20120929

Overheard: extending telescope tripod legs

Astronomy 210L, fall semester 2012
Cuesta College, San Luis Obispo, CA

(Overheard as students are setting up telescopes on tripods in astronomy lab.)

Instructor: (Noticing students kneeling on the ground, looking through the telescope on a tripod with unextended legs.) "You'll probably be more comfortable if you extend the legs on the tripod."

Student: (Watching as instructor picks up tripod to extend legs.) "I didn't know it could do that--I've never used a tripod before in my life!"

20120928

Overheard: resistance to changing group assignments

Astronomy 210, fall semester 2012
Cuesta College, San Luis Obispo, CA

(Overheard as students are finding their new group assignments at the start of lecture.)

Student: (Looking at assigned group chart.) "Do we have to be in different groups this week?"

Instructor: "You get assigned to a different group every week. Everyone does."

Student: "But I really liked the group I was in last week. Why can't we stay in our old groups?"

Instructor: "If you change groups every week, you will eventually get to meet everyone else in class. Don't you want to meet new people?"

Student: "I don't want to meet new people."

Instructor: "Who knows? You might get a new group that's even more awesome than last week's. Or are you the type of person who would rather settle for last week's group?"

Student: (Mumbling.) "There's nothing wrong with settling."

20120927

Astronomy quiz question: HESS interferometry

Astronomy 210 Quiz 3, fall semester 2012
Cuesta College, San Luis Obispo, CA

Consider two of the High Energy Stereoscopic System telescopes, located near Windhoek, Namibia. These two reflector telescopes have different diameters, and different focal lengths. These and other HESS telescopes were constructed to be spread out from each other to improve:
(A) light-gathering power.
(B) resolving power.
(C) magnifying power.
(D) (Two of the above choices.)
(E) (All of the above choices.)
(F) (None of the above choices.)

(Image credit: HESS Collaboration/Stefan Schwarzburg, http://www.mpi-hd.mpg.de/hfm/HESS/pages/press/2012/HESS_II_first_light/.)

Correct answer: (B)

Increasing the distance between telescopes creates a much larger effective diameter to increase resolving power.

Section 70158
Exam code: quiz03s3Er
(A) : 2 students
(B) : 20 students
(C) : 1 student
(D) : 7 students
(E) : 6 students
(F) : 1 student

Success level: 58% (including partial credit for multiple-choice)
Discrimination index (Aubrecht & Aubrecht, 1983): 0.50

Section 70160
Exam code: quiz03ni3R
(A) : 3 students
(B) : 17 students
(C) : 3 students
(D) : 4 student
(E) : 2 students
(F) : 0 students

Success level: 62% (including partial credit for multiple-choice)
Discrimination index (Aubrecht & Aubrecht, 1983): 0.56

Astronomy quiz archive: telescopes

Astronomy 210 Quiz 3, fall semester 2012
Cuesta College, San Luis Obispo, CA

Section 70158, version 1
Exam code: quiz03s3Er


Section 70158
0- 8.0 : * [low = 4.0]
8.5-16.0 : *********
16.5-24.0 : ************* [mean = 22.8 +/- 8.5]
24.5-32.0 : ********
32.5-40.0 : ****** [high = 40.0]


Section 70160, version 1
Exam code: quiz03ni3R


Section 70160
0- 8.0 :
8.5-16.0 : *** [low = 12.0]
16.5-24.0 : *******
24.5-32.0 : ************* [mean = 26.7 +/- 6.8]
32.5-40.0 : ****** [high = 40.0]

20120926

Online reading assignment: spectra, Doppler shift, apparent/absolute magnitude, parallax (SLO campus)

Astronomy 210, fall semester 2012
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 different types of spectra, the Doppler shift, and determining absolute magnitude of stars, given apparent magnitude and distance (from parallax).

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.
"A star is hot and dense from the inside but cool and diffuse on the outside."

"That for neon lights the red-orange color is only from the neon gas in it, was crazy. I thought it was from colored glass."

"The Doppler effect, because I always knew that sound was different going towards or away from you, and now I know why."

"Analyzing the sun's chemical composition by identifying specific spectral lines. I always wondered how astronomers could figure this out, because you can only get so close before you sizzle."

"It was interesting that corona was the name of the outermost layer of the sun's atmosphere and wondered if that was what the beer was named after. I looked it up in Spanish because the beer is from Mexico, in Spanish it means 'crown' which I think probably means yes, because the corona of the sun kind of looks like a crown."
Describe something you found confusing from the assigned textbook reading or presentation preview, and explain why this was personally confusing for you.
"The differences between the continuous, emission, and the absorption spectra still confuses me. This is confusing because emission sounds like it should be the one that gives off a lot of the spectra, but its the one that only gives off certain sections of it. While the absorption spectra gives off a lot of the spectra while it sounds like it should only give off certain sections of it."

"How to decipher which spectrum is which. I always thought there was only one spectrum of light possible."
Ask the instructor an anonymous question, or make a comment.  Selected questions/comments may be discussed in class.
"I have not yet purchased a textbook. I plan to go to the library before class tomorrow and open a book. I have never been good at school." (No comment.)

"I'm not understanding the cross-out and answer method on quizzes." (For partial-credit for multiple-choice grading, circle one response you think is the correct answer. Optionally, cross out one response you think is not the correct answer. If you did circle the correct answer, you get full credit (regardless of if/whether you crossed-out an incorrect response). If you did not circle the correct answer, you can get partial credit if you had successfully crossed-out one incorrect response.)

"Will the class material get easier, or do you have any study suggestions besides the archived quizzes from last semester?" (Download and go through the flashcard question packet as you read the textbook, especially the questions that were not asked in class. Answers to flashcard questions are not published nor released, but I would be more than willing to discuss your responses during posted office hours or an arranged appointment, just before/after lecture, or via e-mail.)

20120925

Online reading assignment: uniform circular motion

Physics 205A, fall semester 2012
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 a presentation on uniform circular motion.

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.
"Although there are many circumstances such as a merry-go-round, spinning something on a string, or even driving a motorcycle in a circle, that the basic formulas and ideas of uniform circular motion stay the same."

