20160130

Astronomy current events question: visible light fluctuations from black hole V404 Cygni

Astronomy 210L, spring semester 2016
Cuesta College, San Luis Obispo, CA

Students are assigned to read online articles on current astronomy events, and take a short current events quiz during the first 10 minutes of lab. (This motivates students to show up promptly to lab, as the time cut-off for the quiz is strictly enforced!)
Jessica Hales, "'Seeing' Black Holes with Home-Use Telescopes" (January 7, 2016)
kyoto-u.ac.jp/en/research/research_results/2015/160107_1.html
Visible light fluctuations triggered by __________ can be observed from black hole V404 Cygni.
(A) neutrino bombardment.
(B) companion stars.
(C) infalling material.
(D) antimatter.
(E) gravity waves.

Correct answer: (C)

Student responses
Sections 30678, 30679, 30680
(A) : 3 students
(B) : 14 students
(C) : 15 students
(D) : 4 students
(E) : 11 students

Astronomy current events question: damped Lyman alpha systems

Astronomy 210L, spring semester 2016
Cuesta College, San Luis Obispo, CA

Students are assigned to read online articles on current astronomy events, and take a short current events quiz during the first 10 minutes of lab. (This motivates students to show up promptly to lab, as the time cut-off for the quiz is strictly enforced!)
Jessica Hales, "New Method Solves 40 Year-Old Mystery on the Size of Shadowy Galaxies" (January 6, 2016)
swinburne.edu.au/news/latest-news/2016/01/new-method-solves-40-year-old-mystery-on-the-size-of-shadowy-galaxies.php
Light from background galaxies can be used to map damped Lyman alpha systems (DLAs), which are ancient:
(A) cold gas clouds.
(B) metal-rich stars.
(C) alien structures.
(D) red dwarfs.
(E) big bang ripples.

Correct answer: (A)

Student responses
Sections 30678, 30679, 30680
(A) : 34 students
(B) : 2 students
(C) : 0 students
(D) : 4 students
(E) : 7 students

Astronomy current events question: runaway star bow shocks

Astronomy 210L, spring semester 2016
Cuesta College, San Luis Obispo, CA

Students are assigned to read online articles on current astronomy events, and take a short current events quiz during the first 10 minutes of lab. (This motivates students to show up promptly to lab, as the time cut-off for the quiz is strictly enforced!)
Whitney Clavin, "Runaway Stars Leave Infrared Waves in Space" (January 5, 2016)
jpl.nasa.gov/news/news.php?feature=4812
Massive, runaway stars can be identified from NASA's Spitzer Space Telescope and Wide-field Infrared Survey Explorer images of:
(A) type Ia supernovae.
(B) Doppler shifts.
(C) dark matter filaments.
(D) x-ray fluctuations.
(E) bow shocks.

Correct answer: (E)

Student responses
Sections 30678, 30679, 30680
(A) : 5 students
(B) : 6 students
(C) : 2 students
(D) : 6 students
(E) : 28 students

20160129

Online reading assignment: total internal reflection, polarization

Physics 205B, spring semester 2016
Cuesta College, San Luis Obispo, CA

Students have a 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 total internal reflection and polarization.

The reflection of the fish is upside-down.  Does that make sense?

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.
"There are three cases in which light will start in a higher refractive index material: the incident angle is less than the critical angle; the incident angle is equal to the critical angle; or the incident angle is greater than the critical angle."

"For all incident angles less than the critical angle, both refraction and reflection can occur."

"A horizontal antenna works with horizontally polarized light. A vertical antenna works with vertically polarized light."

"I understood pretty much all of the basic concepts pretty well! And i really liked the applications that was shown in the blog."

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.
"I couldn't understand how the applications work. For example, antenna and optical fibers."

"I think I will need more help on total internal reflection. I somewhat understand the equations that are shown in the pictures in the presentation but the explanations underneath confuse me. How do we know if the transmitted angle is subject to Snell's law?"

"I do not get anything on polarizers. Maybe will help if covered in class."

"The math of it all, mostly. I just need more practice, I understand the concepts pretty well."

If the incident angle of a light ray is less than the critical angle, the light ray will be:
reflected.  * [1]
transmitted.  *************** [15]
(Both of the above choices.)  ******************** [20]
(Neither of the above choices.)  [0]
(Unsure/guessing/lost/help!)  ** [2]

If the incident angle of a light ray is greater than the critical angle, the light ray will be:
reflected.  ********************************** [34]
transmitted.  ** [2]
(Both of the above choices.)  ** [2]
(Neither of the above choices.)  [0]
(Unsure/guessing/lost/help!)  [0]

Total internal reflection is possible when a light ray in a __________ medium hits a boundary with a __________ medium.
faster; slower.  ******** [8]
slower; faster.  ************************* [25]
(Both of the above choices.)  ** [2]
(Unsure/guessing/lost/help!)  *** [3]

A vertical antenna will emit __________ polarized light.
horizontally.  ***** [5]
vertically.  ********************************* [33]
(Both of the above choices.)  [0]
(Neither of the above choices.)  [0]
(Unsure/guessing/lost/help!)  [0]

Horizontally polarized light can be received by a _________ antenna.
horizontal.  ********************************** [34]
vertical.  **** [4]
(Both of the above choices.)  [0]
(Neither of the above choices.)  [0]
(Unsure/guessing/lost/help!)  [0]

Ask the instructor an anonymous question, or make a comment. Selected questions/comments may be discussed in class.
"I'm liking the 'preview previous blog responses' area on the website! It helps me go back and make sure I do or don't understand the material!"

