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ISNS 4371 - Phenomena of Nature ISNS 3371 - Phenomena of Nature Dr. Phillip Anderson
ISNS 4371 - Phenomena of Nature Spring 2007 – INSTRUCTOR: – Dr. Phillip C. Anderson 972 -883 -2875 — Room FO 2. 708 D cell: 469 -371 -3744 email: phillip. anderson [email protected] edu – TEACHING ASSISTANTS: – Jeff Peden 972 -883 -2867 — Room FO 1. 426 email: [email protected] net – OFFICE HOURS: – Dr. Anderson: Tuesday/Thursday 10: 00 AM– 11: 00 PM and by appointment – Mr. Peden: Tuesday 2: 00 PM - 3: 00 PM and by appointment.
ISNS 4371 - Phenomena of Nature Spring 2007 TEXT: – Conceptual Physical Science Explorations by: Hewitt, Suchocki, Hewitt – Slides will be available on web at www. utdallas. edu/~pca 015000 GRADING: – Exams (3)2 Exams @ 25% each February 8 th and March 15 th = 50% – Final Exam (April 24 @ 8 am) = 30% – Quizzes = 10% Short quizzes may be given during any class period – Homework – See attached sheet - = 10%
ISNS 4371 - Phenomena of Nature Spring 2007 ATTENDANCE is important since exams and quizzes are based on material covered in class. – A seating chart will be made on the second day of class. – If your grade is on the borderline between two letters, your attendance will be used to determine whether to raise or lower your grade
ISNS 4371 - Phenomena of Nature For the benefit of your fellow students and your instructors, please practice common courtesy with regard to all class interactions. – Please be sure your cell phone and beeper are OFF. – Be on time for class. – Do not leave class early. You will be disturbing other students. Quizzes may be given and attendance may be taken at any time – If you must miss a class inform Dr. Anderson in advance by phone or e-mail. – Please do not use your laptops and the wireless network to play games, attend chat rooms, etc… It is important to pay attention in class. We will move quickly and each new topic will build on concepts previously covered. If you fall behind at any time, you will find it difficult to catch up. Quizzes may by given at any time and may cover topics from the current or a previous class.
ISNS 4371 - Phenomena of Nature We hope this class will be a rewarding experience for you. We will be performing laboratory experiments in almost every class demonstrating relevant principles of physics. We will cover many concepts that will explain how the world works and hope you will gain some appreciation for the intricacies of the natural world. This is a demanding course. We will cover many important concepts from physics and chemistry and will use some simple mathematics throughout the course. We will move quickly and each new topic will build on concepts previously covered. If you fall behind at any time, you will find it difficult to catch up. You are expected to study for every class. We may have quizzes at any time.
ISNS 4371 - Phenomena of Nature Spring 2007 - HOMEWORK PROJECT Select an atticle from a newspaper or a news magazine dealing with science and its relationship with society, that is, with the environment, weather, global warming, space exploration, health, dna, genetic engineering, etc. Articles dealing with purely social issues will not be accepted. Write a report on the article. The report must contain: 1. Title of the article. 2. Name of publication (Dallas Morning News, New York Times, Time, Newsweek. Reports from the internet are acceptable. ) Note that the Dallas Morning news has a science section every Monday. 3. Date of publication. 4. A paragraph of two or three sentences on the main theme of the article and how it relates to a current science issue. 5. Your name and assigned seat number in the upper right hand corner.
ISNS 4371 - Phenomena of Nature Spring 2007 — HOMEWORK PROJECT Attach a copy of the article to the report. Please staple the article to the report before coming to class. We do not have a stapler in class. Reports are due every Tuesday starting on January 16 with the last one due on April 17. Late reports will not be accepted. A report is considered late if not handed in by the end of class (10: 45 am) on the date due.
ISNS 4371 - Phenomena of Nature Exams and Quizzes The exams will be held on February 8 th and March 15 th. The final will be on April 24 th @ 8: 00 AM. I will provide you with a review handout a week prior to the exams. We will have two review sessions the week of the exam at a special times to be determined. There will be about 10 - 13 quizzes. I will drop the worst three. The exams and quizzes will deal only with subjects covered in class. However, you should read the relevant portions of the text before and/or after class as they will provide you with more detailed descriptions of the covered subjects. A slightly different description may also give you a better understanding of the subject matter.