"The direction of acceleration for uniform circular motion is inward, rather than outward, because I have always felt a pull outward."

"As long as the tires roll without slipping, there is no relative motion between the bottom of the tires and the road, so it is the force of static friction that acts."

"Why roads are banked. If not, I would have probably been in a few accidents by now."
Describe something you found confusing from the assigned textbook reading or presentation preview, and explain why this was personally confusing for you.
"I'm having problems identifying the types of forces acting on objects, when told to draw a diagram."

"How does the acceleration go toward the center of the circle but the object is moving in a perpendicular direction, I just don't get that."

"I do not know how to explain tangential vs. radial direction."

"I kind of get the whole non-zero acceleration thing for uniform circular motion but I am still a little lost. I think my mind says if the speed is not changing acceleration should be zero."
Briefly describe the difference between the "centripetal" direction and the "centrifugal" direction.
"'Centripetal' = center-seeking direction; 'centrifugal' = center-fleeing direction."

"Centripetal is like radial, and centrifugal is like tangential."
Ask the instructor an anonymous question, or make a comment. Selected questions/comments may be discussed in class.
"Can you provide us answers for the flashcards?" (As a matter of policy, answers to flashcard questions are not published nor released, but I would be more than willing to discuss your responses to flashcard questions that were not used in class, during posted office hours or an arranged appointment, just before/after lecture, or via e-mail.)

"Can we get a list of topics that will be on each quiz/test? Or at least a list of what sections from the book we need to know?" (The study guide for each quiz or exam is always posted on the course website.)

"Sometimes I feel like I understand the material really well, and then on quizzes/flashcard questions I just don't understand anymore. :(" (This is why flashcard questions are used in class, for both students and myself as the instructor to assess what you know, and what you only thought you knew (but we can subsequently spend more time on).)

"Doing the problems step-by-step in class is really helping me. The problem-solving is what I am having a harder time with rather than the definitions." (There is only so much time that can be set aside for step-by-step examples in class, but the student solutions manual for the textbook, with many worked-out answers, is on reserve in the library.)

"Well, why is...those things? (Because...physics.)

Overheard: comparing in-class activity (lecture-tutorial) worksheet answers (2)

Astronomy 210, fall semester 2012
Cuesta College, San Luis Obispo, CA

(Overheard as student groups are completing their in-class activity (lecture-tutorial) worksheets, comparing answers with other groups as instructed before turning in their worksheets.)

Student 1: "Did you finish yet? Can we check answers with your group?"

Student 2: "No. Your group is stupid."

Online reading assignment: spectra, Doppler shift, apparent/absolute magnitude, parallax (NC campus)

Astronomy 210, fall semester 2012
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 different types of spectra, the Doppler shift, and determining absolute magnitude of stars, given apparent magnitude and distance (from parallax).

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.
"Police radar guns use the Doppler effect when measuring the speed of cars."

"The Doppler effect was pretty sweet.  Explaining how sound can be higher pitched or lower based on if the source is passing you or such, because the wavelength changes on how the source is moving."

"If light did not interact with matter we would not see things, or in fact exist at all."

"The way astronomers use triangulation to find distances of stars because it is a simple method of finding range that has been applied to a much larger scale."
Describe something you found confusing from the assigned textbook reading or presentation preview, and explain why this was personally confusing for you.
"The spectra nonsense went a little over my head.  I don't get the differences between emission lines and absorption lines."

"Absolute magnitude and apparent magnitude confused me, I don't understand their measures."
Ask the instructor an anonymous question, or make a comment.  Selected questions/comments may be discussed in class.
"How long will our midterm be?  How do I study for the midterm?" (The midterm study guide is now posted online).

"It is a little difficult reading and studying things that aren't going to be on the quiz while also trying to focus on the materials that will be on the next quiz." (Yes, but getting some lead time on the new material is still better than learning material that will immediately be on the quiz in the following class.)

"How important is it to know names of specific satellites and the date they were launched?" (Absolutely unimportant.  Always keep in mind that the emphasis of this course is on the application of astronomy concepts, rather than the rote memorization of facts and figures.)

20120924

Astronomy current events question: flash spotted on Jupiter

Astronomy 210L, fall semester 2012
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!)
Alan Boyle, "Flash Spotted on Jupiter: Is It A Hit?," September 10, 2012
http://cosmiclog.nbcnews.com/_news/2012/09/10/13789057-flash-spotted-on-jupiter-is-it-a-hit
Amateur astronomers in the U.S. recently observed a bright flash on Jupiter, which may have been caused by: (A) colliding ring particles.
(B) swirling reflective particles.
(C) a large meteor or comet impact.
(D) an energetic solar flare.
(E) massive lightning storms.

Correct answer: (C)

Student responses
Sections 70178, 70186, 70200
(A) : 2 students
(B) : 1 student
(C) : 42 students
(D) : 3 students
(E) : 6 students

Astronomy current events question: The New Solar Telescope

Astronomy 210L, fall semester 2012
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!)
Monica Young, "Sharpest Ever Images of the Sun," September 13, 2012
http://www.skyandtelescope.com/community/skyblog/newsblog/Images-of-the-Sun-Sharper-Than-Ever-169641826.html
The New Solar Telescope at Big Bear Solar Observatory uses __________ to obtain the highest resolution images ever taken of the sun.
(A) liquid nitrogen for cooling.
(B) sunlight reflected off of the moon.
(C) specialized polarizing fliters.
(D) advanced image-processing algorithms.
(E) actuators to reshape its primary mirror.

Correct answer: (E)

Student responses
Sections 70178, 70186, 70200
(A) : 0 students
(B) : 2 students
(C) : 9 students
(D) : 12 students
(E) : 30 students

Astronomy current events quiz question: Kirkwood blueberries on Mars

Astronomy 210L, fall semester 2012
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!)
Alan Boyle, "Spheres Spark New Martian Mystery," September 14, 2012
http://cosmiclog.nbcnews.com/_news/2012/09/14/13868790-spheres-spark-new-martian-mystery
The NASA Mars Science Laboratory Curiosity rover has discovered tightly packed blueberries that __________ than blueberries observed earlier by the Opportunity rover. (A) are softer and less iron-rich. (B) contain more water. (C) are larger and less blue. (D) are more radioactive. (E) contain more organic molecules.