"Is there any meaningful difference between the custom textbook and the original textbook?" (In terms of content, no, other than the weird double-numbering of the pages.)

"I got called into work the nights I intended to do this assignment. I'm actually at work right now."

"I'm so tired of school. All I want to do is sleep and eat without getting fat, and get really smart without trying." (#nopainnogain)

"I was rolling huge tires today in-between sprints. It was awesome. It hurts so good." (#flexfriday)

"What's your exercise of choice, other than swing dancing? Mine's running." (Mrs. P-dog and I go hiking, in order to train for backpacking or peakbagging in the Eastern Sierras.)

20160127

Online reading assignment: flipped classroom, motions and cycles (SLO campus)

Astronomy 210, spring semester 2016
Cuesta College, San Luis Obispo, CA

Students have a 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 Earth's rotation/precession/revolution/tilt, the moon's motions and cycles, and watching two video presentations on the flipped class: "What Is the Flipped Class?" and "How the Flipped Classroom Works."

Selected/edited responses are given below.

Describe something you found interesting from the assigned textbook reading or presentation preview, and explain why this was personally interesting for you.
"That Australians can't see the Big Dipper--it made me wonder if there are any constellations we here in the United States can't see that Australians can."

"The moon's phases, because I always thought the moon was really cool and felt I should know them, but never really learned them! Also, I always get excited when I see a full moon so it'll be nice to be able to keep track now."

"That Earth's precession takes 26,000 years, and because of that precession we don't have a permanent north star. It's fascinating to me that it takes that many years to complete one cycle of the alignment of Earth's axis. That's just so long!"

"I was stoked to find out what zodiac signs actually were. I've been asked often what my sign is, and I know I'm a Virgo, but I've never understood why. Now I understand that it actually is defined by a set calendar, and I'm glad to have that cleared up :)"

"I actually loved learning about the flipped classroom, I think it's a really interesting idea."

"I really liked the videos/pictures. They helped me visualize instead of having to just read about it."

"I really liked the idea of a flipped classroom. Last semester I took statistics, and every day I would go into the math lab in the student center to do my homework and get help if needed. Doing that made the class way easier. In that scenario I did pretty much use the professor's lecture as a preview or general idea about the concept and then I would go into the math lab to fully understand it and it worked very well for me."

Describe something you found confusing from the assigned textbook reading or presentation preview, and explain why this was personally confusing for you.
"The different Earth motions--how can it take 26,000 years for it to complete one cycle of precession, but only 24 hours for it to complete one rotation."

"How to find when the sun would line up with certain zodiac constellations."

"How to properly use the starwheel, and I'm also confused about the moon phases. It doesn't really show what comes first and what comes last."

"The differences between Earth's tilt, rotation, revolution, axis and precession. I know that they each are Earth moving in a different way, but it's really hard for me to differentiate which one is which and picture Earth moving in my head."

"Visually distinguishing the moon phases. I understand the differences between waxing versus waning moon phases, and crescent versus gibbous, but when I look at a photo I still get confused. Thankfully I drew a chart in my notes to help myself!"
"It was not confusing at all."

What date would Virgo be just above the east horizon, as seen by an observer at 11 PM in San Luis Obispo, CA? (Ignore daylight saving time.)
February 20.  *********************** [23]
April 25.  [0]
July 4.  * [1]
August 20.  ****** [6]
(Unsure/guessing/lost/help!)  ******** [8]

Match these cycles with their approximate duration.
(Only correct responses shown.)
Earth's rotation: 24 hours [97%]
Earth's revolution: one year [90%]
Earth's precession: 26,000 years [97%]
The moon's revolution: one month [97%]

Place these moon phases in chronological order in their cycle (starting with new moon).
(Only correct responses shown, in unscrambled order.)
New moon: first [89%]
Waxing crescent: second [82%]
First quarter: third [87%]
Waxing gibbous: fourth [82%]
Full moon: fifth [82%]
Waning gibbous: sixth [82%]
Third quarter: seventh [79%]
Waning crescent: eighth [71%]

Explain what is different about homework in a flipped class.
"The homework is more of a presentation of what you're going to be working on in the next class."

"Homework in a flipped class is all done online and can be taken at it's own pace with lots of other resources to help them learn."

"The flipped approach entails moving homework into the classroom, where the teacher can give personalized instruction to the students."

"Homework in a flipped class is way better because after class, the student has a better idea of what to do because they had so much face to face time with their teacher beforehand."

"Homework in a flipped class seems more difficult and time consuming because I would be teaching myself, where as a conventional class I'm taking notes and learning, then going home and continuing to learn by doing the homework and going over the information again."

