P-dog's blog: boring but important

Astronomy and physics education research and comments, field-tested think-pair-share (peer instruction) clicker questions, flashcard questions, in-class activities (lecture-tutorials), current events questions, backwards faded scaffolding laboratories, Hake gains, field-tested multiple-choice and essay exam questions, indices of discrimination, presentation slides, photos, ephemerae, astronomy in the marketplace, unrelated random sketches and minutiae.

20120331

Astronomy quiz archive: stellar evolution

Astronomy 210 Quiz 5, spring semester 2012
Cuesta College, San Luis Obispo, CA

Section 30674, version 1
Exam code: quiz05nArf

Section 30674

0- 8.0 :	* [low = 7.0]
8.5-16.0 :	*****
16.5-24.0 :	********* [mean = 23.1 +/- 6.9]
24.5-32.0 :	**************
32.5-40.0 :	*** [high = 36.5]

Section 30676, version 1
Exam code: quiz05spH3

Section 30676

0- 8.0 :	** [low = 7.0]
8.5-16.0 :	*******
16.5-24.0 :	**************** [mean = 21.2 +/- 6.8]
24.5-32.0 :	************
32.5-40.0 :	* [high = 40.0]

20120330

Physics quiz question: cold-cranking battery energy

Physics 205B Quiz 4, spring semester 2012
Cuesta College, San Luis Obispo, CA

Cf. Giambattista/Richardson/Richardson, Physics, 2/e, Problem 18.11(b), Comprehensive Problem 18.99

An Optima Yellowtop® D51 dual purpose car battery[1] is claimed to be able to provide an equivalent[2] 450 A of current at 7.2 V for 30 seconds. How much electric energy is supplied by the battery during this process?
(A) 0.48 J.
(B) 1.1×10² J.
(C) 1.9×10³ J.
(D) 9.7×10⁴ J.

Sources:
[1] http://www.optimabatteries.com/_media/documents/specs/D51_D51R.pdf.
[2] "Cold cranking amperes," http://en.wikipedia.org/wiki/Automotive_battery#Terms_and_ratings.

Correct answer: (D)

Although there are number of equations that could be used to calculate the correct answer, here a purely unit analysis method is used. Given:

450 A = 450 C/s;
7.2 V = 7.2 J/C;
30 s = 30 s.

Seeking an answer in joules, the trial solution is:

? J = (450 C/s)^a * (7.2 J/C)^b * (30 s)^c.

From inspection, the exponents a, b, and c are all unity, such that the units of C and s cancel out:

? J = (450 C/s)*(7.2 J/C)*(30 s) = 97,200 J = 9.7×10⁴ J.

Response (A) is (7.2 V)*(30 s)/(450 A); response (B) is (450 A)*(7.2 V)/(30 s); and response (C) is (450 A)*(30 s)/(7.2 V).

Section 30882
Exam code: quiz04j0uL
(A) : 3 students
(B) : 6 students
(C) : 6 students
(D) : 11 students

Success level: 42%
Discrimination index (Aubrecht & Aubrecht, 1983): 0.65

20120329

Physics quiz question: equivalent resistance of circuit

Physics 205B Quiz 4, spring semester 2012
Cuesta College, San Luis Obispo, CA

Cf. Giambattista/Richardson/Richardson, Physics, 2/e, Problem 18.41(a)

Two ideal emf sources are connected to a 24 Ω resistor, and a 1.5 Ω light bulb, as shown at right. The equivalent resistance of this circuit is:
(A) 1.4 Ω.
(B) 10 Ω.
(C) 13 Ω.
(D) 26 Ω.

Correct answer (highlight to unhide): (A)

(The two ideal emf sources are in series with each other, but with opposite polarities, such that they can be replaced with an equivalent emf source of 12 V – 3.0 V = 9 V, in the same location and orientation as the 12 V emf source.)

The two resistors are in parallel with each other, such that their equivalent resistance is given by:

R_eq = (R₁^–1 + R₂^–1)^–1,

R_eq = ((24 Ω)^–1 + (1.5 Ω)^–1)^–1 = (0.70833333333 Ω^–1)^–1 = 1.4117647059 Ω,

or to two significant figures, the equivalent resistance of this circuit is 1.4 Ω.

(Response (B) is 1.4 Ω + 9.0 V; response (C) is the average of 24 Ω and 1.5 Ω; response (D) is 24 Ω + 1.5 Ω.)

Section 30882
Exam code: quiz04j0uL
(A) : 15 students
(B) : 1 student
(C) : 0 students
(D) : 10 students

Success level: 58%
Discrimination index (Aubrecht & Aubrecht, 1983): 0.70

20120328

Physics quiz question: different charge capacitors

Physics 205B Quiz 4, spring semester 2012
Cuesta College, San Luis Obispo, CA

Cf. Giambattista/Richardson/Richardson, Physics, 2/e, Conceptual Question 17.15

Two parallel plate capacitors have the same area, and same separation gaps, but different amounts of charge. The parallel plate capacitor with the ___________ amount of charge has a greater capacitance.
(A) lesser.
(B) greater.
(C) (There is a tie.)
(D) (Not enough information is given.)

Correct answer (highlight to unhide): (C)

Both capacitors have the same area A and the same separation gap d, thus they must have the same capacitance, as seen from:

C = A/(4·π·k·d).

(However, these capacitors have different amounts of charge Q. So the capacitor with the greater amount of charge will have the greater potential difference as seen from:

ΔV = Q/C.)

Section 30882
Exam code: quiz04j0uL
(A) : 0 students
(B) : 13 students
(C) : 13 students
(D) : 0 students

Success level: 50%
Discrimination index (Aubrecht & Aubrecht, 1983): 0.35

20120327

Physics quiz archive: capacitors, circuits

Physics 205B Quiz 4, spring semester 2012
Cuesta College, San Luis Obispo, CA

Section 30882, version 1
Exam code: quiz04j0uL

Section 30882 results
Quiz 4 results (max score = 30):

0- 6 :	* [low = 6]
7-12 :	****
13-18 :	********
19-24 :	***** [mean = 20.0 +/- 6.8]
25-30 :	******** [high = 30]

20120326

Astronomy current events question: Abell 383 dark matter

Astronomy 210L, spring 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!)

Janet Anderson, Megan Watzke, "Abell 383: An Elusive Subject," March 14, 2012
http://www.nasa.gov/mission_pages/chandra/multimedia/abell383.html

Scientists are using gravitational lensing in galaxy cluster Abell 383 images to analyze the presence of its:
(A) zodiacal light.
(B) central supermassive black hole.
(C) emission and reflection nebulae.
(D) white dwarfs.
(E) dark matter.

Correct answer: (E)

Student responses
Sections 30678, 30679, 30680
(A) : 2 students
(B) : 2 students
(C) : 0 students
(D) : 1 student
(E) : 22 students

Astronomy current events question: Daya Bay Nuclear Reactor neutrino experiment

Clara Moskowitz, "Exotic Antimatter Caught in Disappearing Act," March 9, 2012
http://www.msnbc.msn.com/id/46681972/ns/technology_and_science-science/#.T3ERWWLLw0V

Measurements of transforming electron antineutrinos from nuclear reactors in China may help explain why:
(A) cold fusion is impossible.
(B) there is more matter than antimatter in the universe.
(C) recent solar flares are not as dangerous as expected.
(D) only three spatial dimensions exist.
(E) electrons have negative charge.

