10 FUNDAMENTAL and SUBATOMIC PHYSICS The first and last parts of this exercise are concerned with two subatomic elementary particles the electron, which is stable, and the pion, an

### Cambridge International Examinations Cambridge International General Certificate of Secondary Education

ambridge International Examinations ambridge International General ertificate of Secondary Education *0123456789* PHYSIS 0625/02 Paper 2 Multiple hoice (Extended) For Examination from 2016 SPEIMEN PPER

### AP2 Magnetism. (c) Explain why the magnetic field does no work on the particle as it moves in its circular path.

A charged particle is projected from point P with velocity v at a right angle to a uniform magnetic field directed out of the plane of the page as shown. The particle moves along a circle of radius R.

### Electrostatics Problems

Name AP Physics B Electrostatics Problems Date Mrs. Kelly 1. How many excess electrons are contained in a charge of 30 C? 2. Calculate and compare the gravitational and electrostatic force between an electron

### A2 Physics Unit 7 Magnetic Fields. Mr D Powell

A Physics Unit 7 Magnetic Fields Mr D Powell Chapter Map Circumference circle = r Distance trav = ¼ * r WD = Fd = d*mv /r Sub in eq to give B B 7.1 Current-carrying conductors in a magnetic field Specification

### FORCE ON A CURRENT IN A MAGNETIC FIELD

7/16 Force current 1/8 FORCE ON A CURRENT IN A MAGNETIC FIELD PURPOSE: To study the force exerted on an electric current by a magnetic field. BACKGROUND: When an electric charge moves with a velocity v

### Reflection and Refraction

Equipment Reflection and Refraction Acrylic block set, plane-concave-convex universal mirror, cork board, cork board stand, pins, flashlight, protractor, ruler, mirror worksheet, rectangular block worksheet,

### PENDULUM PERIODS. First Last. Partners: student1, student2, and student3

PENDULUM PERIODS First Last Partners: student1, student2, and student3 Governor s School for Science and Technology 520 Butler Farm Road, Hampton, VA 23666 April 13, 2011 ABSTRACT The effect of amplitude,

### Physics 2B. Lecture 29B

Physics 2B Lecture 29B "There is a magnet in your heart that will attract true friends. That magnet is unselfishness, thinking of others first. When you learn to live for others, they will live for you."

### Experiment 9: Biot -Savart Law with Helmholtz Coil

Experiment 9: Biot -Savart Law with Helmholtz Coil ntroduction n this lab we will study the magnetic fields of circular current loops using the Biot-Savart law. The Biot-Savart Law states the magnetic

### 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

### 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,

### CHAPTER D1 ION OPTICS OF MAGNETIC/ELECTRIC SECTOR MS

Back to Basics Section D: Ion Optics CHAPTER D1 ION OPTICS OF MAGNETIC/ELECTRIC SECTOR MS TABLE OF CONTENTS QuickGuide...369 Summary...369 Preamble...371 MassAnalysisofIons...371 MagneticSector...371 ElectrostaticAnalyser(ElectricSector)...375

### Graphical Presentation of Data

Graphical Presentation of Data Guidelines for Making Graphs Titles should tell the reader exactly what is graphed Remove stray lines, legends, points, and any other unintended additions by the computer

### Lecture 13. Magnetic Field, Magnetic Forces on Moving Charges. Outline:

Lecture 13. Magnetic Field, Magnetic Forces on Moving Charges. Outline: Intro to Magnetostatics. Magnetic Field Flux, Absence of Magnetic Monopoles. Force on charges moving in magnetic field. 1 Intro to

### Charges, voltage and current

Charges, voltage and current Lecture 2 1 Atoms and electrons Atoms are built up from Positively charged nucleus Negatively charged electrons orbiting in shells (or more accurately clouds or orbitals) -

### physics 112N magnetic fields and forces

physics 112N magnetic fields and forces bar magnet & iron filings physics 112N 2 bar magnets physics 112N 3 the Earth s magnetic field physics 112N 4 electro -magnetism! is there a connection between electricity

### MEASUREMENT OF VISCOSITY OF LIQUIDS BY THE STOKE S METHOD

130 Experiment-366 F MEASUREMENT OF VISCOSITY OF LIQUIDS BY THE STOKE S METHOD Jeethendra Kumar P K, Ajeya PadmaJeeth and Santhosh K KamalJeeth Instrumentation & Service Unit, No-610, Tata Nagar, Bengaluru-560092.

### Ampere's Law. Introduction. times the current enclosed in that loop: Ampere's Law states that the line integral of B and dl over a closed path is 0

1 Ampere's Law Purpose: To investigate Ampere's Law by measuring how magnetic field varies over a closed path; to examine how magnetic field depends upon current. Apparatus: Solenoid and path integral