Circular Motion Review

For all you folks hoping to review circular motion before the quiz tomorrow, here are a few videos that I found helpful in breaking down uniform circular motion.

Happy sciencing! 

Momentum Lab Tasks

There are three videos that you will need to analyze for the lab tasks today.

Ball-Rebound Video

1. What is the change in momentum of the ball during the collision?
2. What impulse is imparted on the ball during the collision?
3. What is the magnitude of the average force of the wall on the ball during the collision?
4. Do you think the force exerted on the ball is constant during the collision, or that the force varies during the collision?
5. Can you make an estimate of the peak force on the ball during the collision? What assumptions do you make in the process of estimating?

M&M candy colliding with a cart Video

1. What is the speed of the M&M before the collision with the cart?
2. How do you think the actual speed of the M&M compares with your predicted value? 

Boy on a paddleboard Video

1. What is the ratio of the mass of the boy to the mass of the paddleboard?
2. If the mass of the boy is 32 kg, what is the mass of the paddleboard?

CAPM 2 Answers

The answers to CAPM 2 have been uploaded.

Go to Files > AP Physics > CAPM > CAPM PSet 2 Answers

If you have a clarifying question about any of the problems, comment below.

(AP Physics) Three Things

1) If anyone has any pictures or videos from tug of war today, send them my way!

2) Congrats 1B! Y'all scored mastered a ton of standards today. I still have yet to grade the question for STT.2, but everything else is updated on the Master Excel File and soon to be updated on PowerSchool.

3) I recently uploaded a step by step guide to drawing a free body diagram and solving for missing forces. Check if out if you're having trouble with this. Our balanced forces SA will be coming soon. I'll give you a specific date by Sunday.  To find the file, go to Files > AP Physics > 3 - BFPM > FBD Step by Step

(AP Physics) Problem 7: Pulling a block

Having problems with the 2-dimensional FBD homework?

Check out this video of my explanation to problem 7 for guidance. 

Physics Sequence

Here's the link to the physics sequence through November.

Solutions to 5+6

Here are my solutions to problems 5 and 6 from the HW due 9/24(2A) and 9/25(1B).

Keep in mind that there might be some rounding differences in Problem 5. Considering the accuracy of each force measurement, we would argue that the sum of forces in the X and the sum of the forces in the Y is 0. So the object would move at constant velocity.

Email Address Form

Click on this link and fill out your email information.

System Schema and FBD Practice Problems (1-5)

Try the practice problems (1-5) we started in class (9/21 and 9/22) and then check your answers to these solutions.

Problem 2

Problem 2

Problem 3

Problem 4

Problem 5 (Can you spot the two mistakes on this board?)

Proportional Reasoning Examples

For the college-prep and honors classes:

Here is a video of the solutions to #3 and #10 from the proportional reasoning worksheets. Comment below this post if you have questions about a particular step. 

Bike Cop and the thief (#3) + Homework

Here's the video of my solution to question 3 involving the angle of attack of the bike cop to collide with the thief.

For homework (2A and 1B): Watch this 10-minute introductory video on forces and take notes.

Solutions to the multiple representations practice

Here are your solutions that you drew up in class (1B). There will almost certainly be one question on the AP Exam asking you to convert motion from one representation to another.

1

2

3

4

5

7

Where are 6 and 8, team?

Practice 2: Comparing Position-Time Graphs

Here are the solutions you worked out in class (2A).

3A + B

4A + B

5A

5B

Understanding Retakes

I received an email from a student yesterday inquiring about re-assessments. I thought to post my response here. I want you all to understand how you're being graded. 

If I did well on some of the standards in a quiz, but not all, would I be tested again only on the standards I did not do well on?

Once you score a 3 on a particular standard, you are set with that standard for the mastery component of your grade (80%). When the standard comes back up on future standard assessments I will still score it, but you won’t be pulled down from a 3 to a 2. Only the standards that you haven’t yet mastered can impact your grade. So you should devote the majority of the SA time to these standards. 

 Also, what constitutes proof of practice? 

Proof of practice will be the assigned homework or in the case of our first unit on scientific tools, the summer work. The summer work includes standards 3, 4, 5, 6. If you would like to practice standard 1 I have a problem on my website you can try (click files, AP Physics, 1- Scientific Thinking). You will show me the practice you completed to prepare for the next standard assessment. After a conversation with me about this practice, I will give you another SA. 

A related question: When is a convenient time for me to retake the quiz that we took two classes ago?

I plan on giving you all an SA next class on STT.1, 2, and 3 and then another one on Thursday covering 4, 5, and 6. If you would like to complete another assessment outside of these times, you can do so during your lunch period. Just let me know in advance so I can have everything prepared.

You can comment below if you have any other questions about my flavor of SBG and I will respond. 

Help with curve fitting

Watch this video if you are struggling with curve fitting. I cover data set 2 on the graphing practice worksheet. This skill is standard 4 in the scientific thinking and tools unit for college and honors classes (standard 2 for AP). Happy plotting! 

Summer Work

Use this answer key to the summer work to determine your weaknesses. Your standards assessment is on Tuesday (A) and Wednesday (B). If you are not getting some of these answers on the summer work, talk to each other or talk to me. I am available on Thursday and Friday after school. You might find the standards sheet a helpful guide. For instance, can you confidently say that you are able to "manipulate an expression to solve for any given variable (STT.3)? If not, practice!

Sources on asking good questions

Always the beautiful answer, who asks a more beautiful question.

- E.E. Cummings

Coming up with good questions is difficult. If you are stuck in the mire of this task visit a few of the following sources to help free yourself to ask better questions. 

How to ask good questions

General techniques for asking good questions:

- Isolate the components

- Consider all the attributes and combination of attributes

- Explore white space (missing aspects)

- Consider extremal cases

- How does X depend on Y?

- How to measure?

Contrasting low order and high order questions

Why we ask questions

The importance of asking thoughtful questions

You will only refine this craft with practice. So ask more questions in conversation. Ask more questions in the classroom. Ask more questions of yourself. Why are you doing what you're doing?