Correct answer: (B)

Student responses
Sections 30678, 30679, 30680
(A) : 4 students
(B) : 36 students
(C) : 5 students
(D) : 2 students
(E) : 5 students

Astronomy current events question: Ebb and Flow GRAIL spacecraft

D. C. Agle, Dwayne Brown, and Caroline McCall, "NASA's Twin GRAIL Spacecraft Begin Collecting Lunar Science Data," March 7, 2012
http://www.nasa.gov/mission_pages/grail/news/grail20120307.html

NASA's twin GRAIL mission spacecraft Ebb and Flow, orbiting the moon, have now begun collecting data to:
(A) map the moon's gravitational field.
(B) evaluate future moon base sites.
(C) find subsurface ice.
(D) measure Earth's tides.
(E) detect incoming solar flares.

Correct answer: (A)

Student responses
Sections 30678, 30679, 30680
(A) : 13 students
(B) : 1 student
(C) : 6 students
(D) : 2 students
(E) : 3 students

Astronomy current events question: avoiding zodiacal light

Francis Reddy, "NASA's Goddard, Glenn Centers Look to Lift Space Astronomy out of the Fog," March 12, 2012
http://www.nasa.gov/topics/solarsystem/features/about-next.html

To avoid interference from the zodiacal cloud of comet and asteroid dust, NASA scientists would like to place future space telescopes:
(A) mounted on high-altitude aircraft.
(B) on the far side of the moon.
(C) docked to the International Space Station.
(D) on top of Antarctic mountains.
(E) in a tilted orbit around the sun.

Correct answer: (E)

Student responses
Sections 30678, 30679, 30680
(A) : 7 students
(B) : 15 students
(C) : 5 students
(D) : 1 student
(E) : 24 students

20120323

Physics midterm question: object moved away from converging lens

Physics 205B Midterm 1, spring semester 2012
Cuesta College, San Luis Obispo, CA

Cf. Giambattista/Richardson/Richardson, Physics, 2/e, Problem 23.69

Placing an object to the left of a converging lens produces an inverted image. If the object is moved slightly farther from the lens, describe what will happen to the size of this image. Explain your reasoning by using the properties of lenses, thin lens equations and/or ray tracings.

Solution and grading rubric:

p:
Correct. Uses ray diagram or thin lens equation(s) to explain why resulting real image will be smaller when object (already outside of the primary focal point) is moved away from the converging lens.
r:
As (p), but argument indirectly, weakly, or only by definition supports the statement to be proven, or has minor inconsistencies or loopholes. May argue as p increases, m = h'/h = –d_i/d_o decreases, but does not explicitly show that q decreases as well.
t:
Nearly correct, but argument has conceptual errors, or is incomplete. Explicit use of comparative ray tracings, or thin lens equations, but instead concludes image would increase in size as object distance is increased.
v:
Limited relevant discussion of supporting evidence of at least some merit, but in an inconsistent or unclear manner.
x:
Implementation/application of ideas, but credit given for effort rather than merit.
y:
Irrelevant discussion/effectively blank.
z:
Blank.

Grading distribution:
Section 30882
Exam code: midterm01o1Ls
p: 16 students
r: 3 students
t: 5 students
v: 3 students
x: 0 students
y: 0 students
z: 0 students

A sample "p" response (from student 0524), using the thin lens equations:

A sample "p" response (from student 1123), using both ray tracings and thin lens equations:

A sample "t" response (from student 1227), using a ray tracing to show that the image size would increase:

Physics midterm question: incident angle less than critical angle

Physics 205B Midterm 1, spring semester 2012
Cuesta College, San Luis Obispo, CA

Cf. Giambattista/Richardson/Richardson, Physics, 2/e, Comprehensive Problem 23.91

A beam of light strikes the interface between vegetable oil and air with an incident angle equal to the critical angle of 42.9°, such that the beam undergoes total internal reflection. (Drawing is not to scale.) If the incident angle of the beam of light in vegetable oil is decreased slightly from 42.9° to 42.8°, describe what will happen to the beam. Explain your reasoning using the properties of light and refraction.

Solution and grading rubric:

p:
Correct. With an incident angle less than the critical angle, light will be transmitted instead of totally internally reflected (there will also be a partially reflected ray as well). Discusses definition of the critical angle, or explicitly solves for the transmitted angle in air using Snell's law.
r:
As (p), but argument indirectly, weakly, or only by definition supports the statement to be proven, or has minor inconsistencies or loopholes.
t:
Nearly correct, but argument has conceptual errors, or is incomplete.
v:
Limited relevant discussion of supporting evidence of at least some merit, but in an inconsistent or unclear manner.
x:
Implementation/application of ideas, but credit given for effort rather than merit.
y:
Irrelevant discussion/effectively blank.
z:
Blank.

Grading distribution:
Section 30882
Exam code: midterm01o1Ls
p: 21 students
r: 2 students
t: 3 students
v: 1 student
x: 0 students
y: 0 students
z: 0 students

A sample "p" response (from student 0928) appeals to the definition of the critical angle:

Another sample "p" response (from student 0801), explicitly solving for the index of refraction for cooking oil, then calculating the transmitted angle in air:

20120322

Physics midterm problem: direct wave and phase-shifted in-line reflection interference

Physics 205B Midterm 1, spring semester 2012
Cuesta College, San Luis Obispo, CA

Cf. Giambattista/Richardson/Richardson, Physics, 2/e, Problems 25.1, 25.3

[20 points.] A radio transmitter sends a signal of wavelength 0.80 km to a receiver 1.40 km away. The signal also travels from the transmitter to the receiver by another path where it reflects with a 180° phase shift from a metal skyscraper. (Drawing is not to scale.) As a result, there is a constructive signal at the receiver. Find the shortest possible (non-zero) distance between the receiver and the skyscraper. Show your work and explain your reasoning.

Solution and grading rubric:

p = 20/20:
Correct. Applies constructive interference for out-of-phase sources Δl = (m + (1/2))·λ, where path difference Δl = 2·x. Solving for the distance between the receiver and skyscraper x = (m + (1/2))·(λ/2), and setting m = 0 to find the smallest value for x = λ/4 = 0.20 km.
r = 16/20:
Nearly correct, but includes minor math errors. Sets m = 1, and finds the next smallest value for x = 0.60 km, or has Δl = x instead of 2·x.
t = 12/20:
Nearly correct, but approach has conceptual errors, and/or major/compounded math errors. At least applies correct constructive interference for out-of-phase condition.
v = 8/20:
Implementation of right ideas, but in an inconsistent, incomplete, or unorganized manner. Some attempt at connecting interference conditions to path difference.
x = 4/20:
Implementation of ideas, but credit given for effort rather than merit.
y = 2/20:
Irrelevant discussion/effectively blank.
z = 0/20:
Blank.

Grading distribution:
Section 30882
Exam code: midterm01o1Ls
p: 4 students
r: 5 students
t: 8 students
v: 4 students
x: 5 students
y: 1 student
z: 0 students

A sample "p" response (from student 6969):

Physics midterm problem: total electric field of two fixed source charges

Physics 205B Midterm 1, spring semester 2012
Cuesta College, San Luis Obispo, CA

Cf. Giambattista/Richardson/Richardson, Physics, 2/e, Multiple-Choice Question 16.10, Problem 16.35

[20 points.] Consider two point charges held at fixed locations. A –7.0 nC charge is at the origin, and a second charge (of unknown sign and amount) is at x = +0.20 m. Determine the sign (±) and amount of charge (coulombs or nC) of the second charge such the electric field is zero at x = +0.50 m. If instead this is not possible, then demonstrate why this is so. Show your work and explain your reasoning.

