P-dog's blog: boring but important

20100611

Astronomy final exam question: runaway greenhouse or runaway refrigerator

Astronomy 210 Final Exam, Spring Semester 2010
Cuesta College, San Luis Obispo, CA

[Version 1]

[20 points.] If tectonic plate motion continued on Earth (but volcanic activity stopped), discuss how it would either become a runaway refrigerator (like Mars), or a runaway greenhouse (like Venus). Explain using properties of the geological/atmospheric cycles of planets.

Solution and grading rubric:

p = 20/20:
Correct. Ceasing volcanic activity means no carbon dioxide released back from the mantle into the atmosphere, while tectonic plate motion continues to subduct carbon dioxide in ocean sediments back into the mantle, decreasing the greenhouse effect and causing cooler temperatures. (The runaway refrigerator effect is when it is cold enough for the oceans to freeze, such that water vapor (also a greenhouse gas) is no longer present in the atmosphere, and thus even colder temperatures will take place; this much detail is not required as long as the lack of source, and continued sink in the carbon cycle are both mentioned.)
r = 16/20:
Nearly correct (explanation weak, unclear or only nearly complete); includes extraneous/tangential information; or has minor errors. Discusses lack of source and continued sink, but one of these is slightly problematic.
t = 12/20:
Contains right ideas, but discussion is unclear/incomplete or contains major errors. Typically discusses lack of source, but not continued sink.
v = 8/20:
Limited relevant discussion of supporting evidence of at least some merit, but in an inconsistent or unclear manner. Lack of heat from volcanoes that would otherwise maintain warm atmospheric temperatures, or other factors.
x = 4/20:
Implementation/application of ideas, but credit given for effort rather than merit.
y = 2/20:
Irrelevant discussion/effectively blank.
z = 0/20:
Blank.

Grading distribution:
Section 30674
p: 8 students
r: 9 students
t: 6 students
v: 14 students
x: 1 student
y: 2 students
z: 0 students

A sample "p" response (from student 8479):

A sample "r" response (from student 2569), with no discussion on carbon dioxide intake by oceans (and subsequent subduction of carbon-bearing sediments down into the mantle):

A sample "v" response (from student 7109), touching upon end of plant life and nuclear winter scenarios:

A sample "y" response (from student 0000), with a fanciful illustration:

[Version 2]

[20 points.] If tectonic plate motion stopped on Earth (but volcanic activity continued), discuss how it would either become a runaway refrigerator (like Mars), or a runaway greenhouse (like Venus). Explain using properties of the geological/atmospheric cycles of planets.

Solution and grading rubric:

p = 20/20:
Correct. Tectonic plate motion ceasing to subduct carbon dioxide in ocean sediments back into the mantle, and continuing volcanic activity releasing carbon dioxide from the mantle into the atmosphere would increase the greenhouse
effect and causing warmer temperatures. (The _runaway_ greenhouse effect is when it becomes warm enough for the oceans to evaporate, such that water vapor (also a greenhouse gas) is now prevalent in the atmosphere, and thus even hotter temperatures will take place; this much detail is not required as long as the lack of sink, and continued source in the carbon cycle are both mentioned.)
r = 16/20:
Nearly correct (explanation weak, unclear or only nearly complete); includes extraneous/tangential information; or has minor errors. Discusses lack of sink and continued source, but one of these is slightly problematic.
t = 12/20:
Contains right ideas, but discussion is unclear/incomplete or contains major errors. Typically discusses continued source, but not lack of sink.
v = 8/20:
Limited relevant discussion of supporting evidence of at least some merit, but in an inconsistent or unclear manner. Heat from volcanoes would directly cause warm atmospheric temperatures, or other factors.
x = 4/20:
Implementation/application of ideas, but credit given for effort rather than merit.
y = 2/20:
Irrelevant discussion/effectively blank.
z = 0/20:
Blank.

Grading distribution:
Section 30676
p: 6 students
r: 6 students
t: 13 students
v: 26 students
x: 12 students
y: 4 students
z: 1 student

A sample "p" response (from student 9998):

A sample "v" response (from student 3455), taking into consideration the heat produced by friction between moving tectonic plates:

A sample "x" response (from student 5611), using uppercase to underscore the importance of convection:

A sample "y" response (from student 4000):

20100610

Astronomy final exam question: absolute visual magnitude, apparent magnitude, and star distances

Astronomy 210 Final Exam, Spring Semester 2010
Cuesta College, San Luis Obispo, CA

[Version 1]

[20 points.] Star A has an apparent magnitude m = –1.0, and star B has an apparent magnitude m = +1.0. Discuss how stars A and B are located from Earth, if they have the same absolute visual magnitude M_V = +1.0. Explain using the relationships between apparent magnitude, absolute magnitude, and distance.

