2009  2010 Syllabus
and Course
Expectations and the official
time
Honesty /Safety /Tardy/ClassComputer Use/Cell Phone policies
Walker1
& Walker3
websites
AP Physics and FAQ/practice AP problems and North Carolina Physics Curriculum
How Stuff Works! and How Things Work
November 2 
November 3 
November 4 
November 5 
November 6 


physics survey have you sent me your homework score...... (see email from today) (the maximum number is, I believe, 105 which includes 5 points for bring gravitylaw properties to class that day it was assigned) please send this today! it's supposed to be clear skies for the next 4 nights (including tonight); a great chance to figure out which way the moon goes around the earth! 
finally, the return of the second lab book sometime tonight (or early tomorrow) 
Amnesty
Day 3:30  5 pm ONLY if you have labs that werent graded, come IN PERSON with your lab book(s) and show me what lab did not get graded.... be familiar with the lab so that you can convince me that you did all parts tutorial help from physics teachers will be available most of the day schedule is posted on the physics floor 
do you know where? 
faculty are chained to their desks grading and writing comments 
what
we'll do in class 
practice
chapter 7 problems 

(always done before class) 
one new concept: power! STUDY the solution to last week's problems 9(20) and 9(28) on my bulletin board to see how to conserve momentum even if there are net forces acting 




inclass
presentation 
remember
the BAN on using dvat formulas on today's homework! 7(22) 

homework (by 5 pm) 
7(66, 24) the peekskillmeteoritehit car went on an international tour (Tokyo, Paris, Munich...) in the late 90s 











post one of your practice problems (or QUESTIONS (many of you need practice on the QUESTIONS!) from chpater 12 chapter 7 or chapter 9 by 8 pm today have you started practicing for the final exam? I hope so! you should be doing 3 problems  tht would mean about 45 minutes) each day (starting this past weekend).... one on each of the three kinds of problems we have done this trimester (you needn't pick new problems.... for practice, pick a problem that you did earlier.... because then you'll also have a solution from earlier in the year that you can compare to.... and don't worry, you won't rememner that you had done the problem earlier anyway!) 


October 26 
more gravity questions 
October 27 
October 28 
October 29 
October 30 



questions that arose in either C or D or maybe even both: if you were paying attention to the real world last week, you know that the discovery of 32 exoplanets was announced this brings the number of planets known outside our system to nearly 400 how did we discover these planets AND determine their mass  via Kepler's 3rd law  if we can't even see them? when (what day) does the earth move fastest around the sun? (block C doesn't care, but maybe block D does)... what is special about the earthtosun distance that day? (someone in) block D knew that the orbit period of most earth satellites is about 90 minutes.... how would we calculate that from Kepler's 3rd law? what does this have to do with the nonbook problem you turned in yesterday? how do artifical satellites (in movies) creat artifical gravity for its occupants? why is there a minimum size for a such a satellite that results in your apparent weight being equal to your normal earth weight? still unanswered in class..... 1) does the speed of a satellite (around a given star or around a given planet) increase or decrease as the satellite moves farther out? how do you decide? it should be pretty easy to calculate based on what we have done already.... a nice question for the upcoming final.... (if you want to show me your answer after you work it out, i will be happy to confirm....) 2) does the gravitational field increase or decrease as you go inside the earth? what is g at the earth's center? how do you know?.... here's a hint that will help you figure it out. let's say we want to find the gravity force on you if you are inside the earth at distance d from the center... (which is less than the radius of the earth dR_{E}).... what part of the earth's mass exerts a force on you? only the earth's mass that is closer to the center than you are! (i.e., only the part of the earth whose distance from the center is < less than d!).... if you assume the earth has constant density, you should now be able to figure out how g depends on d (if you want to show me your answer after you work it out, i will be happy to confirm....) 

a
REQUIRED experiment: at some time tonight (or tomorrow or the next night) check out the position of the moon in the sky..... then, tomorrow, or the next or the next night.... do the same thing (note the position of the moon in the sky) AT THE SAME TIME OF DAY as the first observation.... what will this tell you? the direction that the moon revolves around the earth! what the heck have you been doing at night for all these years?!?!?!? start experiencing life! 


what
we'll do in class 
start
our 3rd kind of problem..... 
work on Lab A11  
(always done before class) 
and have you noticed how many chapters we're covering this week? 9(1 up to  but not including example 91) then 9(5 up to  not including  example 95) then 9(4) what is momentum; when is it conserved? was momentum conserved in lab last friday? be careful.....! 
especially the example of the hail and rain 




inclass
presentation 
12(29) 
finish up the problem we didnt finish in class Monday the revised (to one dimension) example 96 master the 7 (or is it 8) step method 
9(17) 
9(13) 

homework (by 5 pm) 
read problem 12(59) after you're finished & suppose that you live on the earth's equator.... what would the rotation period of the earth have to be for your apparent weight to be equal to 50% of your true weight? 