Solution and grading rubric:

p = 20/20:
Correct. Sets electric field of -7.0 nC charge at x = +0.50 m equal in magnitude to electric field of unknown charge at that same location. Finds magnitudes of the unknown charge, and also explicitly explains that the sign of the unknown charge must be positive.
r = 16/20:
Nearly correct, but includes minor math errors. Determination of positive sign of the unknown charge is not explained, or is negative; or explains positive sign of charge, but minor algebraic or computational errors.
t = 12/20:
Nearly correct, but approach has conceptual errors, and/or major/compounded math errors. Missing explanation of positive sign of charge, and minor computational errors.
v = 8/20:
Implementation of right ideas, but in an inconsistent, incomplete, or unorganized manner. Some attempt at finding the electric field magnitude of the -7.0 nC charge, or explaining that the unknown charge must be positive.
x = 4/20:
Implementation of ideas, but credit given for effort rather than merit. Use of force, electric potential, etc.
y = 2/20:
Irrelevant discussion/effectively blank.
z = 0/20:
Blank.

Grading distribution:
Section 30882
Exam code: midterm01o1Ls
p: 6 students
r: 10 students
t: 1 student
v: 4 students
x: 6 students
y: 0 students
z: 0 students

A sample "p" response (from student 4027):

20120321

Online reading assignment question: helpful/unhelpful Midterm 1 physics study tips

Physics 205B Online reading assignment 14, spring 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.

Describe something notable that either helped or did not help with studying for this midterm. Selected comments may be discussed in class. (Graded for completion.)

The following are all of the student responses to this question, verbatim and unedited. Some responses have been bolded for emphasis.

"the practice quizzes and midterms really help me with studying for the midterm"

"Use the questions missed on the quizes to help prepare for the mid term"

"Don't watch Netflix while studying."

"the homeworkk questions to prepare helped"

"it doesn't help to get behind in the homework and reading"

"Flashcards help a great deal with mastering the concepts."

"Going through the homework problems and flashcard questions in helpful"

"get sleep, do the suggested homework, flashcard questions"

"midterm announcements"

"I like doing the homework problems in class so it shows us different problems about the subject being learned"

"Redoing all of the old homework assignments and quizzes helps a lot."

"going over class notes really helps understand the equations in context"

"Not waiting until the night before/morning of to start studying helps quite a bit."

"going over the emphasized problems helped a lot and old quizes"

"Homework and paying attention in lecture, the book is cool and all, but it doesn't make an sense without a translator
going over problems"

"Flash card questions, the review homework over the weekend, quizes from this year and last with answers."

"None"

"Focus more on the concepts and the math should fall into place."

"practice problems"

"refer to past midterm, and notes from class"

"understanding the equations and the changes of one term that changes the other."

Online reading assignment question: interesting Midterm 1 physics topics

Physics 205B Reading Assignment 14, spring semester 2012
Cuesta College, San Luis Obispo, CA

120317-interestingwordle
http://www.flickr.com/photos/waiferx/6844308988/
Originally uploaded by Waifer X

Wordle.net tag cloud for interesting topics covered in Midterm 1, generated by responses from Physics 205B students at Cuesta College, San Luis Obispo, CA (http://www.wordle.net/show/wrdl/5022150/Untitled).

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.

List at least three words describing interesting subjects covered in class (up through this midterm). (Graded for completion.)

[Responses have been edited to consolidate related common subjects.]

Student responses
Section 30882

doubleslits interference
lasers telescopes farpoint
physics, physics, physics
refraction EMwaves refraction
polarization, lenses, raytracings
lenses, polarization, refraction
raytracings, electricfields, reflection
reflection, lenses, interference
electricity shocking
lasers, electricity doubleslits
lenses, refraction, polarization
charges, diffraction, polarization
electricfields
refraction, electricfields, potential
myopia capacitance complicated
diffraction, lenses, diffraction
polarization, lenses, electricfields
none
EMwaves, electrons, lenses
TIR reflection, lenses, raytracings
EMwaves, lenses
lenses refraction interference

Describe your most interesting subject, and briefly explain why this subject interested you. (Graded for completion.)

The following are all of the student responses to this question, verbatim and unedited.

"constructive and destructive interference. it is interesting to me that when 2 waves, such as radio waves, meet and are destructive interference then you will not hear anything"

"I enjoyed the section on snell's law, because mythbusters mentions this law , when looking at someone above ground while underwater refraction will change the image"

"Electrical fields, It has interesting effects on the migration of snake species"

"refraction emwaves snells law"

"polarization because i have polarized lenses for my camera and sunglasses."

"Lenses are super applicable to daily life."

"Optics because I now know what my optometrist is doing when I have an eye appointment"

"how a telescope works by bringing to object closer"

"electricity because it can be shocking. literally"

"Electricity with the attract and repel thing."

"the most interesting for me is lenses because it's interesting to learn how glasses, microscopes, and telescopes work.
diffraction is the most interesting b/c I think its fascinating that light+light can equal darkness"

"I picked electric fields as the most interesting subject in this midterm. Electricity as a whole fascinates me and what we have covered on the subject so far is limited."

"electric fields and electric potential were really hard for me to understand at first, but after having a few friends explain it to me, it has become one of the most interesting."

"Lenses, they look cool, and make other things look cool"

"telescopes"

"I found the subject of converging and diverging lens the most interesting because lens are everywhere in our daily life. I felt like i could relate to this material the best of any of the subjects."

"None"

"Electrons and Charges, because of the endless uses of the principle in daily modern life. Understanding the concept helps to understand a lot of other things in the modern world; well, better at least."

"I liked doing reflection and refraction"

"light passing through objects"

"i enjoy the lense applications in vision, telescopes and ray tracings"

Online reading assignment question: confusing Midterm 1 physics topics

Physics 205B Reading Assignment 14, spring semester 2012
Cuesta College, San Luis Obispo, CA

120317-confusingwordle
http://www.flickr.com/photos/waiferx/6990433347/
Originally uploaded by Waifer X

Wordle.net tag cloud for confusing topics covered in Midterm 1, generated by responses from Physics 205B students at Cuesta College, San Luis Obispo, CA (http://www.wordle.net/show/wrdl/5022184/Untitled).

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.

List at least three words describing confusing subjects covered in class (up through this midterm). (Graded for completion.)

[Responses have been edited to consolidate related common subjects.]

Student responses
Section 30882

telescopes microscopes
image plugandchug magnifiers
none
waves refraction refraction
lenses thinfilms, interference diffraction, raytracings, TIR,
electricfields, potential, capacitors
doubleslits interference, diffraction, electricpotentialenergy
capacitors, electricfields, refraction
lenses, radio, doubleslits
pathdifference radio interefernce
electricfields, electricforces, doubleslits interference
transmitter, raytracings
maxima minima
potential, electricfields, ahhhhh
capacitors voltage systems
none
interference, inphase outofphase, potential
lenses
lenses, voltage, Zerg
lenses, pathdifference, electricfields
everything
electricfields, charges

Describe your most confusing subject, and briefly explain why this subject confused you. (Graded for completion.)

