Section

  • activity Monday:  find a value for g using available equipment

    HW due Tuesday: report a value for g from your experiment

    HW due Wednesday:  Bring solution to the problem assigned on Tuesday.  

    Thursday: we will measure moving objects: fan cart, ball, falling filter, etc

    HW due Friday:  Read the entire Wikipedia entry for "physics" and be prepared to answer questions.  Don't memorize dates and names, but absorb the main themes

    HW due next Tuesday: text problems chapter 1:9,19 (difficult), 22, 25, 53 and 1 other 2-dot problems.  

            also Tuesday: individually, use loggerpro to show me displacement, time, velocity, and acceleration for each movement

    HW due next Friday: give a 4 minute tour of your section of lab equipment

    Objectives for this week:

    • Understand the goals of this course

    • Explain how the pace and approach in the course will differ from last year

    • Apply your deep and long dormant knowledge of measurement and kinematics

    • show that you can be independent learners

    https://imgs.xkcd.com/comics/laws_of_physics.png

  • Due Tuesday: text problems chapter 1:9,19 (difficult), 25, 31, 43 and 1 other 2-dot problems.  also Tuesday: individually, use loggerpro to show me displacement, time, velocity, and acceleration for each movement

    in class: we will drop things and record their path with loggerpro.

    Due Wednesday: Hand in ramp analysis as assigned on Galileo Lab 

                in class you will design and conduct a lab to find g with a free falling object.

    Due Thursday: 2: p-3, 5, 15, 19, 27, 37, 41

    On Thursday: ARRIVE EARLY, 12:45 PM TO START LAB: bring prework assignment see attached lab "Find g as Galileo did"

    Due Friday:  Hand in short analysis of Tuesday Ball-drop demo as a HW problem; report the settings you used in Loggerpro, and carefully report the set up.  handwitten is fine.  Include a sketch of each set up.  The writing should be about a page long, and attach your loggerpro graphs that gave you acceleration.

    Also due Friday: give a 4 minute tour of your section of lab equipment

    Due next Monday: bring g data from lab.  2: P-53, 55, 63, 69, have latest Loggerpro available at home computer.  See tools for download instructions.

    Due  next Friday:  Lab 1 (galileo) Report due: 2 page memo, including photo, table of data (you must process and display data using Excel), sketch showing dimensions, propagation of error, comments on results, and suggestions to improve.

     Points:

    • Detail how calculus adds to our def’n of velocity and acceleration
    • Be able to determine v or x from an equation of a
    • Interpret classic plots relating x, v, and a as fct of time
    • Assess recall of motion graphs through review activity (5to5 p 80)
  • I've posted a correct answer key to ODD problems in FILES; some of your books may be wrong in the solutions appendix.

    Due Monday: bring g data from lab 1.  2: P-53, 55, 63, 69, have latest Loggerpro available at home computer.  See tools for download instructions.

    Due Tuesday:  Barrons chapter 2, MX exercises 3,4,6,7 and FR 2,3,4 (As I said, you need to purchase Barrons Study Guide 4th Ed.  Bring me $15 today and I will order one for you)
    Also due Tuesday: give a 4 minute tour of your section of lab equipment

    Wednesday:  Hand in short report of Ball-drop lab 1 as a HW problem; report the settings you used in Loggerpro, and carefully report the set up.  handwitten is fine.  Include a sketch of each set up.  The writing should be about a page long, and attach your loggerpro graphs that gave you acceleration.

    Due Thursday: 3: Q-7, 9; P-35, 44,  and do two 2-dot problems of your choice, and data analyzed from Lab3 for discussion  

    Thursday: evaluate and test next steps in Galileo ramp lab.

    Due Friday:  Lab 1 (galileo) Report due: 2 page memo, including photo, table of data (you must process and display data using Excel), sketch showing dimensions, propagation of error, comments on results, and suggestions to improve.   I have posted the grading rubric in FILES.  I will follow this when I grade the lab

    Due Next Monday:  F = G M1 M2/r        This is the equation for a model that describes the dollar volume of trade between two countries, F, as a product of a constant G, the M (size of economy) of each country) and the inverse of the distance, r, between the countries.    Does the form look familiar?  Find a physical reason why the denominator is r and not r2.

    read http://what-if.xkcd.com/62, and then find by web research a relationship between sphere size/mass and terminal velocity in air.  Specifically, you should be able to show how big a spherical balloon must be to slow your terminal velocity to 10.m/s.  See figure below.  This problem is not for fun, there are good answers and you are expected to find one using accepted physics.  Why?  Because understanding drag through air is an important part of this year, and independent learning is a critical part of your life.

    next week: we'll do lab on Go Motion and Video analysis with coffee filter

    * goals for this week:

    1. Detail how calculus adds to our def’n of velocity and acceleration
    2. Be able to determine v or x from an equation of a
    3. Interpret classic plots relating x, v, and a as fct of time
    4. Assess recall of motion graphs through review activity (5to5 p 80)

    figure 1.  Sketch of person mass m falling at terminal velocity vt using spherical balloon of negligible mass.

