Class 10

UPDATE (TUE 3:45pm):  There is a lot going on at this point, so here is a list of what you have to do before the class on Thursday.

1.  Read everything on this Class 10 blog and print the attachments (including the new one [in red] at the end of this red list.)  PLEASE BRING YOUR SCIENTIFIC CALCULATOR TO CLASS.

2.  Decide on eight projects from the handout from Sun 6:00pm that look interesting to you.  THEY ARE ALL GOOD so don't agonize over them and worry about what they mean.  Just pick eight of them that look like they might be interesting.  Then mark each one with a letter (A, B, C, D, E, F, G, H).  A is your first choice and H is your 8th choice.  The reason to do this is that each student will draw a number from 1 to 8.  The student with the 1 goes first to pick a project, 2 second, etc. So when your turn comes up, your highest choices may already be taken.  If your A and B choices are taken, you will immediately select the next letter (C).  Otherwise we are going to spend the whole hour with kids trying to figure out which project they want.  If you can't select your project immediately when your turn comes up, I'll go to the next person and you'll drop back until you are ready.  These are all great projects and you will do fine and have fun no matter which one you get.  I wish I had time to do all the projects by myself, so I could have a lot of fun, too!

3. Please make sure you bring all 3 handouts to class.  Thank you!

HANDOUT FOR THE CLASS MATH REVIEW:
https://sites.google.com/site/yhbscience/Class10.CLASS.recording.sheet.rev2.docx?attredirects=0&d=1


4. Please don't forget to do Homeworks 7 and 8.

HANDOUT (Sun 6:00pm):  Here is the handout for class.  Please read before class.  :)  Thanks.

https://sites.google.com/site/yhbscience/Class10.Science.Projects.using.Gravity.rev1.docx?attredirects=0&d=1

HOW TO DO HOMEWORK 8 and 7 and get 100% right on both.  (Fri afternoon 5:40pm)\
To get 100% you have to do exactly what the steps below say to do.   (The four people who turned in HW 7 yesterday -- thanks for being on time --  can print out a new copy and resubmit HW 7 to get 100%)  If you want to learn more (and get a higher grade), you should resubmit using these instructions.  :)
      Yes, the instructions are very long, but that's because I am trying to explain very carefully, so you can understand (I hope!).  We don't have enough time in class to explain everything.

STEP 1.  Learn how to do a square and a square root on your calculator.  Get someone to show you how.  Then do these two tests to see if you really can do it:
-Find the square of 5.23  ANSWER 27.3529
-Find the square root of 85.333  ANSWER 9.2376
If you did not get both of these two answers right (ignore small differences in the last digit), go to the website

http://www.csgnetwork.com/squarerootsquarecalc.html

This is guaranteed to do squares and square-roots correctly.  PLEASE USE THIS FOR ALL SQUARES AND SQUARE-ROOTS until you learn how to do them on your calculator.

HOMEWORK 7

First, write your name on all three pages.  Then staple them together.

NOW, you can fill in the two columns for problem 1. (The square-root column wants the square-root of the square (in the middle column) that you just computed - NOT the square-root of the number in the first column.  Just like my examples on the homework showed.)

STEP 2.  The first blank says "N = ____" .  What is N?  N is how many numbers you have.  In the EXAMPLE given in the HW, you had four numbers, (1,2,3 and 4) so N = 4 there (as the EXAMPLE shows).  Now you have five numbers (1,3,5,7,and 9) so N = 5

STEP 3.  Then it says "first ADD them"  If you can't add the numbers in red above, please ask an adult.       whenever it says "PLEASE ASK AN ADULT," Please ask her/him to read this blog so they will know all the steps I am giving you.

STEP 4. Next, it says "Then DIVIDE by N" If you can't divide the sum of the red numbers by 5, please ask an adult.

STEP 5. Then it says "The MEAN, M =  _______ "  This is what you got when you finished STEP 4.  Just copy it here.

STEP 6.  3(a)  asks you "Whose measurements are more accurate?"  The numbers that are more accurate will be closer to each other.  Look at your numbers and then look at Cheezy's numbers.  It will be obvious which numbers are more accurate (closer to each other).  If you don't understand, please ask an adult.

