# AT Cycle 9

## 10/25 - 10/30

W 10/25

Th 10/26

F 10/27

M 10/30

### 🔴 2: Th 10/26a, 🟡 4: W 10/25, 🔵7: W 10/25 - rotational kinematics

Daily Check-in: translational vs. rotational variables

Today, fill out the handout first which will relate Translational & Rotational Kinematics Variables. Then, we'll do problems from Chapter 10 which will allow you to practice applying the rotational kinematics formulas.

Support: 3, 4, 10

Required: 6, 7, 14, 16, 22, 26, 28, 32

Enrichment: 8, 17, 31

Use the notes you took on the video you saw last night. If you finish early, start watching the many videos for tonight's homework.

Homework: The above problems are due in ✏️ Google Classroom by Friday, October 27th at 10pm. Watch the following videos on center of mass. Although there are quite a few videos, each one is not very long.

If you can get ahead on homework videos from the next post, that'd be great. Watch the first two videos below. We'll need this information by Tuesday, and there are 4 longer videos to watch Monday night. If you have Halloween plans, you may want to watch all 4 of the videos from the next post over the weekend. They are very important!!!

### 🟥❗ 2: Th 10/26b, 🟨❗ 4: Th 10/26, 🟦❗ 7: Th 10/26a - density lab

Today, we'll review what you know about density and introduce the concepts of linear and surface densities. We'll perform a lab together that requires you to measure, estimate, and find other information. Write up your lab, and hand it in next class.

If you finish early, then start watching the videos below on center of mass.

Homework: Watch the following videos on finding the center of mass of an object. The first video shows you the theory on finding the center of mass. The second video shows you how to find the center of mass of an object using the summation. The third and fourth videos show you how to use the integral to find the center of mass. Sorry for the long homework.

By ❤️ 2: F 10/27, 💛 4: M 10/30a, 💙7: Th 10/26b, watch:

... and by 📕 2: M 10/30, 📒 4: M 10/30b, 📘7: F 10/27, watch:

Center of mass example with calculus:

### ❤️ 2: F 10/27, 💛 4: M10/30a, 💙7: Th 10/26b - center of mass problems (1)

Daily Check-in: center of mass summation (a similar example if you missed class)

Today, we'll collaboratively solve center of mass problems from Chapter 9:

Support: 2, 4

Required: Sample prob 9.02, 5, 7, 8, 15, 16, 17, 114, G65

Enrichment: 14, G66, G67

These problems will require you to use the calculus and what you learned about different kinds of densities.

Homework: Quiz on center of mass, rotational kinematics, and tipping - Wednesday, November 1st. Work on at least half of the required problems from the set above. It is very important that you do these required problems. Also, make sure that you're comfortable with Example 9-14 on page 223 of the Giancoli textbook. Try recreate the solution the problem from the 3rd and 4th video from last night independently. That means to write out your own solution without watching the video. The problem is to find the center of mass of a non-uniform rod length L where λ = kx3. Then, answer the following questions in a ✏️ Google Classroom assignment by Monday, October 30th at 10pm.

How do you know that you need an integral to solve this problem?

What general formula do you need to use?

Why do you need to change the formula to dx?

How do you change the formula to dx?

How do you know which variable determines the limits?

How do you know where x = 0? (kind of a trick question)

How do I know the units of my solution are correct?

If you get stuck, rewatch the videos:

### 📕 2: M 10/30, 📒 4: M 10/30b, 📘7: F 10/27 - center of mass problems (2)

Daily Check-in: center of mass integral

Today, we'll collaboratively solve center of mass problems from Chapter 9:

Support: 2, 4

Required: Sample prob 9.02, 5, 7, 8, 15, 16, 17, 114, G65

Enrichment: 14, G66, G67

These problems will require you to use the calculus and what you learned about different kinds of densities.

Homework: Quiz on center of mass, rotational kinematics, and tipping - Wednesday, November 1st. Finish all required problems you did not get to in class. It is very important that you do these required problems. Also, make sure that you're comfortable with Example 9-14 on page 223 of the Giancoli textbook. Try recreate the solution the problem from the 3rd and 4th video from last night independently. That means to write out your own solution without watching the video. The problem is to find the center of mass of a non-uniform rod length L where λ = kx3. Then, answer the following questions in a ✏️ Google Classroom assignment by Monday at 10pm.

How do you know that you need an integral to solve this problem?

What general formula do you need to use?

Why do you need to change the formula to dx?

How do you change the formula to dx?

How do you know which variable determines the limits?

How do you know where x = 0? (kind of a trick question)

How do I know the units of my solution are correct?

If you get stuck, rewatch the videos:

And if you need a review of the center of mass integral that we did in class, watch my video: