Physics 207, Sections: 302/602 313/616 General Physics Faculty Instructors: Michael Winokur Deniz Yavuz Agenda for Today l Course Introduction v Course structure v Course scope v Begin chapter 1 Course Homepage: http://www.physics.wisc.edu/undergrads/courses/fall2011/207/ Physics 207: Text, Homework, Lecture, Discussion, Lab, Exams Physics 207: Lecture 1, Pg 1 General Announcements l Text: Randall Knight, Physics for Scientists and Engineers with Modern Physics v Reading Assignments (due BEFORE class) For Wed. Sep. 7 th : Chapters 1 & 2 (2.1-2.4) Position, Time, Change (i.e. motion), Vectors, Units, Assessment New: Reading Quizzes v HW0: Due Thurs. 9/8 at 11:59 PM (Mastering Physics Practice Set ) Mastering Physics registration: see http://www.physics.wisc.edu/undergrads/courses/fall11/207/hw.htm Homework will usually be due by 11:59 PM on Tuesdays with a 1% per hour penalty (up to 50% maximum) Physics 207: Lecture 1, Pg 2 Page 1
l Labs Announcements, cont d v http://www.physics.wisc.edu/undergrads/courses/fall2011/207/labs.htm v Rm. 4310 Chamberlin Hall, begin on Monday Sept. 12 v At most, one formal write-ups, mostly worksheets l Lectures: Mondays & Wednesdays, 8:50-9:40am (Revised notes will be posted at the course website) l Scope: Chapters 1 through 21 (except 14) in Knight Class moves very quickly! Physics 207: Lecture 1, Pg 3 Announcements, cont d l Honors students: One Friday seminar per week (including exams weeks, may miss up to two) + fun group project l Drop in tutoring: In room 2131 Chamberlain (shared with Physics 201, starting on 9/12) http://www.physics.wisc.edu/undergrads/courses/current/207/consult.htm l Discussion Sections: Start Wednesday v Thursday: centers on cooperative learning exercises v Tuesday: homework & class business v Remember that your TAs have other obligations (they are not 27/7 tech support services) Physics 207: Lecture 1, Pg 4 Page 2
Grading l Several components: v Lecture: Occasional reading quizzes (2%) v Homework Sets (14%) v Exams: Three evening midterms (16%) and a final (22%) v Discussion section: (5%) Participation/attendance v Labs: (9%) Mostly worksheets (up to one formal write up) May miss up to one lab (with a valid excuse) (final grade will be lowered if more) Physics 207: Lecture 1, Pg 5 Lecture l Three main components: v Discussion class material» Selected topics from text v Demonstrations of physical phenomenon» Physics is an experimental science Example: Ping-pong ball bazooka Similar principle is used in needleless air gun injectors Act Physics 207: Lecture 1, Pg 6 Page 3
Lecture v Interactive exercise with conceptual Active Learning problems» Critical thinking and problem solving (Almost no memorization required) Physics 207: Lecture 1, Pg 7 A quick quiz on what not to do l Please read and study the following paragraph for a minute or so. l Last Fernday, George and Tony were in Donlon peppering gloopy saples and cleaming, burly greps. Suddenly, a ditty strezzle boofed into George s grep. Tony blaired, Oh George, that ditty strezzle is boofing your grep! l After reading and studying the paragraph, and without referring to the paragraph, please answer the following questions: Physics 207: Lecture 1, Pg 8 Page 4
A quick quiz on what not to do l 1. When were George and Tony in Donlon? l 2. What did the ditty strezzle do to George s grep? l 3. What kind of saples did George and Tony pepper? l 4. What was Tony s reaction? l 5. What do you imagine happened next? l 6. Based on the incidents in this story, do you think George and Tony will want to return to Donlon? Why or why not? Physics 207: Lecture 1, Pg 9 A quick quiz on what not to do l 1. When were George and Tony in Donlon? Fernday l 2. What did the ditty strezzle do to George s grep? Boofed l 3. What kind of saples did George and Tony pepper? Gloopy l 4. What was Tony s reaction? Blaired l 5. What do you imagine happened next? l 6. Based on the incidents in this story, do you think George and Tony will want to return to Donlon? Why or why not? So, do you think you did well on the quiz? What do you think you actually learned? Physics 207: Lecture 1, Pg 10 Page 5