Then it asks "Whose SD should be smaller?"  Did you read the instructions to problem 3. right above the questions?  It says "The smaller the SD is, the more accurate the numbers!!"  So whoever you said had the more accurate numbers will have the smaller SD (even though you don't know what the value of the SD is - you know it has to be smaller!).  Both of your answers have to be the same, you can't answer YOURS for one of the questions and CHEEZY'S for the other question.

STEP 7. Now we compute means and standard deviations.  NOTE - in the SD equation it has N/N-1.  It has to mean N/(N-1).  If it meant (N/N) - 1  that would be (1) -1 = 0 and all SDs would be zero!  So if you are working  with five numbers, N = 5.  Then N/N-1 = 5/(5-1) = 5/4 = 1.25.  That's where the 4 comes from.  If you had  26 numbers (so N = 26), the fraction would be 26/25 = 1.04.  Got it?

STEP 8.  for Your DATA,  N = 5 because you have five numbers (in 3(a)).  Then you copy the five numbers from 3(a) into the five blanks under NUMBERS.  Then you find the squares of each of those numbers, and write the answers in the five blanks under SQUARES.  Here is the answer to the first one; you do the rest.  NUMBER = 16.1  =>  SQUARE =  259.21 (exactly)  NOW CHECK!! by taking square-root of 259.21:  You get 16.1 back.  THIS PROVES YOU ARE RIGHT!! Are you checking all of your answers before you turn in your homework??

NOW Steps 9 and 10 apply to both the column labelled NUMBERS and the column labelled SQUARES

STEP 9.  For SUM you add the five numbers in the column above.

STEP 10. For MEAN you divide the SUM by 5.

STEP 11.  FORGET about the equation for SD and leave the answer blank (unless you want to try it).  Just go to the website I gave you:

http://easycalculation.com/statistics/standard-deviation.php

In the box above "calculate", type in the five numbers from the NUMBERS column with commas between the numbers, and then click "calculate".  On the line in the homework where it says "As a check" copy the program's result for Mean (Average) into MEAN = ______________  and the results for Standard deviation into SD = _____________.
You are finished this part.

STEP 12.  Repeat exactly the same steps (Steps 7-11) for CHEEZY'S DATA.

STEP 13.  Answer 3(d) based on your new information.  First answer the second part (Whose SD is smaller?) using the new results you just calculated for YOUR SD and CHEEZY'S SD (from the two lines beginning with As a check...)   After you check whose SD is smaller, you can answer the second question in 3(d).

Then back up a line to answer the first question "Whose measurements are more accurate?"  Remember that both questions must have the same answer, so circle the same one you circled below,

STEP 14. Now for Part 4 (at the end of it).  Copy YOUR SD and N from 3(c) into the two blanks.  To calculate SDM, just divide SD by SQUARE-ROOT of N.  Since N = 5, this gives you square-root of 5 = 2.2361 (CHECK that of course)  2.2361 squared = 5.0000.  Yes, it checks!!
So, SDM = SD/2.2361 and put it in the blank space.  I don't mean write "SD/2.2361" in the blank, I mean substitute in the numerical value of SD you already calculated, and then after you do the numerical division, put the numerical result in the blank.  Got it?

Repeat STEP 14  exactly to get the SD, N and SDM below where it says " and for Cheezy's results"  You should now copy Cheezy's five measurements from 3(a) and then do the rest of the stuff in STEP 14.

***  You are finished Homework 7 ***

HOMEWORK 8    OK, let's do it!  If you learned how to do HW 7 according to my step-by-step instructions, HW 8 should be pretty easy.

Start by writing your name on all 3 pages and then you can go to STEP 1.

STEP 1.  The first thing is to write on the HOMEWORK sheet the data from EXPERIMENTs (EXPs) 1, 2 and 3 in the NUMBERS columns. To do this, you need to click on (and PRINT OUT) the attachment at the bottom called PENDULUM EXPERIMENTAL DATA
- Transfer the nine (POP QUIZ: WHAT DOES N EQUAL?) numbers (first number is 2.011, last one is 2.032) from EXP 1 on the attachment to the "NUMBERS for T(s) column" of EXP'T 1 in HW 8.  Then transfer the nine numbers from  EXP 2B (2.014 to 2.014) to EXP'T 2 in HW 8.  Then transfer the nine numbers from EXP 3 (1.424 to 1.431) to EXP'T 3 in HW 8. (Don't worry about about EXP or EXP'T, they are both abbreviations for EXPERIMENT)  (Don't worry about about EXP 2A data -- I did 2A and you did 2B and the results are close: mean = 2.00733 (me) and 2.01122 (you guys).  The difference in your results and my results  is LESS THAN TWO-TENTHS OF ONE PERCENT.  REMARKABLE!!