The following are all of the student responses to this question, verbatim and unedited.

"the difference between the lenses in telescopes and microscopes because i still do not really understand which come up with real images and virtual images"

"I had difficulty with finding focal length."

"Electrical potential energy and its relationship to voltage. It is just more difficult then the rest to wrap your mind around a static force with flow and dynamics."

"em wave phase shift"

"thin lens/thin films because we didn't really cover it in class"

"Electric Field as they are too theoretical and not possible to visualize."

"Interference and diffraction"

"electric fields, direction of pull is misleading sometimes"

"slits. how the wave traverses after the slit."

"Constructive Destructive out of phase in phase"

"Fields are the most confusing for me. Probably just because i haven't been able to cover the homework and reading yet."

"for some reason i still have trouble with ray diagrams"

"m=maxima or minima depending on whether the problem is for single or double slit."

"everything."

"Electric fields, because they're strange"

"idlk"

"Electric Potential is by far the most confusing subject we covered but I think it's confusing because we haven't spent as much time covering this subject as the other subjects."

"None"

"Lenses, simply because the math doesn't just work itself out. You have to put in the extra effort to analyze the problems first."

"telescopes and microscopes"

"electric charges"

"Im not sure i understand completely how to calculate the magnitudes of charges"

20120320

Astronomy quiz question: electron orbital transition

Astronomy 210 Quiz 4, spring semester 2012
Cuesta College, San Luis Obispo, CA

A hydrogen atom electron can jump from energy levels 1→2 by absorbing a photon with __________ required energy.
(A) slightly more than the.
(B) the exact amount of.
(C) slightly less than the.
(D) (Two of the above choices.)
(E) (All of the above choices.)
(F) (None of the above choices.)

Correct answer: (B)

The electron must absorb a photon with the exact energy required for a given transition—no less, no more.

Section 30674
Exam code: quiz04noR3
(A) : 1 student
(B) : 27 students
(C) : 1 student
(D) : 3 students
(E) : 0 students
(F) : 0 students

"Success level": 86% (including partial credit for multiple-choice)
Discrimination index (Aubrecht & Aubrecht, 1983): 0.50

Section 30676
Exam code: quiz04sLO8
(A) : 1 student
(B) : 30 students
(C) : 1 student
(D) : 1 student
(E) : 1 student
(F) : 0 students

"Success level": 87% (including partial credit for multiple-choice)
Discrimination index (Aubrecht & Aubrecht, 1983): 0.40

20120319

Astronomy current events question: meteorite amino acids

Bill Steigerwald, "Meteorites Reveal Another Way to Make Life's Components," March 9, 2012
http://www.nasa.gov/topics/solarsystem/features/life-components.html

Scientists at NASA's Goddard Space Flight Center analyzed carbon-rich meteorites and found __________ created by high temperature chemical reactions.
(A) dark matter.
(B) amino acids.
(C) microscopic diamonds.
(D) buckyballs.
(E) chlorophyll.

Correct answer: (B)

Student responses
Sections 30678, 30679, 30680
(A) : 9 students
(B) : 37 students
(C) : 6 students
(D) : 0 students
(E) : 2 students

Astronomy current events question: exomoon search project funding

David Kipping, "Help Us Find The First Exomoon," March 2, 2012
http://www.petridish.org/projects/help-us-find-the-first-exomoon/

The "Help Us Find The First Exomoon" project is soliciting donations to purchase __________ in order to discover moons orbiting exoplanets.
(A) a brand-new space telescope.
(B) Hubble Space Telescope observing time.
(C) unused Russian radio telescopes.
(D) a dedicated supercomputer.
(E) ancient Egyptian star charts.

Correct answer: (D)

Student responses
Sections 30678, 30679, 30680
(A) : 16 students
(B) : 14 students
(C) : 4 students
(D) : 19 students
(E) : 1 student

Astronomy current events question: asteroid 2012 DA14

Phil Plait, "Cool Animation Showing Asteroid DA 14's Near Miss Next Year," March 8, 2012
http://blogs.discovermagazine.com/badastronomy/2012/03/08/cool-animation-showing-asteroid-da-14s-near-miss-next-year/

When asteroid 2012 DA14 makes it closest approach to Earth in February 2013, it will:
(A) cause higher than normal tides.
(B) disrupt GPS and cell phone communications.
(C) change its orbital path.
(D) skim across the moon's surface.
(E) develop a long, bright tail.

Correct answer: (C)

Student responses
Sections 30678, 30679, 30680
(A) : 10 students
(B) : 3 students
(C) : 38 students
(D) : 0 students
(E) : 3 students

Astronomy current events question: Milky Way disk bubbles

NASA/Jet Propulsion Laboratory press release, "Citizen Scientists Reveal a Bubbly Milky Way," March 7, 2012
http://www.spitzer.caltech.edu/news/1386-feature12-03-Citizen-Scientists-Reveal-a-Bubbly-Milky-Way

New "bubbles" created by hot, young stars in the disk of the Milky Way galaxy were discovered from NASA's Spitzer Space Telescope data by:
(A) recolorizing black and white infrared images.
(B) comparing old images from NASA's Hubble Space Telescope.
(C) asking internet volunteers to count bubbles.
(D) blocking out gamma radiation from the supermassive central black hole.
(E) using interferometry together with ground-based telescopes.

Correct answer: (C)

Student responses
Sections 30678, 30679, 30680
(A) : 8 students
(B) : 9 students
(C) : 22 students
(D) : 9 students
(E) : 6 students

Astronomy quiz question: apparent vs. absolute magnitude

Astronomy 210 Quiz 4, spring semester 2012
Cuesta College, San Luis Obispo, CA

[Version 1]
Bellatrix is a star that is located 77 parsecs away from Earth. If Bellatrix were moved to a location 10 parsecs away, its apparent magnitude m would __________, while its absolute visual magnitude M_v would __________.
(A) get dimmer; not change.
(B) get brighter; not change.
(C) not change; get dimmer.
(D) not change; get brighter.

Correct answer: (B)

The apparent magnitude of Bellatrix, which is the brightness as seen from Earth, will get brighter as it is moved closer from 77 parsecs to 10 parsecs. The absolute visual magnitude, which is the intrinsic brightness, will remain the same no matter where Bellatrix is located.

Section 30674
Exam code: quiz04noR3
(A) : 3 students
(B) : 21 students
(C) : 1 student
(D) : 7 students

"Success level": 69% (including partial credit for multiple-choice)
Discrimination index (Aubrecht & Aubrecht, 1983): 0.69

[Version 2]
Tau Ceti is a star that is located 3.7 parsecs away from Earth. If Tau Ceti were moved to a location 10 parsecs away, its apparent magnitude m would __________, while its absolute visual magnitude M_v would __________.
(A) get dimmer; not change.
(B) get brighter; not change.
(C) not change; get dimmer.
(D) not change; get brighter.

Correct answer: (A)

The apparent magnitude of Tau Ceti, which is the brightness as seen from Earth, will get dimmer as it is moved farther away from 3.7 parsecs to 10 parsecs. The absolute visual magnitude, which is the intrinsic brightness, will remain the same no matter where Tau Ceti is located.

Section 30676
Exam code: quiz04sLO8
(A) : 28 students
(B) : 1 student
(C) : 6 students
(D) : 0 students

"Success level": 82% (including partial credit for multiple-choice)
Discrimination index (Aubrecht & Aubrecht, 1983): 0.40

Previous post:

Astronomy quiz question: apparent vs. absolute magnitude
(fall semester 2010).