ISNS 4371 - Phenomena of Nature SYLLABUS - Spring 2007 1. Introduction Exploration of Nature, Science – A Way of Knowing Fundamental quantities Measurement units Scales of distances 2. The Newtonian Universe Vectors, Scalars Motion - distance, velocity, acceleration Force - static, net Mass, momentum, impulse Newton’s Laws of Motion Gravity -force, acceleration, weightlessness
ISNS 4371 - Phenomena of Nature 3. Energy and Matter - States of Matter Energy, Work Law of Conservation of Energy Forms of Energy Transformation of energy Power Heat, Temperature Transfer of heat - Conduction, Convection, Radiation, Change of state of matter Gases - gas laws, Boyle, Charles, General First Law of Thermodynamics Diffusion of gases Archimedes’ Principle Bernoulli Effect
ISNS 4371 - Phenomena of Nature 4. Exploring the Universe Wave Motion Waves, Properties of Waves Standing Waves, Resonance, Interference, Beats Sound Pitch vs. Frequency, Loudness vs. Intensity Timbre vs. Harmonics Light Electromagnetic Spectrum - Color Refraction, Reflection Polarization Doppler Effect Lenses and Mirrors, Optical Instruments Scattering - Blue Sky - Red Sunsets Rainbows Atmospheric Pollution
ISNS 4371 - Phenomena of Nature Radiation Black Body, Planck’s Law Wien’s and Stefan’s Laws 5. Electricity and Magnetism Electrostatics Fields and Potential, Energy and Power Electrical units: Volt, Ampere, Ohm Circuits - Series and Parallel Magnetism Electric Currents and Magnetic Fields Motors, Generators, Transformers Power Distribution
ISNS 4371 - Phenomena of Nature 6. The Material World Particles of Matter – Atoms, Atomic Structure Atomic Spectra – Hydrogen Atom What is Inside the Atom? The Nucleus – Geochronology, Stability, Radioactivity, Fission, Fusion Energy of the Future
ISNS 4371 - Phenomena of Nature Science What is Science? – Observation and experimentation directed toward understanding of the natural world. [Science is] an imaginative adventure of the mind seeking truth in a world of mystery. Sir Cyril Herman Hinshelwood (1897 -1967) English chemist. Nobel prize 1956. Science is facts; just as houses are made of stone, so is science made of facts; but a pile of stones is not a house, and a collection of facts is not necessarily science. Jules Henri Poincaré (18541912) French mathematician.
ISNS 4371 - Phenomena of Nature Why study science? – We live in a world surrounded by science and technology. – Our problems and their solutions are bound up with science. – We are called upon to make decisions, to vote, hopefully informed, on issues affecting our lives. – Many of these issues have a significant scientific component.
ISNS 4371 - Phenomena of Nature Why study science? (Continued) – For the convenience of the study of science, the subject is frequently divided into neat packages called biology, chemistry, geology, physics, astronomy --– Nature is not so divided - Each scientific discipline views nature from a different perspective, but all are studying the same world. – This course will focus on a fundamental or general look at nature. It will be based on physics, the study of the principles that govern the natural world.
ISNS 4371 - Phenomena of Nature Why are we able to study nature? • Fundamental assumptions about nature: – Order exists in nature – in the universe. – Order can be discovered by observation and experimentation. – Laws of nature are constant in time and place. Philosophical approach to the study of nature. • Aristotle, Plato – Senses cannot be relied on – Must use reason and insights of human mind.
ISNS 4371 - Phenomena of Nature Scientific approach to the study of nature • Copernicus and Galileo introduced observation and experimentation in the 16 th century. • Science is not a set of facts. • It is a way of conducting a dialogue about our physical surroundings. • The scientific method consists of careful observation of nature and an open-minded creative search for general ideas that agree with and predict those observations. • To be scientific, a statement must be capable of being proven wrong.
ISNS 4371 - Phenomena of Nature Scientific approach to the study of nature. • Observation and experimentation set science apart from other ways of knowing - ways that are not less important - just different – Philosophy – Reason – Logic – Art – Appreciation of form – Beauty • Pseudoscience statements: – Hypothesis that cannot be tested with reproducible results; Cold fusion, ufo's, astrology. . .
ISNS 4371 - Phenomena of Nature The Zodiac Why the Sun appears to move steadily eastward along the ecliptic, through the constellations of the zodiac. As Earth orbits the Sun, we see the Sun against the background of different zodiac constellations at different times of year. For example, on August 21 the Sun appears to be in the constellation Leo. Defines astral calendar.
ISNS 4371 - Phenomena of Nature Zodiac Animation When astrology began - few thousand years ago - astrological sign supposed to represent the constellation Sun appeared in on your birth date. However, because of precession - no longer case for most people signs are about a month off. Sign actually corresponds to constellation the Sun would have appeared in on your birthday 2000 years ago
ISNS 4371 - Phenomena of Nature
ISNS 4371 - Phenomena of Nature The Scientific Method
ISNS 4371 - Phenomena of Nature Scientific approach to the study of nature. • Hypothesis – An educated guess to answer a question about nature • Scientific Law: – A hypothesis that has been tested over and over again and has not been contradicted • Scientific fact: – Something that competent observers can observe and agree to be true • Scientific Theory: – Synthesis of facts and well-tested hypothesis. – General principle offered to explain a set of phenomena or observed facts. – Not all scientific predictions can be tested directly • Core of earth • Sun—energy • Expansion of the universe • Require models—creative thought – No ultimate truths—all Provisional • Ok as long as they are not contradicted
ISNS 4371 - Phenomena of Nature Scientific approach to the study of nature. Model: – Simplified version of reality used to describe aspects of nature. – Not synonymous with reality. – Based on assumptions that may simplify some aspects of nature, or may be incomplete statements about nature – Useful to make predictions that can be verified by experimentation or observation.