STEP 2.   Now, you fill out the rest of Part I exactly the same as in HW 7.  At each step of the way, you can check your results against mine from the attachment.  IF you can't get my results, then yours are wrong (I think  :)  ).  So just copy my results where needed & write "COPIED"  At least you will have something to think about.  DON'T FORGET TO TRY THE TWO WEB CALCULATORS (For Square and Square root, and for mean and standard deviation) GIVEN ABOVE BEFORE YOU COPY.  BUT DON'T WORRY IF YOU HAVE TO COPY, JUST THINK ABOUT YOUR ANSWERS & MINE AND SEE IF YOU CAN FIGURE OUT WHY MINE MAKE MORE SENSE.  Ha Ha.

STEP 3.  PART I.   Ratio of bob masses = 69.0 g/19.6 g = you tell me :) <-- answer 1
                Ratio of mean periods = 2.01122 s / 2.01256 s = you tell me :) <-- answer 2
Now do "A change in bob mass...." (put ans. 1 in 1st blank, and ans. 2 in 2nd blank).
NOW you have to think a little.  See the first 2 numbers in the EXAMPLES  ?  If your mratio = mass ratio (ans 1) is near 4 (3.5 would be considered near 4 because it is almost 90% as big as 4) and your Tratio = period ratio (ans 2) is near 1, then you choose "none" - it means the period doesn't change when the mass changes.  If you got something near 4 and 4 you would choose "proportional",  and so on.

The others are the same idea.  For your home experiment (by the way, I found that dental floss makes a great string for pendulums -- it doesn't break), when it says "home 2" and "home 1" it means the 2nd home experiment (90 degree swing) and the 1st home experiment (10 degree swing).  90 degrees means the string starts horizontal.  To measure the 10 degrees, you can use the angle protractor in the handout I gave you (see blog) or you can use tan(10 degrees) to figure out how far to pull the bob sideways when you start.  For a 20 inch string, you have to pull it 3.5 inches to the side, then let go.  If you want to do it in cm, then for a 50 cm string, you have to pull it 9 cm sideways and let go.

HAPPY SWINGING!!

   PENDULUM DATA. (Thu night)  Here are four data sets.  I did two (Expt 1 and 2A) and you did two (Expt 2B and C).  Your measurements were EXCELLENT!  Congratulations.  You can tell by how small your SD was -- and this is what tells how accurate the numbers (measurements) were.  Your numbers were accurate to 0.013 seconds.  That means 13 thousandths of a second!!!   [My two runs (1 and 2A) were accurate to 0.010 and 0.013 seconds.]
   This should help you check your homework.  Some of you need to ask somebody how to do a square and a square-root on your calculator.
   When you do the experiments at home this week to determine the effect of different swing angles, it will be better if everybody uses the same string length, so let's all make the distance from the pivot point to the center  of your bob = 50cm (L = 50cm), just like your last experiment in class.  To convert cm to inches, divide by 2.54.  This will give you 19 11/16 inches (almost 20 inches).  Ask an adult to check this out before you do your experiments.

https://sites.google.com/site/yhbscience/Class9.PENDULUM%20EXPERIMENTAL%20DATA.docx?attredirects=0&d=1

-Mr Frank

Class 9

UPDATE: Wed 8:45 PM - HERE IS rev 3 HW 8 due Thu Mar 13.  PLEASE bring to class TOMORROW to record the pendulum data we'll be taking. Sorry it's so late.  THANKS!!

https://sites.google.com/site/yhbscience/Class9.Homework8--Analysis.of.Pendulum.Experiments.rev.3.docx?attredirects=0&d=1

UPDATE: Mon 7:45 PM  - Here is the homework due on Thursday (Mar 6). The standard deviation material may be a little hard to understand, but each step required is exactly the same as the EXAMPLE given.  If you can't figure out how to check your mean and standard deviation results by using your scientific calculator, try a web-based calculator like

http://easycalculation.com/statistics/standard-deviation.php

If you still have problems, then don't worry.  But make sure you do it using the techniques I showed you in the homework.  In class on Thursday, we'll do pendulums.

https://sites.google.com/site/yhbscience/Class8.Homework7A--Mean.and.standard.deviation.docx?attredirects=0&d=1

UPDATE: Sun 11:42 AM  - Midterm grades have been emailed!