20120318

Astronomy quiz question: blue main-sequence star vs. blue supergiant

Astronomy 210 Quiz 4, spring semester 2012
Cuesta College, San Luis Obispo, CA

A blue main-sequence star will be ___________ compared to a blue supergiant of the same color.
(A) dimmer and smaller.
(B) dimmer and larger.
(C) brighter and smaller.
(D) brighter and larger.

Correct answer: (A).

On an H-R diagram, main-sequence stars are dimmer than supergiants of the same color (temperature); and from the Stefan-Boltzmann law:

Luminosity ∝ size x Temperature^4

the less luminous star will be smaller than a more luminous star of the same temperature.

Section 30676
Exam code: quiz04sLO8
(A) : 26 students
(B) : 2 students
(C) : 5 students
(D) : 2 students

Success level: 76% (including partial credit for multiple-choice)
Discrimination index (Aubrecht & Aubrecht, 1983): 0.50

20120317

Education research: partial credit for multiple-choice questions (PCMC) student attitudes (spring semester 2012)

Starting fall semester 2008 and continuing through spring semester 2012, Cuesta College students taking Astronomy 210 (introductory astronomy) at Cuesta College, San Luis Obispo, CA have piloted the use of partial credit for multiple-choice (PCMC) questions.

During the ninth week of instruction (after taking four multiple-choice question quizzes, and a midterm with multiple-choice questions and short-answer/essay questions), students were given the opportunity to evaluate PCMC in an online "Partial Credit for Multiple-Choice (PCMC) Survey" hosted by SurveyMonkey.com.

These are the complete survey results. Analysis will be forthcoming after more data has been compiled from future semesters. Values for the mean and standard deviations are given next to the modal response category for each question. Note that the order of questions within sections II and III were randomly scrambled for each student.

Partial Credit for Multiple-Choice Survey
Cuesta College
Astronomy 210 spring semester 2012 sections 30674, 30676
(N = 46)

I. In order to receive credit for completing this survey, 
   first enter your first and last name below:
   ____


II. Recall that for this semester there is PCMC = "partial 
    credit for multiple choice," where you can get partial 
    credit even after circling a wrong answer, if you have 
    also eliminated an incorrect answer by marking it with 
    an "x."      
      Answer the following statements which may or may not 
    describe your beliefs about PCMC in this class.      
      Because of PCMC...

II.1 ...I read questions more carefully.
1. Strongly disagree      0 : 
2. Disagree               2 : **
3. Neutral                9 : *********
4. Agree                 28 : ****************************  [3.9 +/- 0.7]
5. Strongly agree         7 : *******
     
II.2 ...I spend more time taking a test. 
1. Strongly disagree      0 : 
2. Disagree              10 : **********
3. Neutral               10 : **********
4. Agree                 22 : **********************  [3.4 +/- 0.9]
5. Strongly agree         4 : ****

II.3 ...I feel more confident about circling a correct choice.
1. Strongly disagree      1 : *
2. Disagree               4 : ****
3. Neutral               19 : *******************
4. Agree                 19 : *******************  [3.4 +/- 0.8]
5. Strongly agree         3 : ***

II.4 ...I look for incorrect choices before circling a correct choice.
1. Strongly disagree      2 : **
2. Disagree               7 : *******
3. Neutral                5 : *****
4. Agree                 25 : *************************  [3.6 +/- 1.1]
5. Strongly agree         7 : *******

III. Answer the following statements which may or may not describe 
     your beliefs about PCMC in this class.  

III.1 PCMC helped me answer test questions better.
1. Strongly disagree      0 : 
2. Disagree               3 : ***
3. Neutral               13 : *************
4. Agree                 23 : ***********************  [3.7 +/- 0.8]
5. Strongly agree         6 : ******

III.2 I would recommend using PCMC in future semesters of this class.   
1. Strongly disagree      0 : 
2. Disagree               0 : 
3. Neutral                7 : *******
4. Agree                 17 : *****************  [4.3 +/- 0.7]
5. Strongly agree        21 : *********************

III.3 Having PCMC a positive experience.
1. Strongly disagree      0 : 
2. Disagree               0 : 
3. Neutral                7 : *******
4. Agree                 24 : ************************  [4.2 +/- 0.7]
5. Strongly agree        14 : **************

III.4 Using PCMC was difficult.    
1. Strongly disagree     16 : ****************
2. Disagree              20 : ********************  [2.0 +/- 2.5]
3. Neutral                5 : *****
4. Agree                  3 : ***
5. Strongly agree         1 : *

III.5 I would identify incorrect choices even without PCMC.  
1. Strongly disagree      0 : 
2. Disagree               4 : ****
3. Neutral               12 : ************
4. Agree                 23 : ***********************  [3.7 +/- 0.8]
5. Strongly agree         6 : ******

IV. (Optional.)  Please type in any comments you may have regarding 
    the use of PCMC in this class.

The following are all of the student responses to this question, verbatim and unedited. Some responses have been bolded for emphasis.

"PCMC helps me know where im at when knowing the material."

"I like it because I feel like I have two chances to get the question right."

"I enjoying using the PCMC and would strongly encourage you to continue to use it in the future...
PCMC is a great way to give partial credit, as well as narrow answers down to the correct one."

"I like being able to get partial credit even if my answer is wrong."

"Before using PCMC in this class i would initially look for the first correct answer i saw and then go over the rest of the incorrect answers ruling them out, using PCMC is very helpful for me on questions that i am unsure about cause identifying wrong answers is never a problem."

"i like it, please continue to use it"

"... I love the opportunity PCMC gives me and how it might give me some extra points but all in all the amount given is nothing that would really benefit the overall test. Plus with your tests already a lot of the multiplication problems have options that are all alike so it intimidates me to circle an answer and then go and cross out another since i feel all are correct."

"PCMC is a great way to encourage because if you know for a fact one is wrong then you know you can at least get some points!"

"I like having this because whne the questions area little difficult it does make you go through the possibiliites more thoroughly."

"I like PCMC :)"

"The PCMC really helps narrow down a correct answer if I'm having difficulty on a question."

"You should make the correct incorrect choice worth more than 0.5 points. Maybe one point?"

"no comments"

"I think it's a great idea. Usually when we are presented with multiple choice its all or nothing. This way at least gets you somewhat closer to the answer by eliminating a wrong choice, even if you don't quite know the correct choice"

"you're the man p-dog!"

"it works"

"I like it because I can fall back on them incase I am not quite sure of an answer, but I always end up finishing the quiz or test then going back and figuring our definite wrong ones."

"PCMC was great--even if I answered incorrectly, I still could receive credit on a question without taking a 0 outright. Keep it, P-Dog!"

"I find that PCMC really helps me in determining the answer to a question that I am unsure about."

"No comment"

"It takes a little bit of the stress off of a test."

"I feel PCMC is really valuable for other students more than it is for me. I am the type of person who really studies for tests and quizzes and I dot really want to use PCMC because I want to really earn my grade from putting in the effort and studying. I also, while in the moment of taking a quiz or exam forget that I can make an x mark next to a question I am not 100 percent sure about. I think PCMC will only come in handy for me in the explanation essay portion of the exam, just in case I can't explain something in as much detail as I want."

