Highland Park Physics I Curriculum Semester II weeks 12-18

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1 NAME OF UNIT: Magnetism NAME OF UNIT: Modern Physics Components Weeks Weeks Unit Name Magnetism and Electromagnetic Induction Quantum Theory Introduction Electricity can be generated through the understanding of magnetism and electromagnetic induction. Microwave ovens, lasers televisions, computer monitors and home security systems are a few of the many devices that depend upon the quantum nature of light and matter. These are modern devices that have entered the culture and have become a defining component of today s world. An understanding of their purpose and operation will lead to Short Descriptive Overview Generalizations/Enduring Understandings Concepts Electromagnetic induction can be used to generate electricity. An understanding of generating electricity allows for a deeper understanding of everyday uses such as electric motor, microphones and speakers. 1. Magnets have two poles, north and south. 2. Like poles repel, unlike poles attract. 3. Current carrying wires generate a magnetic field. 4. The magnetic force, velocity of electric charges and the magnetic field are all at right angles to each other. 5. Electric generators and electric motors are dependent upon electromagnetism 6. Mass spectrometers are used to separate ions based on different masses General properties of magnets Magnetic fields around permanent magnets Electromagnetism A microscopic picture of magnetic materials Forces on currents in magnetic fields Loudspeakers informed decisions regarding operation and value. Two phenomena that cannot be explained by Maxwell s theory open the study and conclude that waves behave as particles. Hot body radiation and the photoelectric effect are the contributions of Planck and Einstein in explaining the two phenomena. Compton s experiments, which tested Einstein s theory and verified the particulate nature of light and other forms of electromagnetic radiation, are explored. The symmetry evident in the dual nature of matter is examined using de Broglie s matter waves and implications of the Heisenberg uncertainty principle. 1. Light is a discrete, or quantized, bundle of momentum and energy. 2. Atom sized particles behave as waves that show diffraction and interference effects. Hot body spectrum Emission of hot body radiation Photoelectric effect Quantum theory Wave theory Compton Effect 08/08/2011 1

2 Guiding/Essential Questions Galvanometers The force on a single charged particle Faraday s discovery Electromotive force Electric generators Alternating-current generator Lenz s law Self-Inductance Transformers Mass of an electron The mass spectrometer Electromagnetic waves Production of electromagnetic waves Reception of electromagnetic waves X-Rays 1. What is magnetism? 2. Describe the right hand rule. 3. How do you demonstrate the effects of magnetic forces? 4. What are the three most common magnetic elements? 5. If a current-carrying wire is bent in a loop, why is the magnetic field inside the loop stronger than the magnetic field outside? 6. How are Oersted s and Faraday s results similar? How are they different? 7. What does EMF stand for? 8. Why is the name EMF inaccurate? 9. What is the armature of an electric generator? 10. What is the difference between a generator and a motor? 11. State Lenz s law. 12. What is the mass of an electron? 13. What is an electrons charge? 14. What are isotopes? Particle-like properties of the electromagnetic spectrum Wave nature of matter Dual Nature of particles and waves Heisenberg Uncertainty principle 1. What is distinctive about the spectrum emitted by a hot body? 2. What is the basic theory that underlies the emission of hotbody radiation? 3. What is the photoelectric effect? 4. How does the quantum theory explain the photoelectric effect? 5. Why doesn t the wave theory explain the photoelectric effect? 6. What is the Compton Effect? 7. What is a photon? 8. How can we explain the Compton effect in terms of momentum and energy of the photon? 9. What experiments demonstrate the particle-like properties of electromagnetic radiation? 10. What is the evidence for the wave nature of matter? 11. How can the wavelength be related to particle momentum? 12. What is the dual nature of waves and particles 08/08/2011 2