Solution and grading rubric:

p = 20/20:
Correct. Distinguishes apparent magnitude (brightness as seen at actual distance from Earth) from absolute magnitude (brightness as seen from 10 pcs away from Earth). Both stars have the same absolute magnitude, while star B has the same apparent and absolute magnitude, meaning that it is located exactly 10 pcs away from Earth. Star A has an apparent magnitude brighter than its absolute magnitude (as well as brighter than star B's apparent magnitude), thus star A is located closer than 10 pcs from Earth.
r = 16/20:
Nearly correct (explanation weak, unclear or only nearly complete); includes extraneous/tangential information; or has minor errors. As (p), with star A closer than star B, but does not explicitly place star B 10 pcs from Earth.
t = 12/20:
Contains right ideas, but discussion is unclear/incomplete or contains major errors. As (p), but with star B farther than star A, typically due to misinterpreting -1.0 as being dimmer than +1.0, or with star B explicitly placed at 10 pcs away from Earth.
v = 8/20:
Limited relevant discussion of supporting evidence of at least some merit, but in an inconsistent or unclear manner. At least understands distinction between apparent and absolute magnitudes, and/or that star A has a brighter apparent magnitude than its absolute magnitude.
x = 4/20:
Implementation/application of ideas, but credit given for effort rather than merit.
y = 2/20:
Irrelevant discussion/effectively blank.
z = 0/20:
Blank.

Grading distribution:
Section 30674
p: 18 students
r: 12 students
t: 6 students
v: 4 students
x: 0 students
y: 0 students
z: 0 students

A sample "p" response (from student 1802):

Another sample "p" response (from student 2615):

Yet another sample "p" response (from student 5239):

A sample "t" response (from student 1984):

[Version 2]

[20 points.] Star A has an absolute visual magnitude M_V = –1.0, and star B has an absolute visual magnitude M_V = +1.0. Discuss how stars A and B are located from Earth, if they have the same apparent magnitude m = +1.0. Explain using the relationships between apparent magnitude, absolute magnitude, and distance.

Solution and grading rubric:

p = 20/20:
Correct. Distinguishes apparent magnitude (brightness as seen at actual distance from Earth) from absolute magnitude (brightness as seen from 10 pcs away from Earth). Both stars have the same apparent magnitude, while star B has the same apparent and absolute magnitude, meaning that it is located exactly 10 pcs away from Earth. Star A has an absolute visual magnitude brighter than its apparent magnitude (as well as brighter than star B's absolute visual magnitude magnitude), thus star A is located farther than 10 pcs from Earth.
r = 16/20:
Nearly correct (explanation weak, unclear or only nearly complete); includes extraneous/tangential information; or has minor errors. As (p), with star A farther than star B, but does not explicitly place star B 10 pcs from Earth.
t = 12/20:
Contains right ideas, but discussion is unclear/incomplete or contains major errors. As (p), but with star A closer than star B, typically due to misinterpreting -1.0 as being dimmer than +1.0, or with star B explicitly placed at 10 pcs away from Earth.
v = 8/20:
Limited relevant discussion of supporting evidence of at least some merit, but in an inconsistent or unclear manner. At least understands distinction between apparent and absolute magnitudes, and/or that star A has a brighter apparent magnitude than its absolute magnitude.
x = 4/20:
Implementation/application of ideas, but credit given for effort rather than merit.
y = 2/20:
Irrelevant discussion/effectively blank.
z = 0/20:
Blank.

Grading distribution:
Section 30676
p: 12 students
r: 13 students
t: 10 students
v: 11 students
x: 21 students
y: 1 student
z: 0 students

A sample "p" response (from student 1337):

Another sample "p" response (from student 8065):

A sample "t" response (from student 1105), with star A being correctly placed more than 10 parsecs away from Earth, but star B being placed closer than 10 parsecs away from Earth, despite having absolute visual magnitude and apparent magnitude values:

A sample "v" response (from student 1559):

A sample "x" response (from student 4337), with M_V = -1 and M_V = +1 being equally spaced on either side of M_V on a number line:

Another sample "x" response (from student 5221), with star A (M_V = -1) and star B (M_V = +1) being equally distant on either side of Earth:

20100609

Education research: ALLS pre- to post-instruction attitude shifts (Cuesta College, Spring Semester 2010)

Student attitudes are assessed using an Astronomy Laboratory Learning Survey (ALLS), a five-point Likert scale questionnaire with demographic questions, and entry/exit evaluation questions (Patrick M. Len, in development) to Astronomy 210L students at Cuesta College, San Luis Obispo, CA. This laboratory course is a one-semester, adjunct course to Astronomy 210 lecture, and is taken primarily by students to satisfy their general education science laboratory transfer requirement.

The ALLS is administered as a pre-test on the first laboratory meeting, before any introduction/instruction took place; and as a post-test on the last laboratory meeting.