ISNS 4371 - Phenomena of Nature Hallmarks of Science • Modern science seeks explanations for observed phenomena that rely solely on natural causes. • Science progresses through the creation and testing of models of nature that explain the observations as simply as possible. • A scientific model must make testable predictions about natural phenomena that would force us to revise or abandon the model if the predictions do not agree with observations. The hypotheses we accept ought to explain phenomena which we have observed. But they ought to do more than this: our hypotheses ought to foretell phenomena which have not yet been observed. William Whewell (1794 -1866) English mathematician, philosopher.
ISNS 4371 - Phenomena of Nature Occam’s Razor The idea that scientists should prefer the simpler of two models that agree equally well with observations - the second hallmark - after medieval scholar William of Occam (1285 - 1349). For instance, original model of Copernicus (Sun-centered) did not match the data noticeably better than Ptolemy's model (Earth-centered). Thus, a purely data-driven judgment based on the third hallmark might have led scientists to immediately reject the Sun-centered idea. Instead, many scientists found elements of the Copernican model appealing, such as the simplicity of its explanation for apparent retrograde motion. Was kept alive until Kepler found a way to make it work.
ISNS 4371 - Phenomena of Nature Galileo Galilei (1564 – 1642) I do not feel obliged to believe that the same God who endowed us with sense, reason, and intellect intended us to forgo their use. I have never met a man so ignorant that I couldn’t learn something from him. All truths are easy to understand once they are discovered, the point is to discover them.
ISNS 4371 - Phenomena of Nature Albert Einstein (1879 -1955) When you are courting a nice girl an hour seems like a second. When you sit on a red-hot cinder a second seems like an hour. That's relativity. If my theory of relativity is proven correct, Germany will claim me as a German and France will declare that I am a citizen of the world. Should my theory prove untrue, France will say that I am a German and Germany will declare that I am a Jew. If we knew what it was we were doing, it would not be called research, would it? The most incomprehensible thing about our universe is that it can be comprehended. I shall never believe that God plays dice with the world (speaking about quantum mechanics). A little knowledge is a dangerous thing. So is a lot.
ISNS 4371 - Phenomena of Nature "The airplane stays up because it doesn't have the time to fall. " Orville Wright. "Physics is like sex: sure, it may give some practical results, but that's not why we do it. ” Richard Feynman. The most exciting phrase to hear in science, the one that heralds new discoveries, is not 'Eureka!' ('I found it!') but rather 'hmm. . that's funny. . . '" Isaac Asimov. Examples of “hmmm… that’s funny”: Discovery of penicillin by Alexander Fleming in 1929. Discovery of X-rays by Wilhelm Röntgen in 1895.
ISNS 4371 - Phenomena of Nature FUNDAMENTAL QUANTITIES QUANTITY UNIT DEFINITION Length Meter Mass Kilogram =1000 grams 1 gram = mass of 1 cubic centimeter of water at 4 C. Time Second Time for a cesium atom to make 9, 192, 631, 770 vibrations Force Newton Force to accelerate 1 kilogram by 1 meter per second Energy Joule Amount of work done by a force of 1 Newton acting over a distance of 1 meter Temperature Kelvin 1/273 of temperature of freezing point of water Length of the path traveled by light in a vacuum during 1/299, 792, 458 second
ISNS 4371 - Phenomena of Nature MEASUREMENT SYSTEMS ENGLISH Developed in England – Used in the United States METRIC Developed after the French Revolution (1791) INTERNATIONAL (SI) The modern version of the metric system - formally established in 1960 by the International Conference on Weights and Measures
ISNS 4371 - Phenomena of Nature EXPONENTIAL NOTATION 1, 000, 000 109 giga G 1, 000 106 mega M 1, 000 103 kilo k 100 102 hecto h 10 101 deka da 1 100 - - 0. 1 10 -1 deci d 0. 01 10 -2 centi c 0. 001 10 -3 milli m 0. 000001 10 -6 micro 0. 00001 10 -9 nano n
ISNS 4371 - Phenomena of Nature SCALES OF DISTANCE Astronomical AU Average distance between the Earth and the Sun Unit Light Year LY Distance light travels in one Year 1 LY = 186, 000 Miles/Second x 31, 500, 000 Seconds = 5. 8 x 1012 Miles Parsec PC Distance of an object that would have a stellar parallax of 1 Second of Arc 1 PC = 3. 26 LY = 206, 000 AU Angstrom A Nanometer nm A distance of 10 -9 meter or 10 -7 cm Visible light has wavelengths from 400 to 700 nm A distance of 1 x 10 -8 cm Visible Light has wavelengths from 4000 to 7000 A
ISNS 4371 - Phenomena of Nature DEFINITIONS Scalar A quantity that has only size or magnitude. Examples: mass, inertia, weight, temperature Vector A quantity that has both size and direction. Examples: velocity, acceleration, force