Enigma machines

Ashton and I have made up some study devices named Enigma machines. Right now, we have two ready for you:

1. Strength of Gravitational Force
2. Trouble in Outer Space

They let you work step-by-step through some of the calculations in chapters 5 and 6. Look for them in Lecture Files.

Suggest a question for midterm 2

You can suggest a question for the second midterm, same method as before -- in Discussions. If it is good enough and we use it on the exam, then you get 1 bonus point.... and anyone who has studied it will likely grab that question on the test!

 

Topic areas for the exam

1. circular motion (chapter 4)
2. chapter 5
3. chapter 6 or
4. the topics of chapter 7 that we cover on 2/19

Homework 9 is ready

Go ahead to HW 9 in Webcourses. It is due on Tuesday morning.

Office hours now in progress, Starbuck's, UCF bookstore, until 4:15 PM.

Subtotals

I just set up subtotals for your HW scores and both kinds of CPS score. These rows are at the top of the HW/CPS subsection of your My Grades page. Every week, I will upload new CPS scores from lecture, and Webcourses will generate HW scores. I will update HW and CPS subtotals each week.

With the subtotals, you can keep an eye on your grade's "dynamical" state and see how it evolves over time.

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SIDE NOTE:
Some of you might see a number in parentheses. In our grade book, if at least one row referenced in the formula for the calculated subtotal has a value, a running total appears.

For example: with a formula that calculates the sum of the HW88 and HW202 scores, if there is a value in the HW88 row, e.g., 12, but not the HW202 row, the HW88 value appears as a running total, (12).

Running totals are italicized and appear in parenthesis.

After there is a value in the HW202 row, e.g., 3, the formula is completed and appears in plain text like other grade book entries, a plain old 15.

HW 8 is ready, but make sure to read...

Homework assignment #8 is now ready to go, due Thursday morning. Before hitting the HW, make sure to read the Halley and Newton biographical blurbs in the Lecture Files. The last exercise is a brain-burner, meltdown time. Excellent.

HW 7 ready to go: study in chapter 5 required.

Homework assignment #7 is now ready for you inside Webcourses. It is due next Tuesday, as usual.

Unlike the usual thing, however, you have to read some pages in chapter 5, on tides, before tackling the HW. I.e., it is a study homework.

Caught nappin'

Take a look at the Lecture Files in Webcourses. There is a file for exercise 10, p. 73, which we were working on at the end of lecture. I made an error in the orbital speed computation, which was spotted by Morris and Katherine. The new lecture file for exercise 10 has the correct computation, along with some comments on the law of universal gravitation in chapter 5.

Gracias, Katherine and Morris!! I was nappin'!!

Thursday's lecture = GO

We will have regular lecture on Thursday morning, back to the normal schedule.

Thursday's lecture will be on gravitation, so do some reading and skimming in chapter 5, if you have 30 min. Especially look at the diagrams and illustrations. We will review and elaborate the blurb on p. 81, "Working it out|Gravity" plus some of the exercises on circular motion and orbits from chapter 4, p. 73:

1. exercise 8, generic circular motion;
2. exercise 9, Earth-Sun orbital system;
3. exercise 10, Earth-Moon orbital system.

You can eyeball those tonight and maybe bug Ashton and Meg with questions in Discussions. :)

See you Thursday morning, GO FOR LAUNCH!

Accurate diagram of Earth-Moon system

No HW for Thursday

Sorry. I have been so busy getting healthy that I have not gotten to an assignment for you for tomorrow (Thursday) as I had expected to do. I know that it is SO disappointing to not have any HW again, but you will just have to try to keep your composure. :)

See you in lecture, on Thursday. We will have exam printouts to hand back.