The results from the pre- and post-test questions follow below. Values for the mean and standard deviations are given next to the modal response category for each question, along with a Student t-test for the probability of null hypothesis rejection, and the class-wise Hake gain. (Matched-pair Hake gains were not calculated for each student, as pre-instruction values such as "5" would result in undefined values.) For statistical purposes, blank entries were treated as "3. Neutral," and multiply-circled entries such as "12," "23," "34," and "45" were treated as "1," "2," "4," and "5" respectively.

Cuesta College
Astronomy Laboratory Learning Survey (ALLS) 
Pre- and post-instruction results
Astronomy 210L Spring Semester 2010 sections 30678, 30679, 30680, 30682

1. I am interested in using a telescope or binoculars for astronomy.
Pre-instruction
1. Strongly disagree      4 : ****
2. Disagree               5 : *****
3. Neutral               16 : ****************
4. Agree                 23 : ***********************  [3.7 +/- 1.1]
5. Strongly agree        19 : *******************

Post-instruction
1. Strongly disagree      1 : *
2. Disagree               2 : **
3. Neutral                9 : *********
4. Agree                 39 : ***************************************  [4.0 +/- 0.8]
5. Strongly agree        16 : ****************

Student t-test p = 0.097 (t = -1.67, sd = 0.983, dof = 132)
Class-wise <g> = +0.22

2. Astronomy has little relation to what I experience in the real world.
Pre-instruction
1. Strongly disagree      8 : ********
2. Disagree              28 : ****************************  [2.4 +/- 0.8]
3. Neutral               25 : *************************
4. Agree                  6 : ******
5. Strongly agree         0 :

Post-instruction
1. Strongly disagree     15 : ***************
2. Disagree              23 : ***********************  [2.4 +/- 1.1]
3. Neutral               20 : ********************
4. Agree                  6 : ******
5. Strongly agree         3 : ***

Student t-test p = 0.79 (t = 0.271, sd = 0.955, dof = 132)
Class-wise <g> = -0.02

3. I know where and how to look up astronomy information.
Pre-instruction
1. Strongly disagree      6 : ******
2. Disagree              21 : *********************
3. Neutral               22 : **********************  [2.8 +/- 1.1]
4. Agree                 14 : **************
5. Strongly agree         4 : ****

Post-instruction
1. Strongly disagree      0 : 
2. Disagree               9 : *********
3. Neutral                8 : ********
4. Agree                 38 : **************************************  [4.2 +/- 0.6]
5. Strongly agree        21 : *********************

Student t-test p < 0.0001 (t = -9.05, sd = 0.869, dof = 132)
Class-wise <g> = +0.63

4. I know where and how to find objects in the night sky.
Pre-instruction
1. Strongly disagree      7 : *******
2. Disagree              20 : ********************
3. Neutral               23 : ***********************  [2.8 +/- 1.0]
4. Agree                 15 : ***************
5. Strongly agree         2 : **

Post-instruction
1. Strongly disagree      0 : 
2. Disagree               2 : **
3. Neutral                7 : *******
4. Agree                 44 : ********************************************  [4.0 +/- 0.7]
5. Strongly agree        14 : **************

Student t-test p < 0.0001 (t = -8.59, sd = 0.855, dof = 132)
Class-wise <g> = +0.57

5. I am interested in news that is related to astronomy.
Pre-instruction
1. Strongly disagree      1 : *
2. Disagree               6 : ******
3. Neutral               22 : **********************
4. Agree                 29 : *****************************  [3.6 +/- 0.79]
5. Strongly agree         9 : *********

Post-instruction
1. Strongly disagree      0 : 
2. Disagree               6 : ******
3. Neutral               23 : ***********************
4. Agree                 24 : ************************  [3.7 +/- 0.9]
5. Strongly agree        14 : **************

Student t-test p = 0.50 (t = -0.673, sd = 0.899, dof = 132)
Class-wise <g> = +0.07

6. I often ask myself questions related to astronomy.
Pre-instruction
1. Strongly disagree      5 : *****
2. Disagree              11 : ***********
3. Neutral               16 : ****************
4. Agree                 30 : ******************************  [3.3 +/- 1.1]
5. Strongly agree         5 : *****

Post-instruction
1. Strongly disagree      3 : ***
2. Disagree               9 : *********
3. Neutral               26 : **************************  [3.3 +/- 1.0]
4. Agree                 23 : ***********************
5. Strongly agree         6 : ******

Student t-test p = 0.93 (t = -0.0846, sd = 1.02, dof = 132)
Class-wise <g> = +0.009

7. I am comfortable using a calculator to make complex calculations.
Pre-instruction
1. Strongly disagree      0 : 
2. Disagree               8 : ********
3. Neutral               14 : **************
4. Agree                 30 : ******************************  [3.8 +/- 0.9]
5. Strongly agree        15 : ***************

Post-instruction
1. Strongly disagree      1 : *
2. Disagree               6 : ******
3. Neutral                9 : *********
4. Agree                 30 : ******************************  [4.0 +/- 1.0]
5. Strongly agree        21 : *********************

