## 20160817

### Online reading assignment: course policies, significant figures, unit conversion, dimensional analysis

Physics 205A, fall semester 2016
Cuesta College, San Luis Obispo, CA

Students have a bi-weekly online reading assignment (hosted by SurveyMonkey.com), where they answer questions based on reading their textbook, material covered in previous lectures, opinion questions, and/or asking (anonymous) questions or making (anonymous) comments. Full credit is given for completing the online reading assignment before next week's lecture, regardless if whether their answers are correct/incorrect. Selected results/questions/comments are addressed by the instructor at the start of the following lecture.

The following questions were asked on reading textbook chapters and previewing presentations on significant figures, course policies, unit conversions and dimensional analysis.

Selected/edited responses are given below.

Describe what you understand from the assigned textbook reading or presentation preview. Your description (2-3 sentences) should specifically demonstrate your level of understanding.
"To be completely honest I never really understood significant figures. They were always sort of a blur that I never looked forward to deal with. However, with this presentation preview, I know understand completely with the flow chart! It makes total sense and in chemistry we would write some as ambiguous but the 'rule of two' is really clarifying for some of the concerns I had earlier."

"For multiplication/division you need to know the value with the fewest significant figures while on addition/subtraction you need to know the decimal places."

"From the presentation previews, I could barely recall the information on significant figures in terms of addition/subtraction and multiplication/division. After reviewing the presentation, it makes more sense to me and I was able to come up with an easy way to remember the rules of significant figures. It seems like an easy rule to remember as long as you practice the rules and study them everyday."

"The text was more of a review of SI units which can be expressed with prefixes depending on multiples of ten. How those units can be converted and behave like algebraic quantities by canceling. Dimensional analysis relates that unit to whats physically happening."

Describe what you found confusing from the assigned textbook reading or presentation preview. Your description (2-3 sentences) should specifically identify the concept(s) that you do not understand.
"There wasn't anything in the presentation previews that I found immediately confusing, however accessing the blog from the home page was a little challenging."

"Just got my book today so haven't really read it thoroughly just yet."

"The dimensional analysis section seemed to just throw a lot of numbers at me without really giving me a specific meaning. I guess I just need a little clarification in class."

"I found that the dimensional analysis portion was very confusing. One thing that is very confusing is not the conversion of units, just the memorization of the different SI units needed in the class."

"I didn't really find the content in the presentations confusing, for the most part it was pretty basic and a little review. But I did find it difficult trying to find the presentations. For some reason it took me a really long time finding the weekly assignment list" "

Indicate how your course grade would be affected for each of the following cases.
(Only correct responses shown.)
Not completing online homework reports: one-half of a letter grade. [54%]
Missing three labs: failing the course. [71%]
Missing three quizzes: not at all, or not much. [51%]
Absent on a midterm day: depends on if/whether there is an acceptable excuse. [54%]

Indicate how your course grade would be affected for the case of only coming to half of the lectures.
 Not at all, or not much. **** [4] One-half of a letter grade. **** [4] A whole letter grade. **** [4] Two whole letter grades **** [4] (Depends on if/whether there is an acceptable excuse.) **** [4] Failing the course. ** [2] (Unsure/guessing/lost/help!) ************* [13]

Match the SI (Système International d'Unités) prefixes with their corresponding powers of ten.
(Only correct responses shown.)
centi- (c): 10–2. [94%]
giga- (G): 109. [89%]
kilo- (k): 103. [97%]
mega- (M): 106. [89%]
micro- (µ): 10–6. [89%]
milli- (m): 10–3. [89%]
nano- (n): 10–9. [97%]

Mark the level of your exposure to units and dimensional analysis.
 None at all. ** [2] Slight **** [4] Some. ********* [9] A fair amount. *************** [15] A lot. ***** [5]

Ask the instructor an anonymous question, or make a comment. Selected questions/comments may be discussed in class.
"I am a little confused as to where the assigned readings are posted. I probably just missed it somewhere." (On the "Tuesday" tab for this week, "Read Physics, 10/e: Appendices A, B; Chs. 1.2, 1.3; online presentations (*.blog), (*.blog), course policies (*.html), where the "blog" and "html" links are to the appropriate online content. Admittedly one of those links was originally garbled but was corrected later.)

"I couldn't find your class required book using the ISBN number. I was wondering if the Physics 10th edition by Cutnell is enough? I saw it said 'custom' and so I didn't know if it was the same. I kind of wanted to get it used or rent it because of cash flow." (The Cuesta College Bookstore offers a "custom" (paperback) version of just Chs. 1-17 of the original complete textbook, but as long as you can get those same chapters of the current (10th edition) textbook for cheaper, that will be fine.)

"I like it when things are gone over in lecture, then we are given examples to see how it is done. Sometimes the explanation isn't enough for me, and I would like it to be done in-depth once or twice. I know not everyone likes this way of teaching, but if this isn't the general consensus, then no worries. I can refer to homework and notes and your office hours if I need clarification." (Well, this isn't a totally independing-learning free-form class, ideally with the feedback the class gives me on their comprehension of previous topics and/or new topics, this will guide me on targeting which and how much to "go over" certain topics in class, as needed.)

"I was wondering if all the reading assignments would be on the website? Also, where are grades posted? On the myCuesta website or on the website you have us use?" (Grades will be posted on our course website, as well as the reading assignments and homework reports (which actually link through to SurveyMonkey.com).)

"I am really hoping this course will emphasize understanding the "why" of things, and not be all about memorization." (I hope so, too. The essay questions on the midterms and the final exam will emphasize this type of understanding (along with multiple-choice and solved-problems).)

"Why do you believe that the second place of '80,000' is significant when so many other teachers (for example all of the chemistry teachers I've taken) don't believe that it is?" (That is certainly up for debate, but we'll use the somewhat arbitrary "rule of two" convention that is followed by many physics textbooks. Also, Sith Lords. #alwaystwothereare)

"I thought you showed us a link to a PDF of the first chapter of our book?" (Uh, no. Not this class.)