"I think PCMC is helpful because it's extremely difficult for me to get good grades on these tests. I feel like I study for such a long time, and the material is still eluding me. PCMC makes me a little more confident that I'll hopefully at least pass the class because of the partial credit I receive. (also, I think it might be good if the tests were longer and the questions were worth more points... like 20 questions worth 2 points each- that way, grades aren't devastated if you get a couple wrong!)"

"Do we have multiple choice on the midterm too and does it use PCMC. Or is the midterm only short answer"

"i really like it because all my life i was taught by teachers that if you dont know an answer, eliminate what you know is wrong first to narrow it down. Often i can do this but still struggle with the right answer. So its nice to get partial credit for the fact that i at least somewhat get it."

"i think it is a cool concept but i feel the partial credit that you give for a x-ed out answer doesn't make a very big difference with your score."

"PCMC is a grade helper, and I super appreciate that... especially when one question is worth 4 points."

"I enjoy pcmc to help eliminate wrong answers."

"i think it is smrt but it personaly makes me second guess myself"

"i think we should get even more points for crossing an answer out"

Education research: partial credit for multiple-choice questions (PCMC) student attitudes (fall semester 2008)

Education research: partial credit for multiple-choice questions (PCMC) bibliography

Astronomy quiz question: K5 giant vs. B5 white dwarf

Astronomy 210 Quiz 4, spring semester 2012
Cuesta College, San Luis Obispo, CA

A K5 giant will be __________ compared to a B5 white dwarf.
(A) cooler and dimmer.
(B) cooler and brighter.
(C) hotter and dimmer.
(D) hotter and brighter.

Correct answer: (B).

On the OBAFGKM spectral type sequence, K-type stars are cooler than B-type stars, while on an H-R diagram, giants are brighter than white dwarfs.

Section 30674
Exam code: quiz04noR3
(A) : 6 students
(B) : 24 students
(C) : 0 students
(D) : 2 students

Success level: 77% (including partial credit for multiple-choice)
Discrimination index (Aubrecht & Aubrecht, 1983): 0.50

20120316

Astronomy quiz archive: sun/spectra/star properties

Astronomy 210 Quiz 4, spring semester 2012
Cuesta College, San Luis Obispo, CA

Section 30674, version 1
Exam code: quiz04noR3

Section 30674

0- 8.0 :
8.5-16.0 :	*** [low = 13.0]
16.5-24.0 :	*******
24.5-32.0 :	************* [mean = 26.4 +/- 6.2]
32.5-40.0 :	******** [high = 36.5]

Section 30676, version 1
Exam code: quiz04sLO8

Section 30676

0- 8.0 :
8.5-16.0 :	*** [low = 12.0]
16.5-24.0 :	******************** [mean = 22.3 +/- 6.3]
24.5-32.0 :	********
32.5-40.0 :	**** [high = 40.0]

20120315

Online reading assignment question: helpful/unhelpful Midterm 1 astronomy study tips

Astronomy 210 Reading Assignment 7, spring 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.

Describe something notable that either helped or did not help with studying for this midterm. Selected comments may be discussed in class. (Graded for completion.)

The following are all of the student responses to this question, verbatim and unedited. Some responses have been bolded for emphasis.

"The flashcard questions help me to know what is on the test."

"What helps me is going over notes and previous quizes. Also reviewing the Chapters.."

"It helps me to retake my old quizes."

"study groups really help!!"

"is there going to be a h[ai]ku on the midterm?"

"Writing good notes..."

"thinking about flash cards/ class assignments."

"I think the extra credit helped we did in class because we got to work as a group and refresh our memory."

'i like the group packets in class. its much better than working on it all by yourself because other people can help you if you're stuck."

"the midterm from last semester really helps me see what the test will be about."

"Study groups help me."

"It helped for me to go over the past reading assignment questions."

"I dont like how you waited a few weeks for us to take the midterm, now we have learned numerous other chapters that will not be tested on. Makes it harder to go back and not think about what we just did instead of topics fresh in our minds at the time."

"Looking over past quizzes."

"I like the flashcard questions just wish I had more time to review them."

"Going back and reviewing old flashcard questions"

"Google and the pictures in the book help give a great visual so i can understand how things work."

"The extra credit review and flashcard questions were very helpful."

"Being in class is what helps me the most. Sometimes google."

"The flash card questions are useful because they provide an example of what the tests are like."

"Thanks for all the information that you put out there for us!"

"Try to study & complete all the goals for this midterm!"

"One thing that helps me study for this midterm is the flashcard questions and the quiz questions. Its good because I can see what kind of format the questions will be in and it helps me review the material."

"Go over the chapters lol"

"How come you don't list the incorrect and correct answers for our quizzes to help us study?"

"Going through the book and Re-taking notes is very helpful in studying."

"dont study at my house. loud roommates, annoying cat, a pit bull that thinks its a lap dog... go to the library."

"Flash cards for the terms helped"

"What's notable is what my grade on the mid-term will be. ;)"

"reading the book does not help, it makes things more confusing."

"The answers to the quizzes help a little."

"Flash card questions help; what doesn't help is not having good notes."

"past quizzes are very helpful"

"Not studying doesn't help with studying."

"I wish we had a clear study guide handout"

"Love flashcard questions for review and practice tests, I really utilize both these tools!"

"Reading over my notes and reading over the power points we did in class online should help with the midterm"

"i guess going over the quizes and having exactly what we need to study for short answers."

"the flash cards"

"having a review before the midterm is a good idea :)"

"Flash Cards"

"Reviewing the slides we discussed in class along with looking at the flashcard questions helped me study. The flashcard questions were helpful because it made you think about quiz questions and the format they are presented in."

"II helps to have the flash card questions."

"i like that there are archives of past questions on your blog"

"shotties"

"Studying the flashcards and submitting them to P-dog for verification. Also, P-dog's prompt responses makes studying a lot more effective since the material is fresh in case you were wrong on some answers."

"It helps to know how many questions will be about each chapter and how many short answer questions there will be. It does not help to have already covered material that will not be on this midterm, like learning about chapter 5 and 6."

"flashcards for memorization."

"not studying doesnt help"

"being sick"

"well i hope last years midterm helps, im sort of banking on the same general ideas being covered"

"Going over the quizzes, reading through the book, THOROUGHLY."

"I find rereading or at least skimming over the material to be very helpful"

Online reading assignment question: confusing Midterm 1 astronomy topics

Astronomy 210 Reading Assignment 7, spring semester 2012
Cuesta College, San Luis Obispo, CA

120311-confusingwordle
http://www.flickr.com/photos/waiferx/6827191422/
Originally uploaded by Waifer X

Wordle.net tag cloud for confusing topics covered in Midterm 1, generated by responses from Astronomy 210 students at Cuesta College, San Luis Obispo, CA (http://www.wordle.net/show/wrdl/4989866/Untitled).

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.

List at least three words describing confusing subjects covered in class (up through this midterm). (Graded for completion.)

[Responses have been edited to consolidate related common subjects.]