Student t-test p = 0.28 (t = -1.086, sd = 0.955, dof = 132)
Class-wise <g> = +0.15

8. I can make sense of equations and scientific notation numbers.
Pre-instruction
1. Strongly disagree      0 : 
2. Disagree               6 : ******
3. Neutral               21 : *********************
4. Agree                 32 : ********************************  [3.6 +/- 0.8]
5. Strongly agree         8 : ********

Post-instruction
1. Strongly disagree      0 : 
2. Disagree               7 : *******
3. Neutral               16 : ****************
4. Agree                 29 : *****************************  [3.8 +/- 0.9]
5. Strongly agree        15 : ***************

Student t-test p = 0.32 (t = -0.996, sd = 0.867, dof = 132)
Class-wise <g> = +0.11

9. I prefer to work independently rather than in groups.
Pre-instruction
1. Strongly disagree      7 : *******
2. Disagree              22 : **********************
3. Neutral               28 : ****************************  [2.7 +/- 1.0]
4. Agree                  6 : ******
5. Strongly agree         4 : ****

Post-instruction
1. Strongly disagree     14 : **************
2. Disagree              22 : **********************
3. Neutral               24 : ************************  [2.4 +/- 1.1]
4. Agree                  3 : ***
5. Strongly agree         4 : ****

Student t-test p = 0.15 (t = 1.43, sd = 1.03, dof = 132)
Class-wise <g> = -0.11

10. I can understand difficult concepts better if I am able to explain them 
to others.
Pre-instruction
1. Strongly disagree      2 : **
2. Disagree               6 : ******
3. Neutral               23 : ***********************
4. Agree                 27 : ***************************  [3.5 +/- 0.9]
5. Strongly agree         9 : *********

Post-instruction
1. Strongly disagree      0 : 
2. Disagree               5 : *****
3. Neutral               18 : ******************
4. Agree                 31 : *******************************  [3.8 +/- 0.8]
5. Strongly agree        13 : *************

Student t-test p = 0.10 (t = -1.64, sd = 0.898, dof = 132)
Class-wise <g> = +0.17

11. I can understand difficult concepts better if I am able to ask lots of 
questions.
Pre-instruction
1. Strongly disagree      0 : 
2. Disagree               1 : *
3. Neutral               16 : ****************
4. Agree                 34 : **********************************  [4.0 +/- 0.7]
5. Strongly agree        16 : ****************

Post-instruction
1. Strongly disagree      0 : 
2. Disagree               1 : *
3. Neutral               12 : ************
4. Agree                 32 : ********************************  [4.1 +/- 0.7]
5. Strongly agree        22 : **********************

Student t-test p = 0.25 (t = -1.16, sd = 0.744, dof = 132)
Class-wise <g> = +0.15

12. Knowledge in astronomy consists of many pieces of information each of which 
applies primarily to a specific situation.
Pre-instruction
1. Strongly disagree     0 : 
2. Disagree              3 : ***
3. Neutral              41 : *****************************************  [3.3 +/- 0.6]
4. Agree                21 : *********************
5. Strongly agree        2 : **

Post-instruction
1. Strongly disagree      1 : *
2. Disagree               6 : ******
3. Neutral               24 : ************************
4. Agree                 28 : ****************************  [3.5 +/- 0.9]
5. Strongly agree         8 : ***

Student t-test p = 0.11 (t = -1.60, sd = 0.756, dof = 132)
Class-wise <g>> = +0.13

13. I am good at math.
Pre-instruction
1. Strongly disagree      6 : ******
2. Disagree              10 : **********
3. Neutral               20 : ********************
4. Agree                 27 : ***************************  [3.2 +/- 1.1]
5. Strongly agree         4 : ****

Post-instruction
1. Strongly disagree      5 : *****
2. Disagree              10 : **********
3. Neutral               22 : **********************  [3.3 +/- 1.1]
4. Agree                 22 : **********************
5. Strongly agree         8 : ********

Student t-test p = 0.69 (t = 0.400, sd = 1.08, dof = 132)
Class-wise <g> = +0.04

14. I am good at science.
Pre-instruction
1. Strongly disagree      3 : ***
2. Disagree               6 : ******
3. Neutral               41 : *****************************************  [3.1 +/- 0.8]
4. Agree                 15 : ***************
5. Strongly agree         2 : **

Post-instruction
1. Strongly disagree      5 : *****
2. Disagree               7 : *******
3. Neutral               29 : *****************************  [3.2 +/- 1.0]
4. Agree                 22 : **********************
5. Strongly agree         4 : ****

Student t-test p = 0.56 (t = -0.587, sd = 0.882, dof = 132)
Class-wise <g> = 0.05

15. This course will be/was difficult for me.
Pre-instruction
1. Strongly disagree      1 : *
2. Disagree              16 : ****************
3. Neutral               34 : **********************************  [3.0 +/- 0.8]
4. Agree                 14 : **************
5. Strongly agree         2 : **

Post-instruction
1. Strongly disagree     13 : *************
2. Disagree              21 : *********************  [2.5 +/- 1.1]
3. Neutral               19 : *******************
4. Agree                  3 : ***
5. Strongly agree         1 : *

Student t-test p = 0.0039 (t = 2.94, sd = 0.940, dof = 132)
Class-wise <g> = -0.24

No statistically significant (p > 0.05) shift was observed for the slight positive shift in interest in using telescopes/binoculars in astronomy (question 1); notably there was a statistically significant (p < 0.05) downward shift in Fall Semester 2009!