  • Due Monday:  F = G M1 M2/r       This is the equation for a model that describes the dollar volume of trade between two countries, F, as a product of a constant G, the M (size of economy) of each country) and the inverse of the distance, r, between the countries.    Does the form look familiar?  Find a physical reason why the denominator is r and not r2.

    read http://what-if.xkcd.com/62, and then find by web research a relationship between sphere size/mass and terminal velocity in air.  Specifically, you should be able to show how big a spherical balloon must be to slow your terminal velocity to 10.m/s.  See figure below.  This problem is not for fun, there are good answers and you are expected to find one using accepted physics.  Why?  Because understanding drag through air is an important part of this year, and independent learning is a critical part of your life.

                          In class, we will learn about drag of the filter (powerpoint slides)

    Due Tuesday:  2:MX 5,8 and FR 1,5

    Due Wed: 4 P-1,8, 9, 15, 17, 21  .Lab 3: freefall with Go Motion and Video analysis with coffee filter.   Refer to my discussion of drag and the physics of drag

    Thursday:  RETREAT

    Due Friday: RETREAT

    Due next Monday: 4: P39, 65, 63, 67, 107a, show the loggerpro analysis of all of your data in a table of terminal velocities (for the filters).  Turn it in (I'll give it back).

    Due next Tuesday.  bring your terminal velocity data plotted in Excel to find n and k.

     Points

    • Be able to solve problems in ijk vector notation
    •  Be able to identify parabolic relations and recognize parabolic motion
    • Be able to identify sin/cos relations and recognize circular motion
    • Be able to identify relative motion and solve in vectors

    galileo (Gal)

    the CGS unit of acceleration. One galileo is an acceleration of 1 centimeter per second per second (cm/s2). This unit is used by geologists, who make careful measurements of local variations in the acceleration of gravity in order to draw conclusions about the geologic structures underlying an area. These variations are typically measured in milligals (mGal). One Gal is approximately 0.001 019 7 g, where g is the acceleration of gravity, so a milligal is a very small acceleration, about 10-6 g. The name of the unit honors the Italian astronomer and natural philosopher Galileo Galilei (1564-1642), who proved that all objects at the Earth's surface experience the same gravitational acceleration. To avoid confusion with the symbol for the gallon, and to conform to the usual metric style, the symbol for this unit should be Gal rather than gal.

    Hey remember that cool cartoon on the Higgs?  Here's one on gravity waves, which were discovered last year.. http://www.phdcomics.com/tv/?v=4GbWfNHtHRg 

    And a reward for those who read all this entry: 

    www.youtube.com/embed/2rjbtsX7twc?list=UUTev4RNBiu6lqtx8z1e87fQ

  • the answer key to odd problems is posted in FILES.

    Due Monday: 4: P39, 65, 63, 67, 107a, show the loggerpro analysis of all of your data in a table of terminal velocities (for the filters).  Turn it in (I'll give it back).

    Due Tuesday: for review: 1. What launch angle will give R = hmax in a projectile motion "on the level" cannon;  2. What car velocity will allow a banked turn of 90o for a given radius, m, and μ?  3. What turn bank angle is necessary for a frictionless track for given r, v, m of car? 

    Due Wed: 5: Q-2, 4, P-12, 53, 71  (always bring Barrons to class)

    Due Thurs: show completed graph of F vs vn; complete all parts of AP-C Mechanics 2010 FR1 found here:    http://apcentral.collegeboard.com/apc/public/repository/ap10_frq_physics_c_mech.pdf.

    Due Friday:  turn in Barrons FRQ1 p 100. choose AP FR problems that have kinematics and/or force problems.   Do a total of 6 letter parts.

    Due next Monday: Exam 1, up through chapter 5

    some optional practice for the exam: 

    1. (10 points)   I drop a bowling ball of 5.4 kg from a tall cliff, and it reaches terminal velocity according to this equation for speed:
                          v = 850 (1-e-7.5t
      where t is time in seconds, and v is in m/s
      1. What is the terminal velocity?
      2. What is the distance travelled by the ball before it reaches terminal velocity?
      3. How much heat energy is dissipated by the ball before it reaches terminal velocity?