Student responses
Sections 30674, 30676

prograde retrograde planets, diagrams, eclipses
eclipses
prograde retrograde, moon, telescopes
moonphases, rise set, eclipses
moonphases, rise set
precession, tilt, telescopes
history, moon set
history, everything, retrograde
lost dontunderstandhow
people, resolvingpower, telescopes
epicycles, tilt moonphases
spectra, blackbodyradiation, eclipses
everything
history, eveningstars, morningstars
eclipses starwheel
horizons, eveningstars, morningstars
bizarre, why, uh
telescopes, quantumleaps, spectra
planets, starwheel rise set
granules blackbodyradiation parsecs
diagrams model diagrams
telescopes, history, retrograde
telescopepowers, history, magnitudes
blueshift, parallax, orbits
confusing, difficult, what
telescopes light telescopes
blackbody radiation, history
galaxies distances sunspots
continuous, emission, absorption spectra
moon set rise
visiblelight, radiowaves, adaptive optics
sun, moon set, telescopes
eclipses, starwheel, blackbodyradiation
telescopes, telescopepowers
moon planets revolution
sun, stars, temperature, Earth rotation
telescopepowers
absorption, emission, continuous spectra
hard, toomuchinfo, lost notgrasping
math, gravity, stars
telescopes, telescopepowers, morningstars
sun, stars, magnitudes, distances
telescopes, history, laws
wavelengths, infrared, telescopes
history, moon rise set, eclipses
light spectra, wavelengths, starwheel
nothing
precession, Galileo, reflectors refractors
confusing, boring, difficult.
light wavelengths retrograde
continuous absorption spectra emission Kirchhoff'slaws
starwheel, telescopes, sun planets motion
moonphases, eclipses, circumpolar
spectra continuous emission absorption, light photons waves, blackbodyradiation

"The prograde/retrograde motion of planets confused me."

"I get confused and have difficulty explaining eclipses the telescopes. It's confusing to me."

"The most confusing was learning the rising and setting times of the moon because its hard to remember the time that goes with the phase."

"moon phases"

"the electrons jumping levels and what kind of light is given off"

"Telescopes"

"Astronomers are the most confusing subject that will be on the midterm because my memory does not work well with long lists of names with life accomplishments attached."

"For me it's about remembering all the different astronomers and what they did because I mix them up."

"im having trouble remembering which person discovered what"

"learning about the different people and what they discovered about the planets, i cant remember who did what or what some of them even did."

"Moon phases confuse me."

"Spectras, because it is difficult for me to describe and notice the different ones."

"The Astronomers, all I gotta say. Did not like that part."

"The people. I cannot remember who did what very well at all."

"Definitely have a hard time knowing when something is on the horizon or what phase the moon is at a certain time of day."

"I don't understand what you line up to figure out what stars are going to be morning and evening."

"Retrograde and prograde motions of the planets. i don't get why the planets make little circles and appear to be in the same spot."

"Shadows. The penumbra, umbra, and negative shadows are very confusing to me. I keep getting them mistaken with one another."

"The sun rising questions (in east, south east, etc). I'm not too sure how to study that."

"I was confused by which of a telescopes powers is affected by which of its dimensions."

"just being able to look at diarams and find out where the planets were supposed to be on the horizon."

"Everything about telescopes! Mainly, the different parts and what they're used for."

"The most confusing subject for me is the telescope powers. I still don't fully understand LGP, resolving, and magnification power. And how to calculate these."

"Just the scale to which the distance of space is, like between stars and galaxies. Wtf!"

"The different people and what they did."

"Learning about telescopes was very difficult because there was a lot of information to learn, and a very in-depth instrument."

"sunspots"

"I guess the sources for Kirchhoff's laws was a little confusing because it was difficult remembering which spectra came from which source."

"Moon set/ rise times."

"The most confusing subject covered so far would probably have to be telescopes and the mirrors, and lens, and everything that goes along with using one."

"Moon setting times i never understood because it was difficult because it changes."

"eclipses because I can't really tell which one is which"

"how to work the star wheel, i always mix up the am/pm times because it goes counter clockwise"

"What time the moon rises or falls will be very difficult."

"the concept of the stars sizes is confusing."

"Knowing the directions via North, South, East, and West in relation to the motions of the stars, planets, sun and moon. It's just hard to keep straight because it's so dimensional."

"The different times that you will see new moon, gibbous, crescent etc.I get a little confused on when these differences take place."

"almost everything. I am just really having trouble grasping the concepts and applying them without set notes. and i think astronomy is just such a vast subject (universe is huge and confusing!) it just gets me all scrambled up"

"the moon phases, because they are hard to memorize"

"explaining what eclipse you would see from the diagram you give us. example: fall 2011 quiz 2 question 1"

"the sun, and the three different layers."

"I am very confused by telescopes and how they are measured and work. With light-gathering power, resolving power, and magnifying power, I was mixed up and confused on how they interact with each other."

"Honestly I feel fairly confused by most the things we have been doing. I didn't get much studying done this weekend and there is a good chance I am going to fail."

"the history part, because its really hard for me to take an interest in it"

"the star wheel because I get confused on which way to hold it."

"It's not for this exam... but I still don't understand how each star has a unique-but-constant EM signature"

"The most confusing subject is getting straight who did what when it comes to proving or disproving the way the solar system works"

"I seem to have struggled with solar and lunar eclipses. I don't quite know why, its just something about them that is hard for me to fully comprehend."

"sun layers its like a big lasagna i dont get the difference"

"its hard to place the absorption emission to either the photospher chromosphere."

"anything depending on location. like what time the sun will rise and set depending on the month. anything with locating when a moon will be highest overhead, or what planets will be visible at a certian time"

"Even though it is the most interesting, I seem to of been having trouble with the phases of the moon the past few quizzes. Opening the text should and has been helping that."

"The chart the involes size temp and luminosity. I had trouble grasping how the chart works. Please do a brief review of this would greatly appreciate it."

Online reading assignment question: interesting Midterm 1 astronomy topics

Astronomy 210 Reading Assignment 7, spring semester 2012
Cuesta College, San Luis Obispo, CA

120311-interestingwordle
http://www.flickr.com/photos/waiferx/6973309449/
Originally uploaded by Waifer X

Wordle.net tag cloud for interesting topics covered in Midterm 1, generated by responses from Astronomy 210 students at Cuesta College, San Luis Obispo, CA (http://www.wordle.net/show/wrdl/4989847/Untitled).

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.

List at least three words describing interesting subjects covered in class (up through this midterm). (Graded for completion.)

[Responses have been edited to consolidate related common subjects.]

Student responses
Sections 30674, 30676

telescopes moonphases
eclipses, orbits, constellations
moonphases
telescopes, moon ellipses.
starwheel, history, moonphases
prograde retrograde
science, lightpollution, revolution
precession, absolutemagnitude, moonphases
starwheel, moonphases, telescopes
cool fun new
zodiac, gammarays, lightgatheringpower
starwheel, sun, history
precession, moonphases, turbulence
stars, moon, times
telescopes, penumbra, starwheel
moonphases, starwheel, history
stars, moon, history
epic, surprising, outofthisworld
eclipses, prograde retrograde, moonphases
stars, moon telescopes
photosphere chromosphere sunspots
zodiac Ptolemy eclipses
moonphases, eclipses, sun
moonphases, eclipses, constellations
stardistances, knowledge, lookbacktime
fascinating, boring, interesting
stars rotations tides.
blackbody radiation, telescopes
orbits sun telescopes
rotation, revolution, precession
moonphases, telescopepowers, starlocations
starwheel, absorption, lightpollution
moonphases, starwheel, scientists
moonphases, rise set, telescopepowers
retrograde planets
planets, tilt, revolution
video, misosoup, telescopes.
planets motion, moonphases, telescopes
granules, misosoup, retrograde
beautiful, simple, applicability
moon, star, gravity
moonphases, starwheel stars
stars, moon, misosoup
eclipses, moonphases, zodiac
constellations, rotation, moonphases
moonphases, constellations, telescopes
eclipses, moonphases, solarflares
light, adaptiveoptics, moonphases
solstice, retrograde, magnifyingpower
inspiring, interesting, easy
moon planets stars
precession, chainsofinference
moon, history, light
rays, telescopes, cycles
quantumleaps, transparency, HRdiagram

"Temperatures of stars, because I always wondered what colors corresponded to what temperatures."