Also not statistically significant (p > 0.05) shifts were observed for relating astronomy to personal experience (question 2), interest in astronomy-related news (question 5), pondering astronomy-related questions (question 6), self-efficacy in use of calculators and math in astronomy (questions 7 and 8), individual/group learning habits (questions 9, 10, 11, and 12), and self-efficacy in math/science (questions 13 and 14).

However, there are statistically significant (p < 0.05) gains in being able to find astronomy-related news/information (question 3), finding night sky objects (question 4), and rating the expected/experience difficulty of this course (question 15). The first two of these positive self-reported shifts correlate well with two of the student learning outcomes for this course:

Keep abreast of present-day discoveries and developments in astronomy (current events).
Construct and use devices to measure locations and sizes on the celestial sphere (observational astronomy).

(For completeness, the remaining four student learning outcomes are listed below, and are measured primarily through grade-related assessment):

Apply laws of spectroscopy and gravitation to remotely determine properties of satellites, planets, and stars (astronometry).
Develop and test physical models of the properties of solar system bodies (planetology).
Collect data, evaluate the data using error analysis, draw conclusions from the data.
Explain the information in a laboratory report.

Other than the positive shift for question 1, these results are comparable to those from Fall Semester 2009.

Previous posts:

20100608

Education research: ALLS post-instruction opinion results (Cuesta College, Spring Semester 2010)

Cuesta College
Astronomy Laboratory Learning Survey (ALLS) 
Post-instruction opinion results
Astronomy 210L Spring Semester 2010 sections 30678, 30679, 30680, 30682

16. Astronomy lab was (or would have been) helpful for learning in lecture.
1. Strongly disagree      3 : ***
2. Disagree               3 : ***
3. Neutral                8 : ********
4. Agree                 36 : ************************************  [3.9 +/- 1.0]
5. Strongly agree        17 : ************

17. I understand more about astronomy concepts because of what I learned in lab.
1. Strongly disagree      0 : 
2. Disagree               1 : *
3. Neutral                6 : ******
4. Agree                 42 : ******************************************  [4.1 +/- 0.6]
5. Strongly agree        18 : ******************

18. Astronomy lab was an enjoyable experience.
1. Strongly disagree      0 : 
2. Disagree               3 : ***
3. Neutral                3 : ***
4. Agree                 32 : ********************************  [4.3 +/- 0.8]
5. Strongly agree        29 : *****************************

19. Math used in astronomy lab was difficult.
1. Strongly disagree      5 : *****
2. Disagree              19 : *******************
3. Neutral               22 : **********************  [2.9 +/- 1.0]
4. Agree                 17 : *****************
5. Strongly agree         4 : ****

20. It was hard to understand concepts in astronomy lab.
1. Strongly disagree      5 : *****
2. Disagree              24 : ************************
3. Neutral               27 : ***************************  [2.7 +/- 0.9]
4. Agree                  8 : ********
5. Strongly agree         3 : ***

21. This course helped me see how astronomy is related to other sciences such as 
geology, physics, and chemistry.
1. Strongly disagree      0 : 
2. Disagree               3 : ***
3. Neutral                8 : ********
4. Agree                 45 : *********************************************  [4.0 +/- 0.7]
5. Strongly agree        11 : ***********

22. I asked a lot of questions in astronomy lab.
1. Strongly disagree      4 : ****
2. Disagree              15 : ***************
3. Neutral               28 : ****************************  [3.1 +/- 1.0]
4. Agree                 13 : *************
5. Strongly agree         7 : *******

23. I generally understood what was needed to be done in astronomy lab.
1. Strongly disagree      0 : 
2. Disagree               3 : ***
3. Neutral                6 : ******
4. Agree                 48 : ************************************************  [4.0 +/- 0.7]
5. Strongly agree        10 : **********

24. My work in astronomy lab was graded fairly.
1. Strongly disagree      0 : 
2. Disagree               1 : *
3. Neutral                1 : *
4. Agree                 34 : **********************************  [4.4 +/- 0.6]
5. Strongly agree        31 : *******************************

25. I did a lot of explaining to other students in astronomy lab.
1. Strongly disagree      2 : **
2. Disagree               5 : *****
3. Neutral               28 : ****************************  [3.4 +/- 0.9]
4. Agree                 27 : ***************************
5. Strongly agree         5 : *****

