I have gone through the 1-D Test and have the following impressions… -Good first test -A lot of silly mistakes (having the correct equation written down but not getting the right answer, switching accelerations from Stan Speedy to Kathy Kool, [...]
If you find yourself a little confused about angular dynamics, feel free to check out the lessons from my close and personal friend, Dr. Walter Lewin…
Some of the things in these videos may be a little over your head but for the most part, he goes over the same things we go over. It is sometimes helpful to hear another teacher talk about the same topics…the other teacher may talk about things a different way that makes more sense to you.
As I was walking around the downtown area this weekend I noticed that the area next to the aquarium with the water jets is open again (and it has an awesome place to play in the water…I wish I was 4 again…). As I walked down to the water jets that shoot out into the river (next to the Market Street Bridge), I wondered to myself…”hmmm…I wonder what velocity those are shooting with”.
WIth that being said…we are going to have a little competition that will help you remember some of your old Physics stuff from the beginning of the year. I want you to convince me what the velocity of each of the jets is. You will receive extra points on your lowest test grade for this. To determine the number of points you will get I will use the following formula…
The person who does the best job convincing me of the velocity gets the number of points equal to the number of people who turn in this assignment added to their grade. The next best person gets a point lower followed by the person who does the best job of explaining the velocities getting one point.
How are you going to convince me? Well, you could use…
This is an individual activity. If you do the same thing as someone else (I will tell) you (and your buddy) will be disqualified. Also, don’t do anything illegal to do this.
This is due a week from today (Monday, April 19th). You can either turn something in or email me something. let me know if you have questions.
I hope you all are having a wonderful Spring Break…I know I am! My problem with Spring Break is that it makes it feel like summer for a week which makes it all the worse on Monday when you have to return to school.
Congrats to Sam for winning the Bracket Challenge…the final results are posted below: 
I have AP information for you. I’m just going to cut and paste the email I got from Mrs. Carroccio as it has information for all the AP tests. The email is as follows:
AP examinations are less than a month away. As you prepare students for the test, please remind them of the following items:
Test Date Location Arrival Time
| AP Calculus | May 5, 2010 | Dallas Bay Baptist Church | 7:40-7:45 |
| AP English Literature | May 6, 2010 | Dallas Bay Baptist Church | 7:40-7:45 |
| AP US History | May 7, 2010 | Clear Creek Church of Christ | 7:40-7:45 |
| AP European History | May 7, 2010 | Daisy Church of God | 11:30-11:40 |
| AP Physics – Mechanics C | May 10, 2010 | Dallas Bay Baptist Church | 11:40-11:45 |
| AP English Composition | May 12, 2010 | Dallas Bay Baptist Church | 7:40-7:45 |
Cell Phone Use – PLEASE STRESS THIS INFO TO THE STUDENTS
This is an abbreviated excerpt from the College Board Security Policy:
Since the May 2004 exam administration, cell phones and other electronic devices have been prohibited from the exam room and may not be used during the break. Students also receive a final warning to turn over cell phones and other electronic devices as part of the exam instructions. Despite these warnings, over 100 students in 2009 had their exam scores cancelled because they had used a cell phone during the exam or on the break (one of those 100 was a SDHS student).
The College Board strongly encourages you to publicize the prohibition of cell phones and other electronic devices prior to exam day so that proctors do not spend valuable time collecting these items from students. If a student uses any electronic device it will be confiscated and the student will be dismissed from the exam. We must hold the phone until the Office of Testing Integrity has been notified. We will then follow their instructions regarding confiscation of the phone.
So….please tell your students to leave their cell phones locked in their cars. For students who do not yet drive, please leave the cell phone at home.
Today we talked about the always exciting “Moment of Inertia”. The moment of inertia refers to how the mass in an object is distributed. If all the mass is on the outside, it is tougher to turn. Be sure to look through section 8.5 to see how the moment of inertia links torque to angular acceleration (and all the other Physics we’ve had so far).
The homework is as follows: Read and work out example 8.11 in the text. They work the problem out for you so follow along. When you master that, do problems 31, 32, and 33 in the back of the chapter. If you will not be here tomorrow, do number 34 as well (we will do that together in class…it’s a beast).
Be sure to check back here during Spring Break as I’m going to have you look at a few topics that I don’t want to spend a ton of time doing.
Go to http://www.learnapphysics.com/apphysicsc/rotational_motion.php and check out all the videos that are available to help you with Angular Dynamics. I particularly like the videos that are followed by “(Monterey)”, they walk you through problems and ask you questions as you watch.
All of these videos are fairly short and easy to understand…check them out!
In this chapter we will be applying all of the linear Physics knowledge we’ve gained over the past 9 weeks or so and apply it to turning things. Last chapter gave us a good introduction to this, but we’re hitting it hard and heavy this chapter. Among the things we will be discussing are:
As you can see, there’s a bunch of stuff. Thankfully, most of the new things we’ll cover plug into things we’ve already talked about so it shouldn’t be as bad as covering them the first time.
We will obviously not be able to finish this chapter before Spring Break. This means that you will have to do work over Spring Break to help you remember what we have done. We can’t start over the Monday after Spring Break. We are moving on, if you don’t do your work and don’t keep up over Spring Break – you will be behind.
Today, we looked at the 1st couple sections of Chapter 8 and talked about the idea of torque. To keep up, your homework tonight is to look through sections 8.1-8.4. Make sure to try the example problems, especially Example 8.2, 8.3, 8.4 and 8.6. If you don’t understand any of the examples, please come to class with questions.
A website that can be used for some help can be found at http://www.physics.uoguelph.ca/tutorials/torque/Q.torque.intro.html
There are 10 types of people.
Those who understand binary, and those that don’t.
Today we looked at some problems dealing with angular kinematics and centripetal acceleration/forces. These problems were a little easier than the test, just as the problems the day before were a little tougher. The test will feature problems that are in the middle (I’m probably going to err on the side of being a little more like the hard worksheet than the easy. The worksheet can be downloaded here if you were absent.
Answers…
I’m free 1st period if you have any questions.
Today in class we looked at a few problems dealing with centripetal force. I know this is tough for most of you. We are getting to the end of the year and your attention is starting to waver. This is a part of Physics that is brand new to all of you and not very intuitive. In order to succeed in the last few weeks of class, you’ve got to really pay attention and ask questions. This stuff won’t make much sense until it “clicks”. For some people, it “clicks” quickly and for some people it takes a little while. The time it takes doesn’t relate to how smart you are or anything, it just makes sense to some people.
The moral of the story is…don’t give up. I know it can be frustrating not understanding what’s happening. Trust me, I felt like that many times in college when I was surrounded by Physics majors in ridiculous classes. You will get through it…don’t give up!
Anyway…sermon over…here are the answers…
If you lost the worksheet, download it here.
Please come to class tomorrow with questions. If you don’t know how to do this stuff, please ask until you figure it out. I’ll be here after school tomorrow if you want to stay and get some help