Correct answer: (A)

Student responses
Sections 70178, 70186, 70200
(A) : 35 students
(B) : 1 student
(C) : 10 students
(D) : 2 students
(E) : 5 students

Online reading assignment: applications of Newton's laws, uniform circular motion

Physics 205A, fall semester 2012
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 a presentation on applications of Newton's laws, and uniform circular motion.

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.
"Previously I never thought of force as a push or pull force, us humans apply some kind of 'force" in order to move and lift up stuff, and put down other stuff and never thought of how we are doing a mathematical movement all of the time.  I think it is very interesting how it was described that the direction of the force is very important and the magnitude not so much, since it is not a complete description.  Also by taking in consideration all of the forces that act on an object we are describing the net force.  Vectors are very important since by adding all of them gives us the net force mentioned above."

"How complex these normal everyday situations can be broken down into extensive analysis and calculations.  I think its interesting but is also way over my head."

"Normal forces--the fact that a table is pushing back on an object to ensure that the object does not fall through the table is fascinating."

"What looks like a smooth surface of a solid to the unaided eye is actually quite rough on a microscopic scale.  Friction is caused by atomic or molecular bonds between the high points on the surfaces of the two objects.  I find it interesting that even though something might look a certain way it really is much different if you look at it more closely."

"Two objects that are in constant contact with one another but have the same velocity exert static friction forces on one another because there is no relative motion between them."

"While an object appears to rotate at a certain speed, the outside of the object is actually moving faster than the inside."

"A uniform circular motion object must always have a nonzero acceleration because the direction of velocity is continually changing.  I was originally under the impression that if an object was moving in a circle at a constant speed, it could potentially have an acceleration of zero."
Describe something you found confusing from the assigned textbook reading or presentation preview, and explain why this was personally confusing for you.
"Newton's third law, trying to wrap my mind around it."

"The normal force between two objects--is the table exerting a normal force on the book and the book is exerting normal force on table or is there only one normal force between them?"

"Pulleys. What force is going where?  Why do they split?  When will that break?"

"I found some of the trigonometry confusing cause I hate trigonometry."
Ask the instructor an anonymous question, or make a comment.  Selected questions/comments may be discussed in class.
"It is really hard to read the material and understand it before we discuss any of it in class.  I feel like I only truly pick up what we learn in lecture!" (Hopefully by reading and struggling with the material before coming to class, you're 'primed' to ask questions and be more engaged with the material when it is presented in class.)

"Do you penalize wrong answers on the online reading assignments?  After I'm done with the reading but still not sure if I get the concept as I should" (Graded for completion, as long as there is a demonstrated effort towards reading and comprehending the material.)

"What happens if you push something with the same amount of force as the kinetic friction force?" (Sounds like a Newton's first law situation, assuming that you are pushing in the same direction as motion.)

"Will you please give us more examples during class?  Everyone would benefit by taking problems from the homework, as well as the next assigned homework and working through the entire problem step-by-step."  (I always attempt to show as much problem-solving in lecture as time allows, and will allot more problem-solving time in class before quizzes and exam.  Also the student solutions manual for the textbook, with many worked-out answers, is on reserve in the library.)

"When is our first exam? Not having one for this long leads me to believe that there will be a lot of material on it and I'm a little nervous."(The first midterm is October 10, and will cover Chapters 1-5.)

20120920

Astronomy quiz question: annular solar eclipse, total lunar eclipse observer locations

Astronomy 210 Quiz 2, fall semester 2012
Cuesta College, San Luis Obispo, CA

[Version 1]
An annular solar eclipse was observed on May 2012 by observers in Northern California, who were located in:
(A) the moon's umbra.
(B) the moon's penumbra.
(C) the moon's negative shadow.
(D) Earth's umbra.
(E) Earth's penumbra.

Correct answer: (C)

The observers must be located in the moon's antumbra (or "negative shadow") to see the middle of the sun blocked, but the edges still visible.

Section 70158
Exam code: quiz02k3P7
(A) : 12 students
(B) : 10 students
(C) : 5 students
(D) : 5 students
(E) : 2 students
(More than one response) : 1 student

Success level: 19% (including partial credit for multiple-choice)
Discrimination index (Aubrecht & Aubrecht, 1983): 0.20

[Version 2]
A total lunar eclipse was observed on December 2011 by observers in San Luis Obispo, CA.  During that time, the moon was located in:
(A) Earth's umbra.
(B) Earth's penumbra.
(C) Earth's negative shadow.
(D) (none of Earth's shadow zones.)

Correct answer: (A)

During a total lunar eclipse, the moon is located entirely within Earth's umbra in order for light from the sun to be be completely blocked from reaching the moon (ignoring light scattered by Earth's atmosphere).

Section 70160
Exam code: quiz02n3Ap
(A) : 23 students
(B) : 7 students
(C) : 0 students
(D) : 1 student

Success level: 75% (including partial credit for multiple-choice)
Discrimination index (Aubrecht & Aubrecht, 1983): 0.46

Astronomy quiz question: annular solar eclipse observed from the moon

Astronomy 210 Quiz 2, fall semester 2012
Cuesta College, San Luis Obispo, CA

Consider a side view of Earth and its shadow zones, and the moon and its shadow zones.  The sun is located to the left, far off of the page.  An observer on the side of the moon facing Earth would see:


(A) the sun, with no part of it being blocked.
(B) the sun, with part of its edge being blocked.
(C) the sun, entirely blocked.
(D) the edges of the sun, with the middle of it blocked.
(E) Earth, completely illuminated by the sun.
(F) Earth, illuminated with a small circular shadow on it.
(G) Earth, completely darkened.