Describe where/when most student learning occurs in a flipped class.
"In a flipped class equal time is shared learning in class and as well at home."

"Most of the learning a student does in a flipped class occurs before the class, in the readings."

"The most student learning should probably occur in class when the teacher gets to interact with the students and answer the questions that might have risen from their readings or studying. In a conventional class most learning is probably outside of class when the student has to review what they heard and wrote down in class as they do their homework to refresh their memory."

Ask the instructor an anonymous question, or make a comment. Selected questions/comments may be discussed in class.
"I am still a little confused on how to use the starwheel to be honest."

"Originally, my zodiac sign is Leo, but in some other astrology systems such as in Japan my zodiac sign is Virgo. My birthday is in early September." (Sounds like astrology in Japan is more legit.)

"It occurred to me that due to precession the locations of the zodiac constellations in the sky would shift slowly, just like Polaris. This made me confused as to whether there is a need for compensating for this in astrological zodiac signs."

"Can we go over how to remember the names of the moon phases?"

"I heard something about five planets lining up in the sky sometime soon and apparently it's going to look really cool. Can you show us?" (Here, let me show that to you.)

"I find the flipped class very interesting, I've never heard of it before."

"So I am actually not entirely sure if I was supposed to do this homework already or if this is next week's homework. I thought it was next week's homework because we haven't gone over this material yet in class, so I'm actually super confused. If this is true, I honestly think it's a little weird that we have homework on stuff that we haven't gone over yet in class." (It is a little weird, but that's the point of the flipped class. The 'homework on stuff we haven't gone over yet in class' is not meant to be comprehensive or complete, but just to start preparing you on the background and terminology for what we will eventually be discussing in class.)

"I like how you do so many activities such that the class isn't just lecture, since it's a long class as that would get boring so quickly. It really helped make the time pass and made the class really interesting."

"If some students have difficulty learning through the 'homework-flipped-in-a-classroom' method, how would you advise those students to do better? Since some students may dislike the many in class activities and flashcard questions, they might be frustrated at slow-paced group learning when they'd prefer the traditional way of learning." (Well, I understand how learning at a faster (or slower) pace than your group is always going to be an issue. However, I would consider being able to explain something to other students as a strong indicator of having mastered the material, and being able to ask questions and clarify things with other students (if you don't quite understand what's going on) as a first-resort resource for learning, before you really need to call over the instructor.)

"Do you enjoy astrophotography, or have you ever tried it? Is that your cat on your hat on your blog photo? What are you and Mrs. P-dog's favorite trails to hike in SLO county?" (Yes, yes, and actually we're just using hikes around SLO to train for backpacking in the Eastern Sierras.)

"With a nickname like 'P-dog' I think you need to rap." (Mrs. P-dog and I DJ swing music at the Madonna Inn. Does that count?)

20160126

Online reading assignment: flipped classroom, motions and cycles (NC campus)

Astronomy 210, spring semester 2016
Cuesta College, San Luis Obispo, CA

Students have a 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 Earth's rotation/precession/revolution/tilt, the moon's motions and cycles, and watching two video presentations on the flipped class: "What Is the Flipped Class?" and "How the Flipped Classroom Works."


Selected/edited responses are given below.

Describe something you found interesting from the assigned textbook reading or presentation preview, and explain why this was personally interesting for you.
"How the seasons change was really interesting because I never knew how that really happened, nor did I really question how it happened."

"I thought it was interesting to learn about the Zodiac signs and how they relate to astronomy because I never knew the meaning or origin of the symbols/animals."

"The lunar phases and changes were interesting to me. I see them every night, but never knew exactly what to call them until now."

"Precession, because of the fact that it happens at such a slow rate that we won't get to notice anything in our life spans but there is still very slow motion going on constantly."

"That seasons are caused by the revolution of earth around the sun as well as changes in solar energy received."

Describe something you found confusing from the assigned textbook reading or presentation preview, and explain why this was personally confusing for you.
"Something I found personally confusing was how to use the starwheel correctly."

"Precession--how it takes approximately 26,000 years to complete one cycle. It's confusing to me because the wording doesn't make sense to me."

"The cycle of the seasons to be slightly confusing to me just because there's a lot of different factors that go in to causing the seasons to change."

"I didn't quite understand the motion of the moon section. It stated that the moon moves rapidly, but I don't understand what is considered rapid and what wouldn't be. It didn't give a comparison so I could wrap my head on the speed."

"The textbook and presentations both talk about solstices and equinoxes, but neither really explain what they are. Like, what's the difference between the two? What makes those specific days so special that they're equinoxes and solstices?"

"Waxing, waning, and gibbous phases were confusing to me because I never heard of those terms before. after reading the meaning of them though it made sense."

"Something that was confusing for me was the zodiac and how it kind of goes hand in hand with the seasons."