26. I was generally confused about what was going on in astronomy lab.
1. Strongly disagree      5 : *****
2. Disagree              42 : ******************************************  [2.4 +/- 0.8]
3. Neutral               12 : ************
4. Agree                  7 : *******
5. Strongly agree         1 : *

27. I would recommend astronomy lab to other students.
1. Strongly disagree      0 : 
2. Disagree               3 : ***
3. Neutral                3 : ***
4. Agree                 32 : ********************************  [4.3 +/- 0.8]
5. Strongly agree        29 : *****************************

28. Astronomy lab should only be taken in the same semester as astronomy lecture.
1. Strongly disagree      1 : *
2. Disagree              14 : **************
3. Neutral               17 : *****************
4. Agree                 19 : *******************  [3.5 +/- 1.1]
5. Strongly agree        16 : ****************

29. Astronomy lab should only be taken after completing the entire semester of 
astronomy lecture.
1. Strongly disagree     16 : ****************
2. Disagree              22 : **********************  [2.4 +/- 1.1]
3. Neutral               20 : ********************
4. Agree                  7 : *******
5. Strongly agree         2 : **

30. This course helped me feel more comfortable with the idea that many values in 
science are uncertain to some degree.
1. Strongly disagree      0 : 
2. Disagree               1 : *
3. Neutral               13 : *************
4. Agree                 32 : ********************************  [4.1 +/- 0.8]
5. Strongly agree        21 : *********************

Education research: ALLS demographic results (Cuesta College, Spring 2010)

Cuesta College
Astronomy Laboratory Learning Survey (ALLS) 
Demographic pre-instruction question results
Astronomy 210L Spring 2010 sections 30678, 30679, 30680, 30682
(N = 67, matched-pairs only)

16. What is your gender? 
(A) Female.  [34]
(B) Male.    [33]

17. Have you previously taken an astronomy lecture class? 
(A) Yes.     [24]
(B) No.      [43]

18. Are you currently enrolled in an astronomy lecture class? 
(A) Yes.     [47]
(B) No.      [20]

19. How many college science courses have you completed prior 
to taking this course? 
(A) None.    [30]
(B) 1.       [24]
(C) 2.       [ 8]
(D) 3.       [ 3]
(E) 4+.      [ 2]

20. What is your college major (or current area(s) of interest 
if undecided)?  Choose as many areas of interest that apply.  
(A) Business.                                  [11]
(B) Education.                                 [11]
(C) Humanities, Social Sciences, or the Arts.  [20]
(D) Science, Engineering, or Architecture.     [10]
(E) Other.                                     [23]

21. Which of these college math classes have you completed 
prior to taking this course?  Choose as many classes that apply.  
(A) Algebra.       [51]
(B) Trigonometry.  [12]
(C) Geometry.      [19]
(D) Pre-calculus.  [21]
(E) Calculus.      [11]
(F) Statistics.    [16]

Physics final exam problem: initial activity of radioactive sample

Physics 205B Final Exam, spring semester 2010
Cuesta College, San Luis Obispo, CA

Cf. Giambattista/Richardson/Richardson, Physics, 2/e, Problem 29.34

A commercially available sample from a medical supply company contains the isotope phosphorus-32, which undergoes β– decay with a half-life of 14.3 days. As listed on the company's website[*], new samples are prepared every Thursday. When a sample arrives on Monday morning (four days later), a Physics 205B student finds that it has an activity of 1.52×10⁷ decays/s. Determine the initial activity of this sample when it was first prepared. Show your work and explain your reasoning.

[*] las.perkinelmer.com/Catalog/ProductInfoPage.htm?ProductID=NEG502H500UC.

Solution and grading rubric:

p:
Correct. Sets up exponential or half-life exponent decay formula to solve for R₀, given R, t, and T_1/2).
r:
Nearly correct, but includes minor math errors.
t:
Nearly correct, but approach has conceptual errors, and/or major/compounded math errors.
v:
Implementation of right ideas, but in an inconsistent, incomplete, or unorganized manner.
x:
Implementation of ideas, but credit given for effort rather than merit.
y:
Irrelevant discussion/effectively blank.
z:
Blank.

Grading distribution:
Section 31988
p: 3 students
r: 6 students
t: 0 students
v: 3 students
x: 0 students
y: 0 students
z: 0 students

A sample "p" response (from student 1448) using the half-life decay formula:

A sample "p" response (from student 4747) using the exponential decay formula:

A sample "v" response (from student 7676):

20100604

Physics final exam problem: anti-glare thin film

Physics 205B Final Exam, Spring Semester 2010
Cuesta College, San Luis Obispo, CA

Cf. Giambattista/Richardson/Richardson, Physics, 2/e, Problems 25.19, 25.21

[20 points.] Glass (n = 1.52) is coated with a thin film of magnesium fluoride (n = 1.38) of thickness 125 nm. Which visible (400-700 nm) wavelength(s) in air reflects with destructive interference? Show your work and explain your reasoning.