Course Objectives l To begin to understand basic principles (e.g. Newton's Laws) and their consequences (e.g. conservation of momentum, etc.) l To solve problems using both quantitative and qualitative applications of these physical principles l To develop an intuition of the physical world l Rote use of formulas is not what physics is about Physics 207: Lecture 1, Pg 11 Scope of Physics 207 l Classical Mechanics: v Mechanics: How and why things work. Motion (dynamics), balance (statics), energy, vibrations Classical:» Not too fast (v << c), c speed of light» Not too small (d >> atom), atoms 10-9 m l Most everyday situations can be described in these terms. Most everyday situations can be described in these terms. v Path of baseball (or a ping pong ball) v Path of rubber ball bouncing against a wall v Vibrations in elastic materials (Vibration Demo) (These reflect Newton s Laws and forces) v Properties of matter; a roll of the dice (Thermodynamics) Physics 207: Lecture 1, Pg 12 Page 6
Chladni patterns See http://www.phys.unsw.edu.au/jw/chladni.html for more info Physics 207: Lecture 1, Pg 13 Chapter 1: l Position (where) and Time (when) v Time v Displacement versus time (velocity) v Systems of units v Dimensional Analysis v Significant digits l At right is the world s smallest biped: A single molecule of kinesin, walks along a cellular microtubule fiber, pulling along behind it a vesicle of nutrients http://www.ted.com/index.php/talks/sheila_patek_clocks_the_fastest_animals.html Physics 207: Lecture 1, Pg 14 Page 7
Chapter 1 & 2 Objectives l Understand particle one-dimensional motion l Use motion diagrams l Distinguish position, velocity & acceleration l Gain experience with vector algebra l Understand proper use of significant figures l Understand position vs. time graphs Physics 207: Lecture 1, Pg 15 Position and Time l An example below: Question: What is happening in the two time elapse sequences shown below? What construction could I use to quantify it? Physics 207: Lecture 1, Pg 16 Page 8
Random facts about the cardiovascular system l 15 million blood cells are produced and destroyed every second l 60,000 miles of blood vessels in our bodies l Red blood cells live 120 days l Smallest cross-section: 30 micron diameter capillary l Largest cross-section: 1 inch diameter (i.e., aorta) Physics 207: Lecture 1, Pg 17 A preliminary step l Predicated on the need to know where and when? l Where requires a spatial reference frame and a system specifying position (magnitude, direction and units) l When requires a temporal reference frame (magnitude, direction and units) 1 2 3 4 5 6 6 5 4 3 2 1 Physics 207: Lecture 1, Pg 18 Page 9
A preliminary step l Predicated on the need to know where and when? l Where requires a spatial reference frame and a system specifying position (magnitude, direction and units) l When requires a temporal reference frame (magnitude, direction and units) time 1 2 3 4 5 6 (sec.) position 1 2 3 4 5 6 (meters) A particle representation Physics 207: Lecture 1, Pg 19 Different representations Pictorial time (sec) 1 2 3 4 5 6 position 1 2 3 4 5 6 (meters) x (meters) 6 4 2 Graphical displacement vector Algebraic 0 x = t (1 meter/sec) 2 4 6 t (seconds) Physics 207: Lecture 1, Pg 20 Page 10
A slightly more complicated example time 1 2 3 4 5 6 (sec) Pictoral x (meters) 6 4 2 Graphical displacement vector Algebraic 0 x = x 0 + v 0 t + at 2 2 4 6 t (seconds) meters/sec Physics 207: Lecture 1, Pg 21 Test your understanding Three motion diagrams are shown below. Which is (1) a dust particle settling to the floor at constant speed (2) a ball dropped from the roof of a building (3) a descending rocket slowing to make a soft landing on Mars? A. (a) is dust, (b) is ball, (c) is rocket B. (a) is ball, (b) is dust, (c) is rocket C. (a) is rocket, (b) is dust, (c) is ball D. (a) is rocket, (b) is ball, (c) is dust E. (a) is ball, (b) is rocket, (c) is dust Physics 207: Lecture 1, Pg 22 Page 11
Standard Quantities l Basic elements of substances and motion. l All things in classical mechanics can be expressed in terms of the fundamental quantities: v Length L v Mass M v Time T l Some examples of more complicated quantities: v Speed has the quantity of L / T (i.e. miles per hour) v Acceleration has the quantity of L/T 2 (Chapter 2) v Force has the quantity of ML / T 2 (Chapter 4) Physics 207: Lecture 1, Pg 23 Units l SI (Système International) Units: v mks: L = meters (m), M = kilograms (kg), T = seconds (s) l British Units: v L = inches, feet, miles, M = slugs (pounds), T = seconds l We will use mostly SI units, but you may run across some problems using British units. You should know how to convert back & forth. l Ask yourself, why do units matter? Physics 207: Lecture 1, Pg 24 Page 12
Recap l For Wednesday s class» Work on HW0, start HW1» Read Chapters 1 & 2 (through section 2.4) Physics 207: Lecture 1, Pg 25 Page 13