What date would Virgo be just above the east horizon, as seen by an observer at 11 PM in San Luis Obispo, CA? (Ignore daylight saving time.)
February 20.  ************* [13]
April 25.  [0]
July 4.  [0]
August 20.  ** [2]
(Unsure/guessing/lost/help!)  *** [3]

Match these cycles with their approximate duration.
(Only correct responses shown.)
Earth's rotation: 24 hours [94%]
Earth's revolution: one year [72%]
Earth's precession: 26,000 years [89%]
The moon's revolution: one month [94%]

Place these moon phases in chronological order in their cycle (starting with new moon).
(Only correct responses shown, in unscrambled order.)
New moon: first [89%]
Waxing crescent: second [67%]
First quarter: third [78%]
Waxing gibbous: fourth [72%]
Full moon: fifth [83%]
Waning gibbous: sixth [78%]
Third quarter: seventh [72%]
Waning crescent: eighth [61%]

Explain what is different about homework in a flipped class.
"The difference about homework in a flipped class is that we get to preview the material before the lecture."

"The homework that is being worked on is what is upcoming in the next class, and will prepare you for what you are about to learn."

"Homework and handouts are given before the next lecture in a flipped class where as in a conventional class it is given after the lecture and taken home."

Describe where/when most student learning occurs in a flipped class.
"Most of the learning is done at home when the material is previewed before going to class, where the teacher/professor will then clarify any confusion."

"Student learning should take place in class after the students have already over-viewed the notes/handouts given before the lecture."

"I believe most student learning comes from working either with a teacher or with another student. I am usually very independent, but it helps when someone else can give you another perspective on what we are learning."

Pick one piece of student advice from the previous semester, and discuss why you agree (or disagree) with it.
"'Don't let yourself get behind! It will only make it worse.' I agree with this piece of advice because I've been in that situation before."

"'Do all the in-class activities, do the practice quizzes, midterms and final, then e-mail your answers to P-dog to get the correct answers and take the lab class for reinforcement.' I agree with this advice. Doing the in-class activities would not only keep your grade from going down, but also helps you understand the material. As for all the practice quizzes and such, it's a great way to study for quizzes and finals and getting the correct answers is a way to be sure you understand the content that you learn and get help if you don't understand something."

"'Be sure you always stay on top of the readings.' I strongly agree with that. This class seams to be the type of course that is self led in a way. We the students have to stay on top of the work since there is so much to be done outside of the classroom."

"'Rule 1 of Astronomy class: DON'T TALK ABOUT ASTRONOMY CLASS.' I like the reference...but talking about the class with people to get a better understanding. "

Ask the instructor an anonymous question, or make a comment. Selected questions/comments may be discussed in class.
"As I was previewing the presentations, I stopped many times because all this is new to me. It is personally confusing because I have never took the time to actually learn anything that has to do with 'astronomy.'"

"The reading in the book was confusing because there was more information in the book that I didn't really know what was good information or not. Thankfully the presentation previews helped with that."

"If due to procession Earth's north pole pointed to an empty part of the sky, what would we do without a northern star?" (Do what the ancient Egyptians might have done during their time, draw a line between two bright stars that would intersect the celestial north pole.)

"I'm really nervous about being able to keep up in this course. Although, I'm hopeful it will be a very engaging class and I will get a lot out of it. As long as I can keep up it should be a fun class."

"I am seeing positive outcomes as far as a flipped class."

"What do you think about Planet Nine?" (#iwanttobelieve.)

20160125

Online reading assignment: electromagnetic waves, reflection and refraction

Physics 205B, spring semester 2016
Cuesta College, San Luis Obispo, CA

Students have a 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 electromagnetic waves and redirecting light (reflection and refraction), along with advice from students from the previous semester, and videos on the flipped class mode of instruction used in this course.

To convince yourself that the frequency of the wave remains constant in either material, try this with a friend--when a crest appears from the left edge of the screen, say 'in.'  When a crest disappears at the right edge of the screen, have your friend say 'out.'

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.
"Electromagnetic waves are classified by their frequency. Index of refraction is used to gauge the speed of light in different media. Redirecting light can happen through reflection and refraction."

"I understand that the electromagnetic spectrum is mostly invisible to our eyes with the exception of visible light. Radio waves have the lowest frequency and Gamma rays have have the highest frequency. The two ways to redirect visible light are through refraction and reflection."

"Light is part of a larger spectrum of electromagnetic waves that include radio waves, x-rays etc. Light travels at different speeds and wavelengths (but same frequency) through different media. The index of refraction gives us info on how fast it travels in different mediums. The higher the index, the slower the medium. Light gets reflected at the same angle perpendicular to the surface. It is refracted at a different angle that can be calculated using Snell's law."

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.
"Mnemonic: Fast-to-slow, bend towards the normal.' Not sure what this means."

"Snell's law. I have no idea what I am doing with those thetas."