"Phases of the Moon because it is something that we can see each night. If you have the knowledge and the understanding you will be able to give an explanation."

"I thought learning about different electromagnetic radiation was interesting because there is only a small about of wavelengths we can see."

"moon phases"

"the teleoscopes and how companies built them to fit the best situtions"

"Light Pollution"

"Precession is the most interesting concept that will be on this midterm, i find it interesting that the stars we see today rotate their relative position in the sky every 26k years."

"Learning about moon phases because now I can actually look at the moon and tell what phase it is and I'm more aware of the moon now."

"finding out that the moon isnt a planet"

"learning about revolution and the constellations. its interesting because now i know im not really aries but pisces."

"I enjoyed learning about the astronomers!!"

"Turbulence, because I was always curious to know why stars twinkle."

"The moon phases and when the moon will be in which position, sorta caught my attention."

"Star wheels! They are straight up awesome!"

"I liked learning about the phases of the moon and even though I don't have the hang ofit, I'll probably still practice it outside of this class."

"So far the moons are the most interesting subject to me. I like learning about the different phases and and figuring out what time they rise and set."

"The moon because its cool being able to look at it and actually know stuff."

"How the stars move across the sky. I really enjoy seeing which stars are visible at certain times and dates throughout the year."

"Not sure if it's the most interesting but the moon is one subject that sticks out to me. For example, whenever I see the moon, I now know what phase it is in."

"Electro magnetic radiation was interesting for me because it is simple and complicated at the same time."

"kepler's laws, interesting how he took information and came up with accurate ways of how things are without modern technology."

"I like the fact I can predict different moon cycles now! SO DOPE!"

"The most interesting subject for me was learning about the solar and lunar eclipses. I've never seen either of those so it was interesting to learn all the different aspects of both types of eclipses"

"How many galaxies there are, because its fascinating to think there might be other people."

"Phases of the moon because we have so many"

"Using the starfinder, because it's neat to find different stars and see how they change."

"star sizes/temp/luminosity, because i wanted to learn about stars most going into the class."

"i think it is the orbits of everything. it is interesting because it is very hard to understand. with all the gravity and other important causes!"

"Retrograde and prograde of planets is interesting because the way we see them compared to the background stars is really quite interesting."

"Star locations--it's an intriguing study."

"I don't really have a most interesting subject so far in this class but i believe that i will."

"The star wheel and the stars location in the sky. I found it interesting because it is useful."

"Telescope powers because it let me identify how good a telescope was."

"the astronomers, i'm interested in history"

"It was interesting that the time frame for zodiac signs shifted over the past thousand years."

"It was all interesting to me."

"Most interesting is learning about the planetary and moon motions and phases. I find it extremely relevant for all humans to understand this basic knowledge about where we live."

"The differences in temperature and distance of stars. Its cool to see what astrologists can figure out"

"the moon setting/rising/phases. I just get it because i can draw out an understandable diagram. and i find myself always naming what moon phase it is to my boyfriend when we are out at night."

"star size"

"I really like learning about the moon. It is something we see almost every night and understanding that the moon is related to months and other stuff makes it seem very relevant."

"the star formations"

"Eclipses were very interesting to me because I have seen one or two before and never understood how they worked. When we discussed them, understanding how and why they happen was very exciting and interesting to learn."

"I am most interested in the constellations."

"So far I've liked telescopes the best because I've been able to understand them the most"

"Telescopes, because you dont get to see jupiter everyday...."

"Now when I see the moon, I understand where it is in its orbit and can figure out when it will be highest overhead."

"The most interesting subject covered on this midterm is Newton's laws and how the cannon model works"

"I really liked when we talked about revolution and rotation. My neighbor is in SEAL sniper school and hes talked to me about all the elements that come into play when judging a shot. One of those elements being rotation when taking extremely long shots.
depths of space its cool how far it is"

"three interesting subjects that i learned for the midterm might not be the most intresting or important but precession the way the earth revolves around the sun, and photon energy levels moving up and down energy levels."

"i liked this history of the astronomers because i like that history is tangible and interesting"

"The most interesting subject covered in this midterm would have to be the cycles of moon phases. Interesting because no matter where you are during night, you are able to identify what stage/phase the moon is in."

"I thought it was interesting how different types of the light spectra make it through and how some do not."

20120314

Astronomy midterm question: early evening spring Big Dipper

Astronomy 210 Midterm 1, spring semester 2012
Cuesta College, San Luis Obispo, CA

[20 points.] An astronomy question on an online discussion board(*) was asked and answered:

Kory: When [is the Big Dipper] visible [for an observer] in the [n]orthern [h]emisphere?
Tina L: [T]he [B]ig [D]ipper is highest in the early evening in the spring.

Discuss whether or not this answer is correct, and how you know this. Support your answer using a diagram showing the positions of the sun, moon, Earth, and an observer on Earth.

*Source: http://answers.yahoo.com/question/index;_ylt=Amy1qc2j.2ZPKhnXSiujkkojzKIX;_ylv=3?qid=20090217172556AANBQlF.

Solution and grading rubric:

p = 20/20:
Correct. Clearly explains how the Big Dipper cannot be highest in the early evening spring sky. Specifically chooses a plausible "spring" month and "early evening" time on the starwheel and finds position of the Big Dipper is not very near the zenith, or instead places the Big Dipper near zenith, and finds that a plausible "spring" month cannot line up with an "early evening" time. Or may stretch the boundaries of "spring" months or "early evening" times to find Big Dipper near zenith, making this plausible.
r = 16/20:
Nearly correct (explanation weak, unclear or only nearly complete); includes extraneous/tangential information; or has minor errors. May indicate when the Big Dipper is highest during a non-spring, non-early evening date/time instead.
t = 12/20:
Contains right ideas, but discussion is unclear/incomplete or contains major errors. Argument based on the Big Dipper being a circumpolar constellation, such that would be visible during any night of the year, but does not address plausibility of "highest in the early evening in the spring" statement. Or vague description of "spring" months or "early evening" times, or specifies date/time such that the Big Dipper is actually at lowest point in sky.
v = 8/20:
Limited relevant discussion of supporting evidence of at least some merit, but in an inconsistent or unclear manner. Substantive discussion, but missing/problematic diagram.
x = 4/20:
Implementation/application of ideas, but credit given for effort rather than merit. Uses starwheel, but reports
inconsistent/incomplete date/time/position information.
y = 2/20:
Irrelevant discussion/effectively blank.
z = 0/20:
Blank.

Grading distribution:
Section 30676
Exam code: midterm01s0Be
p: 16 students
r: 3 students
t: 12 students
v: 10 students
x: 0 students
y: 0 students
z: 1 student

A sample "p" response (from student 1449):

Another sample "p" response (from student 1339):