Correct answer: (F)

The observer is on the side of the moon facing away from the sun, so this eliminates responses (A)-(D), which would only be observed on the side of Earth (or the moon) facing the sun.  The moon's antumbra (or "negative shadow") will only mask a small portion of Earth, with the remainder of Earth remaining illuminated in the moon's penumbra (in which only a portion of the sun's disk is blocked), or outside.   (Note that this diagram is not intended to be to scale.)

Section 70158
Exam code: quiz02k3P7
(A) : 0 students
(B) : 1 student
(C) : 1 student
(D) : 0 students
(E) : 3 students
(F) : 28 students
(G) : 2 students

Success level: 81% (including partial credit for multiple-choice)
Discrimination index (Aubrecht & Aubrecht, 1983): 0.10

Section 70160
Exam code: quiz02n3Ap
(A) : 0 students
(B) : 2 students
(C) : 1 student
(D) : 1 student
(E) : 5 students
(F) : 18 students
(G) : 4 students

Success level: 61% (including partial credit for multiple-choice)
Discrimination index (Aubrecht & Aubrecht, 1983): 0.27

Astronomy quiz question: Venus/Mars at sunset?

Astronomy 210 Quiz 2, fall semester 2012
Cuesta College, San Luis Obispo, CA

Consider Earth, and the positions of other planets as shown in the diagram below (not to scale, and orbits have been simplified as circles instead of ellipses).



[Version 1]
If observers in San Luis Obispo, CA observe Venus low over the west horizon at sunset, Venus must be located at:
(A) position (A).
(B) position (B).
(C) position (C).
(D) position (D).
(E) (None of the above choices.)

Correct answer: (B)

An observer at sunset will be located at the top edge of Earth on this diagram, and a horizontal line drawn passing through the top edge of Earth corresponding to the horizon, with planet locations (A) and (B) above the horizon, and thus visible at sunset, while planet locations (C) and (D) would lie below the horizon, and thus not be visible at sunset.  Since the sun would be on the west horizon at sunset, Venus must be placed at location (B) to be just above the sun on the west horizon as well (while a planet at location (A) would be just above the east horizon at sunset.)

Section 70158
Exam code: quiz02k3P7
(A) : 6 students
(B) : 12 students
(C) : 7 students
(D) : 8 students
(E) : 2 students

Success level: 41% (including partial credit for multiple-choice)
Discrimination index (Aubrecht & Aubrecht, 1983): 0.30

[Version 2]
If observers in San Luis Obispo, CA observe Mars low over the east horizon at sunset, Mars must be located at:
(A) position (A).  
(B) position (B).
(C) position (C).
(D) position (D).
(E) (None of the above choices.)

Correct answer: (A)
An observer at sunset will be located at the top edge of Earth on this diagram, and a horizontal line drawn passing through the top edge of Earth corresponding to the horizon, with planet locations (A) and (B) above the horizon, and thus visible at sunset, while planet locations (C) and (D) would lie below the horizon, and thus not be visible at sunset.  Since the sun would be on the west horizon at sunset, Mars must be placed at location (A) to be just above the east horizon (while a planet at location (B) would be just above the sun, on the west horizon at sunset.)

Section 70160
Exam code: quiz02n3Ap
(A) : 11 students
(B) : 8 students
(C) : 10 students
(D) : 1 student
(E) : 1 student

Success level: 42% (including partial credit for multiple-choice)
Discrimination index (Aubrecht & Aubrecht, 1983): 0.06

Astronomy quiz question: Kepler's second law

Astronomy 210 Quiz 2, fall semester 2012
Cuesta College, San Luis Obispo, CA

According to Kepler's __________, a planet in an elliptical orbit will move most rapidly when it is closer the sun.
(A) first law (orbits of the planets are ellipses with the sun at one focus).
(B) second law (a line from a planet to the sun sweeps over equal areas in equal intervals in time).
(C) third law (a planet's orbital period squared is proportional to its average distance from the sun cubed).
(D) (Kepler's laws do not vary the speed of a planet along its orbit.)

Correct answer: (B)

Kepler's second law is a statement of the conservation of angular momentum, where a planet will move fastest when closest to the sun in an elliptical orbit, and move slowest when farthest from the sun.  This is analogous to the rotation of an ice skater, where the rate of rotation will increase as arms and legs are brought in closer to the body, and the rate of rotation will decrease as arms and legs are outstretched.

Section 70158
Exam code: quiz02k3P7
(A) : 7 students
(B) : 15 students
(C) : 10 students
(D) : 3 students

Success level: 46% (including partial credit for multiple-choice)
Discrimination index (Aubrecht & Aubrecht, 1983): 0.20

Section 70160
Exam code: quiz02n3Ap
(A) : 6 students
(B) : 15 students
(C) : 8 students
(D) : 2 students

Success level: 53% (including partial credit for multiple-choice)
Discrimination index (Aubrecht & Aubrecht, 1983): 0.49

Astronomy quiz archive: eclipses/history of astronomy

Astronomy 210 Quiz 2, fall semester 2012
Cuesta College, San Luis Obispo, CA

Section 70158, version 1
Exam code: quiz02k3P7

Section 70158
0- 8.0 : ** [low = 4.0]
8.5-16.0 : ***********
16.5-24.0 : ************ [mean = 19.3 +/- 7.1]
24.5-32.0 : ********
32.5-40.0 : ** [high = 33.0]


Section 70160, version 1
Exam code: quiz02n3Ap

Section 70160
0- 8.0 :
8.5-16.0 : ***** [low = 10.5]
16.5-24.0 : *****************
24.5-32.0 : ************* [mean = 24.1 +/- 7.4]
32.5-40.0 : ****** [high = 36.5]

Online reading assignment: Newton's third law

Physics 205A, fall semester 2012
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 a presentation on Newton's third law.

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 Newton's third law applies if both forces fulfill the three parts of POF-OST-ITO checklist."

"Once a system is defined all interactions can be classified as internal or external. You could define my house and the people and objects in it as an internal system, and then simply look at the rest of the forces externally."

"All interactions come in pairs."

"Newton's third law is extremely simple. :)"
Describe something you found confusing from the assigned textbook reading or presentation preview, and explain why this was personally confusing for you.
"I found the rules of free body diagrams unclear."