Consider light traveling either through air (nair = 1.0) or through water (nwater = 1.33). Light travels with the faster speed through:
air.  *********************************** [35]
water.  ** [2]
(There is a tie.)  [0]
(Unsure/guessing/lost/help!)  * [1]

A ray of light has an incident angle of 60° in air, and a transmitted angle of 36° in plastic. Determine what happens to each of the following parameters as the light passes from air into plastic.
(Only correct responses shown.)
speed v: decreases [79%]
frequency f: remains constant [66%]
wavelength λ: decreases [63%]

For the above example of light incident in air being transmitted into plastic, __________ has the greater index of refraction.
air.  ** [2]
plastic.  ******************************** [32]
(There is a tie.)  [0]
(Unsure/guessing/lost/help!)  **** [4]

A ray of light has an incident angle of 20° in plastic, and a transmitted angle of 29° in air. Determine what happens to each of the following parameters as the light passes from plastic into air.
(Only correct responses shown.)
speed v: increases [76%]
frequency f: remains constant [68%]
wavelength λ: increases [63%]

For the above example of light incident in plastic being transmitted into air, __________ has the greater index of refraction.
air.  ********************** [22]
plastic.  ************ [12]
(There is a tie.)  [0]
(Unsure/guessing/lost/help!)  **** [4]

State your preference for denoting the inverse sine operation.
Arcsin.  [0]
sin-1.  ************************************* [37]
(No preference.)  [0]
(Unsure/guessing/lost/help!)  * [1]

Explain what is different about homework in a flipped class, compared to a conventional class.
"We do our reading assignments, and read blogs at home before the next class begins and submit them online, then come to class and learn more about material based on how we did on the online assignments."

"Homework is different in a flipped class because it is more focused on attempting to understand the material on your own, then coming to class to ask questions and seek clarification."

"We work it out in class after studying the lectures."

Describe where/when most student learning should occur in a flipped class, compared to a conventional class.
"Most student learning should happen wherever you feel most comfortable I guess? You do the work at your convenience throughout the week, but class should be a place to hone your understanding."

"The learning should occur at home previewing lectures and material before class and then asking the instructor in class for clarification or help."

"Most student learning should occur at home and the information should be put into use in the classroom."

Pick one piece of student advice from the previous semester, and discuss why you agree (or disagree) with it.
"'Don't procrastinate, and keep up with the reading assignments and do the problems ahead of time.' I agree with this piece of advice because last semester I was trying to always catch up and it ended up getting me in the end."

"'Take notes on reading assignments and textbook reading, even if the material does not make any sense. Then show up to class, and add to the notes to finish any concepts that didn't make sense before. Take notes on all examples in class (this is one of the ways to study for quizzes and future midterms). Don't miss any classes, and practice, practice, practice + office hours!!' This piece of advice from the previous semester relates to me really well and it is something I already do."

"'Keep up with reading, studying material, quizzes and exams.' I found this piece of advice to be accurate because if you really want to understand all the material you have to keep up with reading the chapters and presentation blogs in order to understand how everything works. Also, the more practice problems you go over the better you will be at solving them and understanding them."

"'Solving more practice problems and not being afraid to ask questions!' This is the best advice I could give to other students because the practice problems provided by P-dog are the most similar to what you will find on quizzes/tests. And asking questions about topics you don't understand in my opinion is the only you will actually be able to understand confusing concepts, because re-reading things you don't understand will not make you figure out what you are trying to learn."

"'Do the damn homework: free points!' This was my own advice. While it is theoretically possible to just click submit on all the homework assignments without actually doing them, it's more likely that students will put at least some effort into the homework, thus making class time much more productive."

Ask the instructor an anonymous question, or make a comment. Selected questions/comments may be discussed in class.
"Can we review the index of refraction in a little more detail? I'm still a little confused and I'm not sure if what I comprehend is correct."

"I'm confused about how the different electromagnetic waves are actually produced. The book briefly covered it, but I didn't get it. For example, the book states that infrared waves are created by the movement of molecules. Does that mean that critters that can see in infrared are seeing moving molecules, or are they seeing heat produced from the moving molecules? If they are seeing heat, doesn't that mean that infrared is a type of 'visible' light, which is described as light produced by heat?" (All electromagnetic waves are produced by oscillating charges. The different types are produced by different-sized objects, have different-sized wavelengths, and are detected by comparable-sized objects. So the only difference between all of the electromagnetic wave types is scale.
      Radio waves are produced by electrons oscillating up and down large metal poles (antenna), have long wavelengths, and are detected by large metal poles as a "signal").
      Visible light is produced by rapidly oscillating atoms and electrons, have a shorter wavelength, and are detected by oscillating atoms and electrons (the valence electrons in certain chemical bonds in your rods and cones). When these chemical bonds are broken, the presence of these fragments in your rods and cones trigger your neurons to perceive "brightness").
      Infrared is between radio waves and visible light in scale--it is produced by vibrating molecules, and has a medium-sized wavelength, and is detected by vibrating molecules such as in your skin, which is what you perceive as "radiant heat.")


"Do materials that aren't clear still have a refractive index?" (Typically, no--if the material is opaque, then light can't travel through it, and then you can't define a light speed and a refractive index for that material. Some materials that look opaque will let some light through it if you cut a very thin sample of it, and in that case you could define a light speed and a refractive index for that material.)

"How does the light actually look like when it moves slower?" (Still pretty fast. Light always travels the same speed in the empty space between atoms, the trick to slowing light down is to make it spend more time being received and then re-transmitted at each atom (or crowd more atoms together).)

"I'm afraid of the disconnect that a flipped class might bring if someone falls behind slightly."