3 Learning Targets Characteristics and behavior of magnets Application of magnets (motors, generators and transformers) The photoelectric effect The wave-particle duality Nuclear physics (fission, fusion, disintegration and the mass equivalent of energy) Formative Assessment Summative Assessment Teacher-made test on Chapter Teacher-made test on Chapter 27 TEKS Processes Scientific Process Skills: (1) Scientific processes. The student, for at least 40% of instructional time, conducts field and laboratory investigations using safe, environmentally appropriate, and ethical practices. The student is expected to: (A) demonstrate safe practices during field and laboratory investigations; and (B) Make wise choices in the use and conservation of resources and the disposal or recycling of materials. (2) Scientific processes. The student uses scientific methods during field and laboratory investigations. The student is expected to: (A) plan and implement experimental procedures including asking questions, formulating testable hypotheses, and selecting equipment and technology; (B) make quantitative observations and measurements with precision; (C) organize, analyze, evaluate, make inferences, and predict trends from data; (D) communicate valid conclusions; (F) Read the scale on scientific instruments with precision. (3) Scientific processes. The student uses critical thinking and scientific problem solving to make informed decisions. The student is expected to: (B) express laws symbolically and employ mathematical procedures including vector addition and right-triangle geometry to solve physical problems; (C) evaluate the impact of research on scientific thought, society, and the environment; (D) describe the connection between physics and future careers; and (E) Research and describe the history of physics and contributions of scientists. TEKS Concepts (5) Science concepts. The student knows the nature of forces in the physical world. The student is expected to: (A) research and describe the historical development of the concepts of gravitational, electromagnetic, weak nuclear, and strong nuclear forces; Supporting (D) identify examples of electric and magnetic forces in everyday life; Supporting (G) investigate and describe the relationship between electric and magnetic fields in applications such as generators, (8) Science concepts. The student knows simple examples of atomic, nuclear, and quantum phenomena. The student is expected to: (A) describe the photoelectric effect and the dual nature of light; Readiness (B) compare and explain the emission spectra produced by various atoms; Supporting (C) describe the significance of mass-energy equivalence and apply it in explanations of phenomena such as nuclear 08/08/2011 3

4 Processes and Skills Topics Essential Facts motors, and transformers; Supporting (6) Science concepts. The student knows forces in nature. The student is expected to: (B) research and describe the historical development of the concepts of gravitational, electrical, and magnetic force; Readiness (C) identify and analyze the influences of charge and distance on electric forces; Readiness (F) Identify examples of electrical and magnetic forces in everyday life. Supporting Observing, formulating models, measuring, predicting, inferring, communicating, using numbers, interpreting data, defining frames of reference, using space/time relationships, comparing and contrasting, manipulation of vectors, making and interpreting graphs, controlling variables Magnetism Electromagnetic Induction 1. Magnets have two poles, north and south. 2. Like poles repel, opposite poles attract. 3. Magnetic field lines leave a north pole and end on a south pole. 4. A current carrying wire will generate a magnetic field. 5. Magnetic domains that are aligned make a magnetic substance. 6. Current can be generated using a magnet and a coiled wire. stability, fission, and fusion; Supporting (D) give examples of applications of atomic and nuclear phenomena such as radiation therapy, diagnostic imaging, and nuclear power and examples of applications of quantum phenomena such as digital cameras. Supporting (H) describe evidence for and effects of the strong and weak nuclear forces in nature. Observing, formulating models, measuring, predicting, inferring, communicating, using numbers, interpreting data, defining frames of reference, using space/time relationships, comparing and contrasting, manipulation of vectors, making and interpreting graphs, controlling variables Waves Behave Like Particles Particles Behave Like Waves 1. A hot body emits visible light as well as infrared and ultraviolet rays. 2. As the temperature of a hot body increases, the frequency for maximum intensity increases. 3. As the temperature of a hot body increase, the intensity of the ultraviolet emission increases. 4. The emission of electrons when electromagnetic radiation falls on an object is called the photoelectric effect. 5. The threshold frequency is the minimum value of the radiation frequency needed to eject electrons from a metal. 6. The threshold frequency varies with the metal. 7. Einstein proposed that light was composed of discrete bundles of energy called photons. 8. The energy of a photon depends on the frequency of light. 9. Excess energy of the photon above the threshold frequency becomes the kinetic energy of the electron. 10. The photoelectric effect demonstrates that a photon has kinetic energy. 11. Einstein predicted that the photon should have 08/08/2011 4