"Being able to remember which of Newton's laws are which and when to use which one."

"Why is it that when two equal and opposite forces act on an object that why cannot be interaction partners?"
Consider two categories of motion. (1) Velocity that is constant and unchanging. (2) Velocity that is changing. Discuss whether or not there would be a third category of motion not already covered under these two categories.
"An object at rest."

"I can't think of a situation where there would be a third category. Maybe if velocity was non-existent, but the first category pretty much covers that."
Ask the instructor an anonymous question, or make a comment. Selected questions/comments may be discussed in class.
"Can you explain the interaction partners more in-depth please. Practice problems would really help to understand the Newton's third law." (The subsequent lecture will delve into Newton's third law with many flashcard questions and examples.)

"Do we turn in late lab assignments to you or to our lab instructor?" (All laboratory work (even if late) should be handed in person directly to your laboratory instructor, submitted via e-mail, or in placed in the Physical Sciences Division mailboxes in Building 2300, or as specifically required by your laboratory instructor's policies.)

"Do you allow make-ups on the quizzes?" (No, but your three lowest (or missed) quizzes are dropped.)

"Go over more examples and homework problems, please. I wish we could go over everything we've 'learned' already. I feel I need to start from scratch. : /" (With only so much time in lecture to address concerns as suggested by student responses to the online reading assignments and homework reports, if you require additional instruction/assistance, come to posted office hours or make an appointment; ask questions just before/after lecture or via e-mail.)

"Here's a comment to say I left a comment on your 'make a comment' spot."

20120919

Physics quiz question: Usain Bolt 100 m sprint

Physics 205A Quiz 2, fall semester 2012
Cuesta College, San Luis Obispo, CA

"Leichtathletik WM 2009 Berlin"
André Zehetbauer
flic.kr/p/6RmNQn

Jamaican sprinter Usain Bolt[*] holds the world record for the 100 m sprint, covering that (straight-line) distance in 9.58 s in Berlin, 2009. Assume that his acceleration starting from rest to when he crosses the finish line is constant, and always points in the same direction as his velocity. During this race, the magnitude of his acceleration was:
(A) 1.09 m/s2.
(B) 2.18 m/s2.
(C) 10.4 m/s2.
(D) 20.9 m/s2.

[*] wki.pe/Usain_Bolt.

Correct answer (highlight to unhide): (B)

The following quantities are given (or assumed to be known):

(x0= 0 m),
(t0= 0 s),
x= +100 m,
t = 9.58 s,
v0x = 0.

So in the equations for constant acceleration motion in the horizontal direction, the following quantities are unknown, or are to be explicitly solved for:

vx = v0x + ax·t,

x = (1/2)·(vx + v0xt,

x = v0x·t + (1/2)·ax·(t)2,

vx2 = v0x2 + 2·ax·x.

With the unknown quantity ax to be solved for appearing in the third equation, with all other quantities given (or assumed to be known), then:

(1/2)·ax·(t)2 = xv0x·t,

ax = 2·x/(t)2 − 2·v0x/t,

ax = 2·(+100 m)/(9.58 s)2 − 2·(0)/(9.58 s) = +2.17920947 m/s2,

or to three significant figures (which follows from the three significant figures in 9.58 s, and assuming that the 100 m distance must be exact (or presumably measured with more precision than to the nearest meter!)), the acceleration has a magnitude of 2.18 m/s2.

(Response (A) is x/(t)2; response (C) is x/t; response (D) is 2·x/t.)

Sections 70854, 70855
Exam code: quiz02Bo74
(A) : 18 students
(B) : 23 students
(C) : 6 students
(D) : 1 student

Success level: 40%
Discrimination index (Aubrecht & Aubrecht, 1983): 0.57

Physics quiz question: average speed

Physics 205A Quiz 2, fall semester 2012
Cuesta College, San Luis Obispo, CA

The vx(t) graph of an object traveling in a straight line is shown at right. The object starts at x = 0 at t = 0. From t = 0 to t = 8 s, the average speed of the object is:
(A) 0 m/s.
(B) 0.5 m/s.
(C) 1 m/s.
(D) 3 m/s.
(E) 4 m/s.

Correct answer (highlight to unhide): (D)

Compare the definitions for the average speed, and the magnitude of average velocity:

average speed = (distance traveled)/(time elapsed ∆t),

magnitude of average velocity |vav,x| = |displacement ∆x|/(time elapsed ∆t).

Since the object travels from t = 0 to t = 8 s without changing direction, then the distance traveled would be the same as the magnitude of the displacement, and the average speed would be the same as the magnitude of average velocity.

The displacement ∆x is the area "under" the vx(t) graph (more specifically, the area bounded by the trace of the vx(t) curve, and the time axis), which is the square area from t = 0 to t = 4 s, added to the triangular area from t = 4 to t = 8 s:

x = (+4 m/s)·(4 s) + (1/2)·(+4 m/s)·(4 s) = (+16 m) + (+8 m) = +24 m.

Then the average velocity from t = 0 to t = 8 s is then:

vav,x = ∆x/∆t = (+24 m)/(8 s) = +3 m/s,

of which the magnitude, 3 m/s, is the average speed for this time interval.

Sections 70854, 70855
Exam code: quiz02Bo74
(A) : 2 students
(B) : 30 students
(C) : 4 students
(D) : 20 students
(E) : 2 students

Success level: 34%
Discrimination index (Aubrecht & Aubrecht, 1983): 0.24

Physics quiz question: upward-jumping high diver

Physics 205A Quiz 2, fall semester 2012
Cuesta College, San Luis Obispo, CA

An Olympic diver jumps upwards off of a platform and spends 1.78 s in the air until diving into the water 10.0 m below the platform[*]. Neglect air resistance. Choose up to be the +y direction. The diver jumped upwards with an initial speed of:
(A) 3.10 m/s.
(B) 5.62 m/s.
(C) 8.72 m/s.
(D) 14.34 m/s.

[*] youtu.be/9YUtFpLpGfk.