"This classroom 2401 feels weird to be in. I like the old classroom 2402 better. I feel disoriented and these little chair-desks are silly."

"Is there a new giant hidden planet beyond Pluto?" (#iwanttobelieve.)

20160114

Online reading assignment question: advice to future students

Astronomy 210, fall semester 2015
Cuesta College, San Luis Obispo, CA

Students have a 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. The following question was asked after the last lecture, but prior to the final exam.

Tell a student who is about to take this course next semester what he/she needs to know or to do in order to succeed in this course. (Graded for completion.)
"Do the online reading assignments! And do well early on so you can slack off later in the course."

"Don't let yourself get behind! It will only make it worse."

"Do the flashcard questions, they help a lot! Take time studying and maybe study on a schedule, there's a lot of information to know."

"Look around & look up at the sky, not just in the day but in the night, but everyday. Show up for every class, read the syllabus clearly understand the calendar & USE IT, WATCH & READ the videos, DO the online assignments and ask questions."

"DO all the in class activities, DO the practice quizzes, midterms & final & then EMAIL your answers to P-dog to get the correct answers and take the lab class for reinforcement."

"Do not procrastinate. Study for every test and do all the homework assignments. Read all the powerpoints. And lastly, take notes."

"Astronomy is not as hard as it sounds. If you try to keep up with the readings and ask questions in class you should do fine."

"STUDY STUDY STUDY do all of the flash card questions."

"Print out the in class activities, pay attention and study."

"Study the course material and do not slack off in the beginning of the class."

"Stay on top of the reading."

"Keep your eye on the prize. Don't procrastinate. Study!"

"Study and make all of the classes and you will do fine."

"Do the assignments, go to class, participate and ask questions!"

"Don't forget about the weekly online homework. Also do some small side reading about the stuff in the book since its only one source."

"DO THE READING QUESTIONS AND GO TO CLASS!!"

"Make sure to do the study guide packets and study groups are really helpful as well."

"Listen to P-dog."

"READ THE BOOK."

"Read. The. Book. Do. The. Homework. Go. To. Class. That's pretty much it."

"If you miss a homework assignment here or get a bad quiz score there, don't worry too much. As long as you don't give up and keep doing as much of the work as you can, you'll be fine."

"I think going through the slideshows before class each time is very helpful and going over flashcard questions helps as well. Pay attention and go to class because you will learn a lot and the professor makes the class really fun and intriguing!"

"Keep up with all the assignments, and always review the quizzes!"

"If you attend Lectures and read the material, you will do well."

"You need to always do your homework and pay enough attention in class to understand the material. it should not be that hard."

"Come to class and don't forget the reading assignments."

"Rule 1 of Astronomy class: DON'T TALK ABOUT ASTRONOMY CLASS..."

"As P-dog will stress--Go to class! Attending class, staying on top of the blogs and homework as well as the book readings is key to success in this class."

"In order to succeed in this course you definitely need to come to class every week and read the book!"

"You need to know how to take good notes, and pay attention. Create an outline from his presentations because it is not done for you and will be very helpful!"

"Just make sure you do the homework every week and come to every single class. If you do that you should be in pretty good shape."

Astronomy final exam question: comparing temperatures of Pollux versus Bellatrix

Astronomy 210 Final Exam, fall semester 2015
Cuesta College, San Luis Obispo, CA

Pollux is a star that is less luminous, but is larger in size than Bellatrix. Determine which star has a hotter surface temperature (or if there is a tie), and discuss how you know this. Explain using Wien's law, the Stefan-Boltzmann law and/or an H-R diagram.

Solution and grading rubric:
  • p:
    Correct. Uses Wien's law, the Stefan-Boltzmann law and/or interprets H-R diagram to demonstrate how Pollux (larger in size) must be much cooler in temperature in order to be less luminous (or vice versa, where Bellatrix (smaller in size) must be much hotter in temperature in order to be more luminous).
  • r:
    Nearly correct (explanation weak, unclear or only nearly complete); includes extraneous/tangential information; or has minor errors.
  • t:
    Contains right ideas, but discussion is unclear/incomplete or contains major errors. At least discussion demonstrates understanding of Wien's law, H-R diagram and/or the Stefan-Boltzmann law.
  • v:
    Limited relevant discussion of supporting evidence of at least some merit, but in an inconsistent or unclear manner. At least attempts to use Wien's law, H-R diagram and/or the Stefan-Boltzmann law.
  • x:
    Implementation/application of ideas, but credit given for effort rather than merit. Discussion not clearly based on Wien's law, H-R diagram and/or the Stefan-Boltzmann law.
  • y:
    Irrelevant discussion/effectively blank.
  • z:
    Blank.
Section 70158
Exam code: finalS157
p: 22 students
r: 0 students
t: 14 student
v: 0 students
x: 1 student
y: 0 students
z: 1 student

Section 70160
Exam code: finalN157
p: 12 students
r: 0 students
t: 6 student
v: 3 students
x: 1 student
y: 1 student
z: 2 students

A sample "p" response (from student 1822):

Astronomy final exam question: no mid-main-sequence line star cluster?