-Mr. Frank

Class 8 - Please read before Feb 26

STUDENTS:  Please read before Feb 26.  Here are some things to help you study for the exam on Feb 27:

1) Copies of the solutions to Homework 5, Homework 6-1, and Homework 6-2.

NOTE - The exam will be easier, but try to understand the difficult parts in these homework problems as much as you can.

https://sites.google.com/site/yhbscience/Homework.5.JPG?attredirects=0&d=1

https://sites.google.com/site/yhbscience/Homewk.6-1.JPG?attredirects=0&d=1

https://sites.google.com/site/yhbscience/Homewk.6-2.JPG?attredirects=0&d=1

2) UPDATE MONDAY 3:07 PM:- The final Study Guide (7B) and Equations (7C) handouts are now on the blog for Class 7.  For specificity, they are both dated 2/18 (B was at 8:39 PM and C at 8:45 PM)

Check them both out and if the date and time at the top of the handout are later than the one you have, please print them out and take them to the exam in your binder.  Any changes are minor, but you should take the final versions, anyway

Best wishes for the exam -- it's easier than the homework.  Don't forget to bring scientific calculator, reference binder (with notes, if you want them), 2 pencils and eraser! There will be no sharing of calculators, binders, notes or anything during the exam.

-Mr. Frank

Class 7- please read before Feb 20

STUDENTS:  Keep up the great work, everyone!!  I hope you like the new homework style!
   We are starting something new in class.  There will be a five-minute POP QUIZ at the beginning of the next class. The purpose of these short quizzes is to encourage students to be in the classroom on time, to make sure you are reading the entire blog, and to encourage you to learn the material in the course.
   The quizzes will be started at 2:00 and collected at 2:05, so please be in your seat at 2:00.  Thanks!
   For Pop Quizzes no reference materials are to be used.  Future Pop Quizzes will not be given every class and they will not be announced ahead of time.  They will count towards your course grade.  If you remember what the blog says and follow the instructions, you should have no problem because the questions will be pretty easy.
   Also, please watch the 3-minute YouTube video indicated below.  The video shows you how to to use the Microsoft Office program EXCEL to plot a graph of data.

http://www.youtube.com/watch?v=oZAZj7NIkic

   Make sure you remember the basic steps of how to use Excel to plot the graph.  The best way to do that is actually to use EXCEL if you have access to it* and do the steps shown in the video.  It's a lot of fun!
   After you start EXCEL, type in your practice data and then drag a box around it.  On my computer (Windows 7) you have to click on the INSERT tab and then click on SCATTER.  Your graph with the data points should pop right up!

* If you don't have EXCEL, just follow along and pretend you are typing and clicking everything.  I highly recommend this program, otherwise you'll have to download another plotting program, buy one, or make all your plots by hand.

STUDENTS:  Your first EXAM (test) will be on February 27.  It will cover the first 6 classes-- everything up to and including acceleration.  Every student should bring a scientific calculator, their up-to-date Reference Binder,  2 pencils, and an eraser.  I'm being so specific because I want everyone to do as well as possible on the exam.

There is NO HOMEWORK ASSIGNMENT on this (Class 7) blog that would be due on Class 8, because Class 8 is your first exam, and I want you to have extra time to study for the test.

Here is a Study Guide for the exam.  Everything on the exam will be mentioned here.

https://sites.google.com/site/yhbscience/Class7.Handout7B--Review.Guide.for.First.Exam.rev3.docx?attredirects=0&d=1


All equations needed for the exam are on this sheet.

https://sites.google.com/site/yhbscience/Class7.Handout7C.Equations.Exam1.rev2.docx?attredirects=0&d=1

Please do not miss the exam next week, and don't forget that Homework 6 is due this Thursday.

Thank you!