& 9(28) 




labs A5, A6, A7AD, A8, A10 should all be completed (with conclusions written)... they will be handed in tomorrow by noon 









October 19 
October 20 
October 21 
October 22 
October 23 
weekend of
October 23 24 


teachers have a work day 

test on all of
forces (dvat's may be included of course), including force labs 

we do lab A10  
what
we'll do in class 
satellites, artifical and otherwise 
more
on satellites, orbiting, & Kepler's laws.... 
we do lab A10; there is a very short prelab put the data table in your lab book spread evenly across two facing pages 

(always done before class) 

after you returned last night things to know: 1) leftover from last friday: if gravity up at the space station is 9.5 m/s2, why are those astronauts weightless? 2) why is "microgravity" the dumbest word ever? 3) did they do a good job in following our forcediagram procedures in the three examples they did a) beginning at bottom of page 369 and ending in midpage 370? b) example 124 c) active example 121 what do all three examples have in common? 

know Kepler's laws (yes, as in "by heart") what (physics) is the 3rd law in disguise? (what about the other two?) (if you want to show me your answer after you work it out, i will be happy to confirm....) 
read the lab A10 lab handout 
still unanswered in class..... 1) does the speed of a satellite (around a given star or around a given planet) increase or decrease as the satellite moves farther out? how do you decide? it should be pretty easy to calculate based on what we have done already.... a nice question for the upcoming final.... (if you want to show me your answer after you work it out, i will be happy to confirm....) 2) does the gravitational field increase or decrease as you go inside the earth? what is g at the earth's center? how do you know?.... here's a hint that will help you figure it out. let's say we want to find the gravity force on you if you are inside the earth at distance d from the center... (which is less than the radius of the earth dR_{E}).... what part of the earth's mass exerts a force on you? only the earth's mass that is closer to the center than you are! (i.e., only the part of the earth whose distance from the center is < less than d!).... if you assume the earth has constant density, you should now be able to figure out how g depends on d (if you want to show me your answer after you work it out, i will be happy to confirm....) 
inclass presentation 
12(29)
will now be monday's show and tell.... instead, show and tell is the prelab for today's lab 

homework (by 5 pm) 








(that's A5, A6, A7AD, and A8) 





did you practice calculating with really big or small numbers on your calculator? did you waste time putting 3 or more significant figures into the calculator or did you save time (and avert mistakes) by using only 2? 
check the stray paper envelope for
YOUR papers.... there are sure a lot of them in there... which means
some people can't be tracking their homework averages.... yes, I know
who you are... put up 1 of your practice problems on the bulletin board, in preparation for the test tomorrow..... deadline 8 pm 


have
you looked at the syllabus (link at top of this page) lately? how many more chapters are scheduled to be done this trimester? how many days are left this trimester? 
October 12 
October 13 
October 14 
October 15 
October 16 




it's a
miniMonday 


what we'll do in class 
finish the friction lab: A7D; bring your lab book we do lab A8c, the acceleration of elevators 
cars 
deconstruct Newton's gravity law 
gravity problems 
lab practical !! bring your lab book; wear lab clothes; calculator, etc. required for entrance 
(always done before class) 

what forces did they leave out? in what directions? 
gravity is no longer down (necessarily) 


inclass
presentation 
6(47 & 48b) 
bring a list of the important features of Newton's gravity law 
12(16) (yes, a force diagram and net force equation, etc etc is still required, even though we have a new force) 

homework (by 5 pm) 
prelab to elevator lab due at 5 pm with the inclass presentation: 6(50) 

6(83) 

and yes, 12(14) still requires a force diagram, and a net force equation 12(21a).... yes, force diagram, net force equation, .... (see the trend?) the algebra can be either easy or complicated (depending on YOU!) for my sake, please make it easy) 

it should be ready to hand in if you STILL haven't had your prelab for A7D graded, did you leave me your lab book this past weekend? 