Astronomy 210 Final Exam, fall semester 2015
Cuesta College, San Luis Obispo, CA

The following claim was made on an online discussion board[*]:
eta: When a star cluster is very young, or when it is very old, there will be very few 
stars on the middle of the main-sequence line.
Discuss why this statement is correct (for both a very young and a very old cluster), and how you know this. Explain using the properties of mass and stellar lifetimes, evolution of stars, and star cluster ages.

[*] answers.yahoo.com/question/index?qid=20090427201220AA1weW2.

Solution and grading rubric:
  • p:
    Correct. Understands that:
    1. stars in the same cluster are all born at the same time, but massive stars evolve faster than medium-mass stars, which evolve faster than low-mass stars;
    2. for a very young star cluster, massive stars reach the main-sequence line before medium-mass stars (which are in the "middle" of the main-sequence line);
    3. for a very old star cluster, by the time low-mass stars reach the main-sequence line, medium-mass stars will have already ended their main-sequence lifetime and left the main-sequence line.
  • r:
    Nearly correct (explanation weak, unclear or only nearly complete); includes extraneous/tangential information; or has minor errors.
  • t:
    Contains right ideas, but discussion is unclear/incomplete or contains major errors. Discusses only one out of three concepts in (p) correctly, typically at least understands correlation between mass and main-sequence lifetimes.
  • v:
    Limited relevant discussion of supporting evidence of at least some merit, but in an inconsistent or unclear manner. Garbled discussion of properties and evolution of stars.
  • x:
    Implementation/application of ideas, but credit given for effort rather than merit. Discussion other than that of the properties and evolution of stars.
  • y:
    Irrelevant discussion/effectively blank.
  • z:
    Blank.
Grading distribution:
Section 70158
Exam code: finalS157
p: 11 students
r: 5 students
t: 11 students
v: 4 students
x: 3 students
y: 1 student
z: 3 students

Section 70160
Exam code: finalN157
p: 1 student
r: 4 students
t: 5 students
v: 4 students
x: 5 students
y: 2 students
z: 4 students

A sample "p" response (from student 3695), referring to the "House Party model" of stellar evolution in determining a star cluster's age:

A sample "y" response (from student 2456), who is apparently more interested on seeing the new Star Wars movie than discussing star evolution rates:

Astronomy final exam question: comparing metallicities of same-age white dwarf and red dwarf

Astronomy 210 Final Exam, fall semester 2015
Cuesta College, San Luis Obispo, CA

An astronomy question on an online discussion board[*] was asked and answered:
??: A white dwarf and a red dwarf are the same age. Which star would contain more metals inside (elements heavier than hydrogen and helium)?
DM: The white dwarf would be considered highly metallic, whereas the red dwarf would have a low metallicity.
Discuss why this answer is correct, and how you know this. Explain using the properties and evolution of stars.

[*] answers.yahoo.com/question/index?qid=20151128104746AAmtupC.

Solution and grading rubric:
  • p:
    Correct. Understands that stars of the same age were born at the same time from the same dust and gas cloud, such that they start with the same metallicity. The white dwarf is the core remnant of a medium-mass star, where all the hydrogen has already been converted to helium, and subsequently to carbon and oxygen "metals." However, a red dwarf only fuses hydrogen to helium, and does not produce more metals.
  • r:
    Nearly correct (explanation weak, unclear or only nearly complete); includes extraneous/tangential information; or has minor errors.
  • t:
    Contains right ideas, but discussion is unclear/incomplete or contains major errors. Typically claims that the white dwarf evolved faster and was born more recently than the red dwarf, thus has inherited more metals from the previous generation of stars; while the red dwarf evolves slower and was born earlier than the white dwarf, in a metal-poor, hydrogen-rich universe (despite being told that these two stars are the same age, and thus were born at the same time).
  • v:
    Limited relevant discussion of supporting evidence of at least some merit, but in an inconsistent or unclear manner. Garbled discussion of properties and evolution of stars.
  • x:
    Implementation/application of ideas, but credit given for effort rather than merit. Discussion other than that of the properties and evolution of stars.
  • y:
    Irrelevant discussion/effectively blank.
  • z:
    Blank.
Grading distribution:
Section 70158
Exam code: finalS157
p: 6 students
r: 5 students
t: 15 students
v: 6 students
x: 3 students
y: 1 student
z: 2 students

Section 70160
Exam code: finalN157
p: 3 students
r: 2 students
t: 6 students
v: 6 students
x: 5 students
y: 1 student
z: 2 students

A sample "p" response (from student 4338):

A sample "t" response (from student 1795), not recognizing that the white dwarf (end-stage of a more rapidly evolving medium-mass star) and the red dwarf (slowly evolving low-mass star) are stated to be the same age:

A sample "x" response (from student 2306), associating metal production with high temperatures and bright luminosities:

Another sample "x" response (from student 6392), discussing how stars deplete their metals as they get older:

20160112

Astronomy in-class activity: planet-hunting

Astronomy 210 In-class activity 6 v.16.01.12, spring semester 2016
Cuesta College, San Luis Obispo, CA

Students find their assigned groups of three to four students, and work cooperatively on an in-class activity worksheet to determine where in the sky each naked-eye planet will be observed on a given date (here, February 4, 2016).