Correct answer (highlight to unhide): (A)

The following quantities are given (or assumed to be known):

(t0 = 0 s),
(y0 = 0 m),
t = 1.78 s,
y = –10.0 m,
ay = –9.80 m/s2.

So in the equations for constant acceleration motion in the vertical direction, the following quantities are unknown, or are to be explicitly solved for:

vy = v0y + ay·t,

y = (1/2)·(vy + v0yt,

y = v0y·t + (1/2)·ay·(t)2,

vy2 = v0y2 + 2·ay·y.

With the unknown quantity v0y to be solved for appearing in the third equation, with all other quantities given (or assumed to be known), then:

v0y·t = y – (1/2)·ay·(t)2,

v0y = y/t – (1/2)·ay·t,

v0y = (–10.0 m)/(1.78 s) – (1/2)·(–9.80 m/s2)·(1.78 s),

v0y = –5.62 m/s + 8.72 m/s = +3.10 m/s,

the magnitude of which is speed, or 3.10 m/s.

(Response (B) is y/t; response (C) is (1/2)·ay·t, response (D) is y/t + (1/2)·ay·t.)

Sections 70854, 70855
Exam code: quiz02Bo74
(A) : 15 students
(B) : 14 students
(C) : 10 students
(D) : 19 students

Success level: 26%
Discrimination index (Aubrecht & Aubrecht, 1983): 0.24

Overheard: comparing in-class activity (lecture-tutorial) worksheet answers (1)

Astronomy 210, fall semester 2012
Cuesta College, San Luis Obispo, CA

(Overheard as student groups are completing their in-class activity (lecture-tutorial) worksheets.)

Student 1: (Raising hand.)  "Do you want to check our answers, and see if they're correct?"

Instructor: "No, I don't want to check your answers.  I want you to compare your answers with another group."

Student 2: (Looking down the row of seats to the next nearest group.)  "They're too far away.  Why don't you check our answers?"

Instructor: <sarcasm> "If they're too far away, why don't you just take a smartphone picture of your worksheet, and post it on Facebook, saying, 'Like this if you think this is correct?'" </sarcasm>

Student 1: (Beat.) "Why don't you just check our answers?"

Physics quiz question: average speed versus (magnitude of) average velocity

Physics 205A Quiz 2, fall semester 2012
Cuesta College, San Luis Obispo, CA

Cf. Giambattista/Richardson/Richardson, Physics, 2/e, Problem 2.47

An Olympic diver jumps upwards off of a platform and spends 1.78 s in the air until diving into the water 10.0 m below the platform[*]. Neglect air resistance. Choose up to be the +y direction. As the diver travels from the platform to the water, which is the greater quantity?
(A) Average speed.
(B) Magnitude of average velocity.
(C) (There is a tie.)
(D) (Not enough information is given.)

[*] Source: Minute Physics, "Usain Bolt vs. Gravity," http://www.youtube.com/watch?v=9YUtFpLpGfk.

Correct answer: (A)

The straight-line (vertical) distance from the platform to the water is 10.0 m, which is the magnitude of the (vertical) displacementy of the diver. However, the diver traveled upwards from the platform, reaching the highest point above the platform, then traveling downwards into the water, thus the (vertical) distance traveled is greater than the magnitude of the displacement.

Comparing average speed and magnitude of average velocity:

average speed = (distance traveled)/(time elapsed ∆t),

magnitude of average velocity |vav,y| = |displacement ∆y|/(time elapsed ∆t),

since the elapsed time ∆t is 1.78 s for both quantities, then the average speed will be greater than the magnitude of the average velocity. (If the diver had traveled downwards from the platform into the water, without changing direction, then the distance traveled would be the same as the magnitude of the displacement, and the average speed would be the same as the magnitude of average velocity.)

Sections 70854, 70855
Exam code: quiz02Bo74
(A) : 28 students
(B) : 15 students
(C) : 13 students
(D) : 2 students

Success level: 48%
Discrimination index (Aubrecht & Aubrecht, 1983): 0.46

Physics quiz archive: kinematics, free fall

Physics 205A Quiz 2, fall semester 2012
Cuesta College, San Luis Obispo, CA
Sections 70854, 70855, version 1
Exam code: quiz02Bo74Sections 70854, 70855
0- 6 : ****** [low = 3]
7-12 : ****************
13-18 : ********************* [mean = 15.3 +/- 6.1]
19-24 : ***********
25-30 : **** [high = 27]

20120918

Overheard: science is hard

Astronomy 210L, fall semester 2012
Cuesta College, San Luis Obispo, CA

(Overheard while students are formulating a research question in a backwards faded scaffolding laboratory on telescope powers.)

Instructor: (Reading students' proposed research question.) "You know I don't like 'yes or no' answerable research questions, such as, 'Is science hard?'"

Student 1: "Because the answer is 'yes?'"

Instructor: (Beat.) "So, you need to ask better research questions, like, 'Why is science hard?' Or, 'What makes science so hard?' Those are the tough kinds of research questions I want you to be able to ask."

Student 2: "Because science is hard."

Astronomy current events question: IRAS 16293-2422 simple sugar molecules

Astronomy 210L, fall semester 2012
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!)
Jes K. Jørgensen, Ewine van Dishoeck, and Douglas Pierce-Price, "Sweet Result from ALMA," August 29, 2012
http://www.eso.org/public/news/eso1234/
__________ simple sugar molecules surrounding the star IRAS 16293-2422 have been detected by scientists at the Atacama Large Millimeter/submillimeter Array in Chile.
(A) Laser light reflected by.
(B) Organic life forms producing.
(C) Faint starlight passing through.
(D) Byproducts of decomposing.
(E) Radio waves emitted from.