have you picked up The Way Things Work from the book room? (one copy per dorm room) 
1 week from today have you been doing enough practice? that will eliminate silly mistakes, such as a) wrong angle when breaking up forces into components b) missing subscripts on masses in multimass problems c) violating step 3 (which includes the interludes) of forcediagram procedures (this is an especially horiffic mistake) some excellent practice problems: 6(27, 75, 73, 67, 84, 90, 94) also 6(62, but also find the magnitude and direction of the acceleration while sliding) 6(40, except find the coefficient of static friction necessary to keep the masses from moving) 5(62) 
(THIS TIME.... I will only look at it once! be ready!) in person (by 5 pm.... please don't wait until the last hour)... problems 6(37, 38): a) find the acceleration of the two masses when the coefficient of kinetic friction of between the incline masa and incline is 0.10 b) find the coefficient of static friction necessary to prevent the blocks from moving 
October 5 
October 6 
October 7 
October 8 
October 9 







what
we'll do in class 
problem 6(11) & demonstration examples of static friction 
problems 6(7) and 5(44) 
lab A7 parts A and D 
horizontal circles: the plane! the plane! 

(always done before class) 
know the properties of static friction 


(horizontal circles!) circular motion KNOW the magnitude and direction of circular acceleration.... did they prove either/both of these? how? 
(vertical circles) 
inclass
presentation 
6(4)
but only the part about kinetic friction 
6(4) but only the part about static friction  6(10) 

homework (by 5 pm) 
& 6(2) 

lab A7 part A in lab book (yes, the one with A5 and A6; it's the only book you should have) prelab to lab A7 part D also in the same lab book 

6(79) 


by 8 pm: lab A6 poster (one side) due on the bulletin board (AND in your lab book): include 1) data table of ordered pairs 2) linearized graph with linear fit 3) 5 column matching table (the last two columns of the matching table are expected value of the fit parameters (slope & intercept) & % difference between actual fit parameters and expected fit parameters 4) conclusion 5) statement/signature by all participants that work was shared equally posters available by the black box 





finish the coffeecup problem meditate on the email I sent you 

forces test: wednesday october 21 
September 28 
September 29 
September 30 
October 1 
October 2 


teachers have classes, or worse, meetings 

enter lab A6 into your table of contents (same book as lab A5) 


what we'll do in class 
finish
problem 5(16); we've already done the force diagrams; come ready to write the force equations our first inequality problem, 6(22) 
lab A6 the cat picture, 6(26) 
the Garabage Gobbler & the wedged ball, 6(33) 

(always done before class) 

for those who didnt last friday: section 64 up to but not including example 66 
lab A6 we will be doing 2 different labs simultaneously (although each group only will be doing one) KNOW each of the 2 experiements (what's the independent variable? what's the dependent variable?) because you won't know which experiment your group is doing until midclass see more in lab block below 
section 5(5 and 7) 
know the properties and laws of KINETIC FRICTION.... warning: there may be parts that you might disagree with? & first half of the Guide to Perfect Force Diagram Solutions in case you want more copies.... Columbus Day soon approaching... they make excellent Columbus' Day gifts 
inclass presentation 
prelab
to lab A6 done in the lab book for the prelab, we don't want you to do the full sevenstop forcediagram method..... instead, try to arrive at the solution by answering the questions in the prelab.... we think it should take 5 minutes 
5(51) 

homework (by 5 pm) 


5(6 part a only).... assume that the parachute no longer exerts tension on the parachutist (because the chute hit the ground before she did) during the deacceleration by the ground this is our first problem that combines dvat with a force diagram problem (since you are probably doing the dvat first, remember the rules for definition of positive for force problems... and you may NOT change positive in midstreamproblem) 

+ 6(72); our first forcetriangle problem... the only force diagram, net force equation, etc. is for the rope, right? but be careful of the question it asks 



& put data table in lab book across two ENTIRE pages 
1) what quantity is your group going to plot on the horizontal axis? 2) what quantity is your group going to plot on the vertical axis? 3) what are the math and physics equations that will describe your fit? 4) what is the numerical value of the independent variable (the quantity on the horizontal axis) of your first run? 



have you picked up your 4 book cover sheets from my black box if your book doesnt have them? 

have you finished the cat picture
(good algebra practice), 6(26) and the wedged ball (good trig practice), 6(33) problems ?? 
pages for september
2009
pages for
august
2009