5 Journal Writing Language of Instruction Highland Park Physics I Curriculum Polarized, magnetic fields, magnetic flux, right hand rule, solenoid, electromagnet, domain, galvanometer, electric motor, armature, electromagnetic induction, electromotive force, electric generator, Lenz s law, eddy currents, selfinductance, transformer, primary coil, secondary coil, mutual inductance, step-up transformer, step-down transformer, isotopes, mass spectrometer, electromagnetic wave, antenna, electromagnetic radiation momentum. 12. The Compton effect demonstrates that the photon has momentum. 13. The shift in the energy of scattered photons is called the Compton effect. 14. A photon is a particle that has energy and momentum but it has no mass and travels at the peed of light. 15. The de Broglie experiment demonstrated that particles have wave-like behavior. 16. Comparing the diffraction pattern of a beam of electrons with the diffraction pattern of x-rays, G. P. Thomson demonstrated that particles have wave-like behavior. 17. The dual wave and particle description of light and matter resulted in the Heisenberg uncertainty principle. 18. The Heisenberg Uncertainty Principle states that it is impossible to measure both the position and the momentum of a particle at the same time. Compton effect, de Broglie wavelength, Heisenberg uncertainty principle, photoelectric effect, photon, quantized, threshold frequency, work function State Assessment Connections National Assessment Connections Misconceptions 1. Einstein received the Nobel price for the photoelectric effect because it was confirmed by Millikan s experiment. 2. Increasing the intensity of the light source does not raise the energy of the ejected electrons but it does increase the number of electrons that are ejected. 3. Dim blue light will release electrons with more energy while the red light will cause more electrons to be emitted. 4. Quantum phenomena do not always adhere to Newton s 08/08/2011 5

6 laws. 5. The particle and wave aspects must be taken together as light does not simply change its nature to suit the situation. Resources Student Investigations/Student Products Core Labs Resources Pocket Lab Monopoles? on pg 557 of the text Pocket Lab Funny balls on pg 559 of the text Pocket Lab 3-D magnetic fields on pg 564 on the text Pocket Lab Making currents on pg 585 of the text Pocket Lab Motor and generator on pg 588 of the text Pocket Lab Slow motor on pg 591 of the text Pocket Lab Slow magnet on pg 593 of the text Pocket Lab Rolling Along on pg 607 of the text Pocket Lab Catching the wave on pg 614 on the text Pocket Lab More radio stuff on pg 617 on the text Magnetic Pole Lab Magnetism in a current carrying wire Dallas County Video Streaming- Power Videos:Search by TEKS Pocket Lab Glows in the Dark on pg 627 in the text Pocket Lab See the Light on pg 630 in the text Emission Spectrum Lab Lab Simulations Dallas County Video Streaming- Power Videos:Search by TEKS Textbook Correlation Other Curricular Connection (ELA, Math, S.S., Technology) Physics: Principles and Problems Chapter Released TIMMS Questions Regents Exam Resources AAPT Physical Science Resource Center Virtual Physics Simulations Magnetics; Faraday Lab Physics: Principles and Problems Chapters Released TIMMS Questions Regents Exam Resources AAPT Physical Science Resource Center Virtual Physics Simulations Photoelectric; Blackbody; Alpha & Beta Decay 08/08/2011 6

7 Science TEKS Toolkit Proquest (Physics & Society) pg Science TEKS Toolkit Proquest (Physics & Society) pg 08/08/2011 7