Correct answer: (E)

Student responses
Sections 70178, 70186, 70200
(A) : 9 students
(B) : 16 students
(C) : 16 students
(D) : 13 students
(E) : 6 students

Astronomy current events question: exoplanet HD 189733b atmosphere evaporation

Astronomy 210L, fall semester 2012
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!)
NASA press release, "Hubble, Swift Detect First-Ever Changes in an Exoplanet Atmosphere," June 28, 2012
http://www.nasa.gov/topics/universe/features/exoplanet-atmosphere.html
NASA's Hubble Space Telescope observed the upper atmosphere of exoplanet HD 189733b being evaporated by _________ from its star detected by NASA's Swift satellite.
(A) a strong x-ray flare.
(B) a type II supernova explosion.
(C) intense magnetic fields.
(D) dark matter emitted.
(E) runaway heavy fusion.

Correct answer: (A)

Student responses
Sections 70178, 70186, 70200
(A) : 35 students
(B) : 7 students
(C) : 4 students
(D) : 6 students
(E) : 0 students

Astronomy current events question: Dawn spacecraft propulsion

Astronomy 210L, fall semester 2012
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!)
Jia-Rui Cook and Dwayne Brown, "NASA's Dawn Prepares for Trek Toward Dwarf Planet," August 30, 2012
http://www.nasa.gov/mission_pages/dawn/news/dawn20120830.html
The NASA Dawn spacecraft is using __________ to leave the asteroid Vesta and visit the dwarf planet Ceres:
(A) solar sails.
(B) ion propulsion thrusters.
(C) a gravitational slingshot effect.
(D) fuel harvested from Vesta's ice deposits.
(E) tidal forces from Jupiter.

Correct answer: (B)

Student responses
Sections 70178, 70186, 70200
(A) : 3 students
(B) : 43 students
(C) : 9 students
(D) : 0 students
(E) : 1 student

Online reading assignment: atmosphere problems, quantum leaps, sun's outer layers (NC campus)

Astronomy 210, fall semester 2012
Cuesta College, San Luis Obispo, CA
Section 70160 (North county campus)

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 problems caused by the atmosphere for telescope observing, quantum leaps, and the sun's outer layers.

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.
"I never knew the reason that stars twinkle is because of the atmosphere full of air. I always thought it was because of the fact that stars are giant balls of burning gas appearing to twinkle as they burn."

"The comparison between the view from underwater to the surface, and the view from Earth's surface to the sky! I personally love to lay underwater with a snorkel and look above, it looks really cool. It makes it a little easier to understand because I actually do that sometimes."

"Astronomers have to avoid society to be able to see faint stars because of light pollution and radio interference."
Describe something you found confusing from the assigned textbook reading or presentation preview, and explain why this was personally confusing for you.
"That the sun has sunspots that are cool, because you wouldn't think that something like the sun could be cool."

"Pretty much the whole section on atoms. I had difficulty seeing the correlation with everything."
Ask the instructor an anonymous question, or make a comment. Selected questions/comments may be discussed in class.
"As a 'non-sciencey' (probably not a real word) person I am having a hard time grasping some of the more technical subjects of this class. I am now spending more time on the flashcard questions, studying them on my own time, and I think that is helping me. If you have any other advice I would really appreciate it. (-:" Sounds like you are doing what many students in past semesters have suggested as being helpful. Remember that you can e-mail me about flashcard questions or other topics up until 10:00 PM the night before the quiz, and I will attempt to respond to you sometime later that night (or very early that morning).

20120917

Online reading assignment: forces and motion

Physics 205A, fall semester 2012
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 a presentation on forces and motion.

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.
"An object can have a net force of zero even when it is moving."

"No force is required to keep an object in motion if there are no forces opposing its motion. I find this statement interesting because on Earth, there is always some sort of force opposing an object, so to think that an object could go on forever without any force is incredible."

"How Newton had build so much on the works of others to form his laws."
Describe something you found confusing from the assigned textbook reading or presentation preview, and explain why this was personally confusing for you.
"How some of the laws are applied to different problems, but I think it will make more sense once you explain it in class."

"The notation of Newton's second law is confusing. The symbols are new to me."
Explain what would be the minimum (non-zero) number of forces acting on an object, such that the net force could be zero.
"Two forces acting on an object on opposite sides with equal force."

"Three, because in order for all the forces to cancel out on a graph, the tip of the last vector must end up at the tail of the first one."

"The net force could be zero with a minimum of one force acting upon the object which would be the velocity of that object.

"I can't answer this. It confuses me."
Describe the motion of an object that is moving, yet has a zero net force exerted on it.
"An object moving at a constant speed with no acceleration."

"Traveling in a straight line for eternity."

"It isn't moving...right?"
Ask the instructor an anonymous question, or make a comment. Selected questions/comments may be discussed in class.
"I couldn't think of a way that an object would have a zero net force upon it in a real-world example, wouldn't you need to be in a vacuum?" No necessarily, but the situation would have to be carefully designed to be as ideal as possible.

"Are the reading assignments graded on completion or correctness? Because I get very confused trying to sort out all of the information I read in the text, and would usually like some clarification in class about the questions asked." Graded for completion, as long as there is a demonstrated effort towards reading and comprehending the material.

"Are we always going to go this fast? Seems like a lot of complex material going by quickly." For the most part, yes. However, these reading assignments are intended to elicit feedback on the comprehension (or lack thereof) of material before coming to class, in order to adjust the level of instruction in class.

"The in-class flashcard questions are really helping me."

20120912

Online reading assignment: projectile motion, forces/interactions

Physics 205A, fall semester 2012
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 a presentation on projectile motion and forces/interactions.

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.
The demonstration in the book and the video about the two balls, one being dropped and one being shot out at the same time, because I would not have guessed for both balls to land at the exact same time. But after reading and thinking about it, it makes perfect sense."

"The horizontal velocity of a projectile does not change while it is in flight."
Describe something you found confusing from the assigned textbook reading or presentation preview, and explain why this was personally confusing for you.
"I always thought bigger objects as in mass had a greater free fall acceleration, but it's the same as small objects."

"Forces in general."
Explain what assumptions are made about the horizontal motion of an object experiencing ideal projectile motion.
"There is no air resistance on the object."

"Gravity accelerates objects downwards but does not affect horizontal motion."
Describe a situation with a negative (starting) angle of elevation for projectile motion.
"Shooting down from the top of a cliff, your angle of elevation is below the horizontal plane."