    A comment on report writing:

    • I'm raising the bar on your writing. We will do a bunch of reports of various types, and you will graduate from this class quite comfortable with writing good lab reports. That is my goal. So far I can see that reports and writing need some work, and I will hold the standard high.
    • Why?  Because convincing others that you know what you're talking about is of key importance. And most of your serious communication will be written.
    • A few common issues I see:
    • 0.  Narrative writing for reports means sentences and paragraphs.  It is telling a story with words.
    • 1. define any variable you introduce. e.g. Fg = the force of gravity on the puck; Θ is the angle between the table and the horizontal.
    • 2. any title for table or figure is a description of what is included. "Figure 1. Photo of sloping table with puck and detector in place"
    • 3. Learn how to make greek symbols and super and subscripts. It's not hard; don't use s^2 in place of s2
    • 4. Look for effects or results beyond those required. Show some curiosity. The world loves curious people.
    • 5. Always give a suggestion for improvement. You are being paid to think and make things better. Show that you have learned from your efforts.
    • 6. Take care when you write.   It requires 45 min for me to write a memo.  It probably will require you 2-3 times that long.  

  • Due Monday:   Exam 1 in class.  it will cover through chapter 5

    Due Tuesday:  I will hand out and we will discuss Lab on Projectile Motion  6: P-60, 68, and a 3-dot problem of choice; Barrons chapter 4 MX 1-5.  

    due Wed: 6: Q1,3,5 P-19, 23, 59 .  

    due Thursday:   Exercise in linearizing... that was handed out:  Complete parts 1-4

    due Friday:     Barron's 4: mx 6-8, fr 2,3   

    Due next Monday:    We will perform the projectile motion lab.   
    A car driver going at some speed v suddenly finds a n infinitely wide wall at a distance r in front of her. Should she apply brakes or turn the car in a circle of radius r to avoid hitting the wall?  You should assume there is a constant coefficient of friction with the ground.  Note: you have enough info and there is a definitive answer.  It should take about 3 lines of calculation.

    Due next Tuesday:  do AP 2000 Mech 3, and ignore the inertia of the pully    1. What launch angle will give R = hmax in a projectile motion "on the level" cannon;  2. What car velocity will allow a banked turn of 90o for a given radius, m, and μ?  3. What turn bank angle is necessary for a frictionless track for given r, v, m of car?   

    Next wednesday:  chapter 7: P-3, 5, 7, 9, 11

    Optional challenge that no one has every really tried to solve: find the function of the line defined by the outer envelope of motion of a given projectile cannon over all possible angles. look at this physlet and vary the angle from horizon to horizon to see the "envelope".    http://phet.colorado.edu/en/simulation/projectile-motion

    We'll look at the amazing Diavolo in class.

    activities: Quiz and practice 5:P-72 a,b and Problems 1,2 of Patel p39 (look under files)

  • Due Monday:    We will perform the projectile motion lab.   
    A car driver going at some speed v suddenly finds a n infinitely wide wall at a distance r in front of her. Should she apply brakes or turn the car in a circle of radius r to avoid hitting the wall?  You should assume there is a constant coefficient of friction with the ground.  Note: you have enough info and there is a definitive answer.  It should take about 3 lines of calculation.

    Due Tuesday:  do AP 2000 Mech 3, and ignore the inertia of the pully    1. What launch angle will give R = hmax in a projectile motion "on the level" cannon;  2. What car velocity will allow a banked turn of 90o for a given radius, m, and μ?  3. What turn bank angle is necessary for a frictionless track for given r, v, m of car?   

    Due wednesday:  chapter 7: P-3, 5, 7, 9, 11 

    Due Thursday: none Lab 4, projectile motion, video data analysis is due.  The video files are in j: drive, and you should confirm the launch velocity with the high speed video (210fps)

    Due Friday: 7; P-19, 23, 27, 29, 35.

    Due next Monday: finish the data analysis for the projectile motion lab
    AP problem 2009 Mech 1; 7: P-45, 47

  • This section

    Due Monday:  AP problem 2009 Mech 1; 7: P-45, 47

    Due Tuesday: velocity data for the lab; show me all the range data and all the speed data.

    Due Wednesday: 8: P-6, 23, 25, 27, 28; Choose one AP problem from the AP website that requires Energy for solving and be prepared to present to class  

    Thursday and Friday:  CONFERENCES

    Due next Monday: 8: Q 6-9; P-34, 40, 84;    practice in class 2000 M2