Previous posts:

20160104

Online reading assignment question: advice to self for next semester

Physics 205A, fall semester 2015
Cuesta College, San Luis Obispo, CA

Students have a 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. The following question was asked after the last lecture, but prior to the final exam.

Give a piece of advice to yourself at the start of next semester on what you should do (the same, or differently) in order to succeed in Physics 205A/B (or similar science courses). (Graded for completion.)
"Create a list of priorities and stick to it. I spent a lot of time working and going to class, and I thought I deserved some breaks, but that just put me behind. I need to stay motivated and get things done before breaks."

"Keep up with reading, studying material, quizzes and exams."

"Solve more practice problems and don't be afraid to ask questions!!!"

"I should, and definitely need to, buy the book and not solely rely on the reserve copy in the library. It is not always there when needed and if I had my own, I would be able to look at the book for more problems and for research purposes to figure out how to do something. "

"Work to stay focused a little more. Be more confident in yourself. You're smarter than you think."

"Take notes on reading assignments and textbook reading, even if the material does not make any sense. Then show up to class, and add to the notes to finish any concepts that didn't make sense before. Take notes on all examples in class (this is one of the ways to study for quizzes and future midterms). Don't miss any classes, and practice, practice, practice + office hours!!"

"I think I need to read more and maybe be a little more attentive in class."

"Keep working on some problems everyday (possibly at least 3 problems a day.) "

"Read the assigned chapters, go to office hours, ask tutors for help, do worksheet problems, review assigned homework problems."

"Use the time that you would spend reading the book on studying instead and just read the blog. The reading takes a lot of valuable time that you could be working on understanding the concepts instead."

"I need to complete more practice problems and ask more questions during lectures."

"Practice the problems more and don't miss any reading assignments. Set up a really feasible schedule of when to complete each of the assignments with excess time to spare. Also, try printing all the practice quizzes and exams and keep an organized homework folder, it's easy to not keep track of homework when it's mostly online."

"Understand concepts before doing practice problems with numbers."

"In order to succeed, I will start by attending the first two weeks of class :) especially the first day where the course syllabus is explained. I will also continue to practice problems rather than only memorizing the definitions and formulas--the application of these concepts was just as important to the course as the topics/definitions themselves. I will also stop trying to hold off on handing in labs until they're perfect/I'm satisfied, and hand in what I have at the time they are due. That was a big problem for me during this course. I will continue to attend every class and practice the given homework problems, both are the main reason I felt I learned in the class...I will continue to take most of my information/practice from the lecture and blog, and use the text as a minor supplement. I will hopefully have a schedule that allows me to more easily attend office hours, and I will schedule other times if it doesn't. I will try to first learn the concepts and the applications, and then apply what I've learned to real-life situations (rather than thinking of real-life situations and assuming the concept from that). I will try to finish my homework assignments earlier in the day so I can comprehend them a bit better. I will try to not be so forgetful about online homework that is due at midnight. I will continue to study in the DSPS office--they are awesome!"

"STUDY! Never take the blog for granted!"

"I would go to more office hours if my work schedule would allow."

"Don't procrastinate, and keep up with the reading assignments and do the problems ahead of time."

"Make sure and stay on top of the material, don't wait until the night before to study! Make sure you actually understand the homework and ask for help if you don't. "

"Skim the text for concepts, then take better notes in class and work through more practice problems"

"I should study all of the problems my professor gives me because that is what lead me to succeed in this course. "

"Please don't let the easy points slide if you happen to take this class next semester."

"Do the reading assignments because this is a point-based class."

"Take better notes in class would have really helped me down the road."

"Be active about the reading assignments, read the blogs. Relax."

"This class is taught differently than others so be prepared to adjust your study habits. We are expected to learn the info, for the most part, through the provided online blogs. At first it will seem frustrating that we do not necessarily have 'lecture' in class but that is how life goes. If you do not learn to adjust to new things then you will fall behind so never expect everything to revolve around you the way you want it. When we come into class, the instructor will help you work out kinks and explain concepts that you couldn't fully comprehend on your own. Overall he is a great instructor and I have learned a good amount from taking his class. "

"Do the homework."

"I'll just keep doing what I am doing currently."

"Read more."

"Read each online presentation before class. Do the practice worksheets throughout the weeks before a quiz."

"I should learn to keep up with the current material and not cram before quizzes and tests. "

"Do all of the homework."

"Do the reading for the blog, actually sit down and schedule times to do the problems before quizzes and tests. Talk to the instructor, he'll help you schedule your schoolwork and drop some knowledge bombs on you."

"Do the damn homework. FREE POINTS!"

"Maybe do more homework problems and study more for quizzes."

"Seek extra help earlier in the semester."

"A piece of advice I would give myself is stay on campus more often because I noticed that when I stay on campus more often, I'm more likely to study in the library and review notes. Instead of going home when class is over, go to the library and study for an hour or two. That way I stay on top of the material and won't procrastinate learning the material at home."

"Go to office hours more often for help, do not be scared to ask questions in class, and balance time more wisely."