"A six-foot tall man is standing and throws a baseball at a pineapple which is two meters in front of him on the ground. The ground is not slanted."
Ask the instructor an anonymous question, or make a comment. Selected questions/comments may be discussed in class.
"Are the labs going to get harder? The first two have been very easy." (Future labs may have more than one independent parameter to be investigated, and/or non-linear dependencies between independent and dependent parameters. Also more challenging challenge activities.)

"Could you please go over a couple sample 'quiz-like' questions in class tomorrow, to gear us up for Monday's quiz? : )" (Go through last semester's quiz and discussion. You can e-mail me about the questions on the archived quiz or other topics up until 10:00 PM the night before the quiz, and I will attempt to respond to you sometime later that night (or very early that morning).)

Online reading assignment: history of astronomy, telescope powers (SLO campus)

Astronomy 210, fall semester 2012
Cuesta College, San Luis Obispo, CA
Section 70158 (San Luis Obispo campus)

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 reviewing the history of astronomy, Kepler's and Newton's laws, and telescope powers.

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.
"To think that Kepler came up with the idea of elliptical orbits and was the first to abandon the ideas of uniform and circular motion is amazing to me. I understand these theories described what is being done without actually explaining how (empirical), but I still find it fascinating that somebody is capable of 'coming up with' this stuff."

"Each progressive astronomer built from the discoveries and knowledge of those before them until they got it right. Good job guys!"

"The two most well known facts about Galileo being false. I always thought that Galileo was the one who invented the telescope and who was also the first person to look at the sky with a telescope. I also thought he was condemned for believing Earth revolved around the sun, but that was not true either."
Describe something you found confusing from the assigned textbook reading or presentation preview, and explain why this was personally confusing for you.
"I will need more time with the planets, horizons, and familiarizing myself with which planet is visible and when." (The planet-finding in-class activity from spring semester 2012 and fall semester 2011 are available if you need more practice.)

"The laws and how planets move will be confusing for me because it is sometimes hard for my brain to wrap my head around things unless I can actually see it and experiment with it."

"Trying to remember who was who was pretty tough."

"The parts of the telescope... do we need to memorize all of them and their particular functions?"
Briefly explain your answer for the most important feature [brightness/resolution/magnification] to consider when purchasing an optical telescope.
"Telescopes are made to magnify."

"Resolution, because you need to make sure the resolving power is powerful enough to see things with more detail."

"Brightness--without the image being bright the magnification doesn't matter."
Ask the instructor an anonymous question, or make a comment. Selected questions/comments may be discussed in class.
"When do we get to use the (Bowen Observatory) telescope at Cuesta?" (Tonight at the end of lecture, weather permitting.)

"Can you describe the lectures more slowly and thoroughly? I am having trouble following along in the class." (The presentations posted on my blog include all slides, and most of my comments. I will skim over certain slides, or give more explanation on certain slides depending on student responses from the online reading assignments. If you need further clarification or explanation, then come to posted office hours or make an appointment; ask questions just before/after lecture or via e-mail.)

"I really thought that I did good on the quiz and I only recieved a low C. Is there any way we could go over some questions in class off the quiz that a lot of people missed?" (Discussion of many of the quiz questions are posted on the blog.)

"How can I do better on the next quiz? :(" (Go through last semester's quiz and discussion. You can e-mail me about the questions on the archived quiz or other topics up until 10:00 PM the night before the quiz, and I will attempt to respond to you sometime later that night (or very early that morning).)

20120911

Online reading assignment: history of astronomy, telescope powers (NC campus)

Astronomy 210, fall semester 2012
Cuesta College, San Luis Obispo, CA
Section 70160 (North county campus)

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 reviewing the history of astronomy, Kepler's and Newton's laws, and telescope powers.

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.
"Kepler's laws only describe the 'how' whereas Newton's describe the 'why' of planet movement. Normally I wouldn't think of the difference between how and why planets move the way they do."

"It took so many astronomers making breakthroughs to get modern astronomy where it is."

"The two most well known facts about Galileo being false. I always thought that Galileo was the one who invented the telescope and who was also the first person to look at the sky with a telescope. I also thought he was condemned for believing the earth revolved around the sun, but that was not true either."
Describe something you found confusing from the assigned textbook reading or presentation preview, and explain why this was personally confusing for you.
"I will need more time with the planets, horizons, and familiarizing myself with which planet is visible and when." (The planet-finding in-class activity from spring semester 2012 and fall semester 2011 are available if you need more practice.)

"Even though we went over it in class, I still found retrograde to still be confusing. The textbook didn't exactly tell you how it worked, just the fact it performs illusions with the planets."

"I found it difficult to keep straight which astronomers did what! I mean there were seven of them."

"The parts of the telescope...do we need to memorize all of them and their particular functions?"
Briefly explain your answer for the most important feature [brightness/resolution/magnification] to consider when purchasing an optical telescope.
"Telescopes are made to magnify."

"Resolution, because you need to make sure the resolving power is powerful enough to see things with more detail."

"Brightness--without the image being bright the magnification doesn't matter."
Ask the instructor an anonymous question, or make a comment. Selected questions/comments may be discussed in class.
"Thank you, for being patient and always willing to help your students. I know astronomy isn't my strongest topic but you make me want to learn and understand at least the basics of my surroundings..."

"Can you describe the lectures more slowly and thoroughly? I am having trouble following along in the class." (The presentations posted on my blog include all slides, and most of my comments. I will skim over certain slides, or give more explanation on certain slides depending on student responses from the online reading assignments. If you need further clarification or explanation, then come to posted office hours or make an appointment; ask questions just before/after lecture or via e-mail.)

"How can I do better on the next quiz? :(" (Go through last semester's quiz and discussion. You can e-mail me about the questions on the archived quiz or other topics up until 10:00 PM the night before the quiz, and I will attempt to respond to you sometime later that night (or very early that morning).)

20120910

Tweet: moon phase "time" questions killing sense of wonder?


Interesting midterm 1 topics (Astr 210 students, spring semester 2011):
Confusing midterm 1 topics (Astr 210 students, spring semester 2011):