Solution and grading rubric:

p = 20/20:
Correct. Recognizes (a) reflection off of top of MgF film causes 180 degree phase shift, as well as the reflection off of bottom of MgF film, such that the two reflected rays are in-of-phase with each other; (b) the path difference is 2*t = 125 nm; (c) for destructive interference of two in-of-phase reflected rays, delta(l) = (m + 1/2)*lambda = odd*lambda/2, where lambda is the wavelength in MgF; (d) wavelength in MgF is related to the wavelength in air by lambda = lambda_0/n_MgF, such that lambda_0 = 4*n*t/odd = 690 nm, 230 nm, ..., of which only 690 nm is in the visible light range.
r = 16/20:
Nearly correct, but includes minor math errors. Omission of one or two of concepts (a)-(d) outlined above.
t = 12/20:
Nearly correct, but approach has conceptual errors, and/or major/compounded math errors. Demonstrates some understanding of at least one of concepts (a)-(d) outlined above.
v = 8/20:
Implementation of right ideas, but in an inconsistent, incomplete, or unorganized manner.
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 31988
p: 3 students
r: 2 students
t: 2 students
v: 5 students
x: 0 students
y: 0 students
z: 0 students

A sample "p" response (from student 1987):

A sample "r" response (from student 6686), solving for the wavelength in MgF, but not relating this to the wavelength value it would have in air:

20100603

Physics final exam question: magnetic force of wire on moving charge

Physics 205B Final Exam, spring semester 2010
Cuesta College, San Luis Obispo, CA

Cf. Giambattista/Richardson/Richardson, Physics, 2/e, Problems 19.65, 19.66

A positive charge q moves upwards in the presence of a current-carrying straight wire coming out of the plane of this page. Determine the direction of the wire's magnetic field at the location of the charge, and the resulting magnetic force on the charge. Explain your reasoning using the properties of magnetic fields and forces.

Solution and grading rubric:

p:
Correct. Applies RHR2 to the wire (thumb out of page, fingers curling counterclockwise in the plane of the page) to find that B field is to the right in the plane of the page at the location of the positive charge. Then applies RHR1 to the charge (thumb up along plane of the page, index finger to the right in the plane of the page, middle finger into the page) to find that the force on the charge is into the page.
r:
As (p), but argument indirectly, weakly, or only by definition supports the statement to be proven, or has minor inconsistencies or loopholes. Has at least only one RHR completely correct.
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 31988
p: 3 students
r: 5 students
t: 4 students
v: 0 students
x: 0 students
y: 0 students
z: 0 students

A sample "p" response (from student 1987):

20100602

Physics final exam question: virtual image from converging lens

Physics 205B Final Exam, Spring Semester 2010
Cuesta College, San Luis Obispo, CA

Cf. Giambattista/Richardson/Richardson, Physics, 2/e, Multiple-Choice Question 23.7

[10 points.] An object is placed to the left of a converging lens, producing a virtual image. Determine whether this image is upright or inverted, and whether this image is enlarged or diminished. Explain your answer using equations and/or diagrams.

Solution and grading rubric:

p = 10/10:
Correct. Explains how a converging lens will always create an upright, enlarged virtual image of an object placed to the left it using equations and/or ray tracing diagrams.
r = 8/10:
As (p), but argument indirectly, weakly, or only by definition supports the statement to be proven, or has minor inconsistencies or loopholes. Discussion based on recollection of facts, but with no explicit equations or diagrams.
t = 6/10:
Nearly correct, but argument has conceptual errors, or is incomplete. Discussion of a real image using equations and/or ray tracing diagrams.
v = 4/10:
Limited relevant discussion of supporting evidence of at least some merit, but in an inconsistent or unclear manner.
x = 2/10:
Implementation/application of ideas, but credit given for effort rather than merit.
y = 1/10:
Irrelevant discussion/effectively blank.
z = 0/10:
Blank.

Grading distribution:
Section 31988
p: 4 students
r: 2 students
t: 3 students
v: 3 students
x: 0 students
y: 0 students
z: 0 students

A sample "p" response (from student 1930):

20100601

Online reading assignment question: helpful/unhelpful Midterm 2 astronomy study tips

Astronomy 210, Spring Semester 2010
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 that you did studying for this midterm that was different than the last midterm, and if it was helpful (or not). Selected comments may be discussed in class. (Graded for completion.)

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

"i went over the online possible questions and it helped a little more but not enough for me"

"i dont get what this question is asking"

"i felt that i studied more for midterm 2 then 1 but did worse on midterm 2 for some reason."

"Taking different practice open-book tests with my friends over rite aid ice cream and then when finished, each of us teaching each other what answers we picked and why..."

"QUIZZES helped a ton on multi choice; Reviewing the old midterm essay questions allowed me to focus of the general topics i should review."

"looked at flashcard questions"

"I visited you in your office hour and you were clear and helpful. much appreciated p dawg"

"Going over old quizzes more thoroughly."