-Mr. Frank

Class 6

PARENTS:     Please check email for solutions to HW 4.  Thank you!
PARENTS:     Students taking Physical Science will each need a personal scientific pocket calculator (or an APP on smart phones; one per child) during tests that are capable of doing the functions we are using.  Experience has shown that it would be too disruptive for students to be passing calculators back and forth during a test.

An example of a powerful scientific calculator is the Texas Instruments TI-36X Pro.  The best price I could find on Amazon.com was $19.81 (for Prime members only).  But yesterday, I bought one ON SALE at WALMARTS (on Winchester near Sam's Club) for $9 !!  They had four more on the wall (HOME/OFFICE).

(If you can't find this model, there are others available for under $9 -- just make sure they have

 x², square-root, sin, cos, tan and inverse trig functions (invsin or sin^-1, and same for cos and tan)

For families for whom this would be a significant financial burden, please contact me, and Kay and I will try to help.

Thank you for your help and cooperation!

STUDENTS:  

Each student must bring his/her reference binder to class this Thursday.   See the Class 5 blog for detailed instructions.

Also, please don't forget to go back to Class 5 and get the download with the 4 triangles that lets you prove the Pythagorean Theorem with no math!  You're going to love it when you figure this out (or after I show you, if nobody gets it).  I'll bet somebody figures it out -- we have a very smart class!!  :)

Homework 6:

https://sites.google.com/site/yhbscience/Class6.Homework6A--Simplified.positional.information.docx?attredirects=0&d=1

- Mr. Frank

Class 5

Homework --

https://sites.google.com/site/yhbscience/Class5.Homework5A--Units%26positional.information.docx?attredirects=0&d=1


Binder Instructions --

https://sites.google.com/site/yhbscience/Class5.Handout5B--Instructions.for.your.binder.docx?attredirects=0&d=1


Fun Challenge --
Can you prove that  C² = A² + B² in a right triangle without using any math?  Here are the materials you need to do it!  I read that this was discovered by a high school student in Indiana in the 1930s!!  Happy Trails to you until we meet again! 

https://sites.google.com/site/yhbscience/Prove.Pythagorean.Theorem.with.NO.MATH.docx?attredirects=0&d=1


-- Mr. Frank

Class 4

Greetings, Parents and Students.  Keep up the good work!!  In Class 4 we are going to go into the practical uses of vectors.  We'll also do a short but educational play with two student actors!

First, I want to outline a way for every student to improve their homework understanding and grades.  How do you know if your answer is right?  Many people don't worry about that, or they do the problem again to see if they get the same answer.  Neither way is very good.  If you repeat the problem, you may have the same misunderstanding or make the same error again, so repeating does not tell you if you are right.

^{I have prepared a carrying card for you that outlines three good ways to check your work.  If you use any of them and get the same answer, your confidence in being right should go way up. You'll be surprised at how much fun checking is.  Click this link:
https://sites.google.com/site/yhbscience/Class4.Carrying.Card.for.Checking.Problems.docx?attredirects=0&d=1}

A QUESTION:  A parent asked me how we measure the vector angle.  We start the angle at the x-axis and swing around counterclockwise until we reach the vector.  Assuming that the x-axis direction is east (E), we would get the following angles (in degrees): E = 0, NE = 45, N = 90, NW = 135, W = 180, and so on.  By the time we get around almost full circle, we have SE = 315 and E = 360 (or 0 again).  Sometimes, to avoid large angular numbers, we start at the x-axis and go clockwise, but change the sign of the angle!  Sometimes pocket calculators do this.  This gives: E = 0, SE = -45, S = -90, SW = -135, etc.

NOTE - To make matters more "interesting," sailors and pilots don't do it like scientists and mathematicians. They start at N and go clockwise !!  Oh me, oh my!

Here's Homework 4.  Best wishes!  Please don't forget to bring it to class.

https://sites.google.com/site/yhbscience/Class4.Homework4--Summary.of.Classes.1.to.4.docx?attredirects=0&d=1

UPDATE: 1/30  8:15 AM  If you see this in time, please bring to class.  If not, I will have extra copies.

https://sites.google.com/site/yhbscience/Class4.Handout--Units.of.Physics.docx?attredirects=0&d=1

UPDATE: 1/30 1:00 PM  I know this is too late to bring to class.  Please make sure you download it.
https://sites.google.com/site/yhbscience/Class4.Handout--Solve.any.vector.problem.docx?attredirects=0&d=1