"Used flash card questions to help me. Before I never used flash cards."

"Something different that i did for this midterm was that i didn't study at all."

"Studying the quiz objectives is key"

"I looked at the old midterms and they were VERY helpful"

"I printed out past midterms and studied them, but it was hard because I didn't know if my answers were right. Maybe posting midterms with the correct answers would be a lot more helpful"

"I did less studying and more cramming just before the exam (which was shown with a lower grade)."

"Study group on the weekend and the day before the exam."

"I did not study and it did not pay off!"

"I actually studied."

"I think I just spent more time on preparation for this midterm. I went over every practice quiz and had my boyfriend quiz me."

"On the essay questions if I was unable to articulate a good answer I went back and reread that section of the book. I also watched Nova on PBS and there was another really good documentary called 'Into the Universe,' which was on the discovery channel. The documentaries discussed in detail the expansion of our universe and Edwin Hubble's observations."

"Did everything pretty much the same as last time."

"i used flashcards and used the review questions online"

"milky ways i found them interesting"

"I used the study guide suggestions you put on your website and put all the material together in the study guide. Including In-class activities. I didn't do that for midterm 1, but wish I had. The short answer questions were much easier to answer for midterm 2."

"i studied the flashcard questions and the quizzes"

"not much different, doing the older midterms is a legit way to stay up grade wise"

"Just read over the book and in class notes."

"I focused a lot more on studying old quizzes this time. I think that really helped me on this midterm."

"I studied more of the old quizzes which helped."

"i read less, and it was not very helpful"

"Talked to other students about what they studied or what was hard for them and had them walk me through it and vice versa"

"i had 5 mid terms last week, so i was unable to dedicate as much study time as i would have liked to, i just had to ration my study time to maximize my scores on all of my tests, i think this had a negative effect on my grade by about 5% or so"

"i used flashcards and used the review questions online"

"I used study guide filled with all the info needed to study that was posted on your website. My girlfriend and I went over every main subject and laid out the basic concepts, then went back through and filled in the detail."

"dunno."

"I went back and study'd mid-terms 1 questions and all flashacard questions and only found there to be only 1 or 2 on the test."

"i study the pass midterm and were helpful"

"i read over old midterms that game me a better idea on what would be on the test"

"For this midterm I spent a large part of a day just rereading all the chapters and going over them slowly. I think it was extremely helpful because it forced me to study everything not just certain specifics."

"old quizes and looking over in class activivties"

"studied more and with a study group."

"Went over the flashcard questions and old tests posted on the website. And focused studying on the hints you gave us in class for the essays. Thanks P-Dog!"

"i had a general idea of what the questions would be like because of prior quizzes and the last midterm, so it was easier to eliminate the questions that i knew weren't right and zero in on the right one quickly."

"i did not look at the flashcard questions carefully and i should have"

"Instead of just depending on the flashcard questions and the archived quizzes to help me study, I carefully studied my notes that I took in class and read the summaries at the end of each chapter that was relevant to this midterm. This helped a lot because reading the book allowed me to refresh on past material that we covered before, and i was able to cement it into my head by looking through my notes taken during lecture."

"i tried to read almost the whole book a week before the test. not a good strategy on my part"

"I just studied exactly what you told us too and it worked out well for me."

"i reviewed my in class notes each day for about 5 days before the midterm, was helpful"

"i had time to study this time last time my grandfather passed away."

"i did the practice midterm from the previous semester and i believe it helped me be more prepared for what to expect
flash cards, and it helped"

"not studying doesnt help at all"

"I emphasized more on the short answer problems, not the multiple choice."

"I went over everything that was recommended by you to study which I didn't do on the first midterm.... but I probably do as good this time around!"

"doing the practice test. it helped a little"

"Definitely didn't study as much. Which is quite evident when looking at the grade I got on this guy.
I began studying much later, but I achieved a higher score."

"i went through the old activities and quizzes"

"i studied for 2 minutes longer"

"i didn't study for this one either, it seemed to work out ok again."

"i study all the class activities and flashcard questions."

"i looked over some of the short answer question from your blog which helped."

"i went to my friends house to study, but some how we studied the wrong material which led to an epic failure!"

"I reviewed old quizzes and read the parts of the chapters for the essay questions thoroughly and it made a huge difference. I felt very much prepared for this midterm."

"i retook all of the quizes and activities from class"

"nothing was different."

"i looked at the answers for the 4-6 quizzes"

"I read the back of each chapter a couple times to get the highlighted info from each chapter. It was helpful.
lol"

"i did the same thing and it was helpful d('_')b"

"the old quizes help a ton for the multiple choice but i was stumped on the onse you didnt use from the old quizes. and printing off the old short answer questions from previous semester can be helpful if you lucky enough for them to show up again haha... but studying the old quizes and in class activities you told us to help the most haha how ironic lol."

"I found myself studying the few in class activity sheets which didn't help. I studied the things that weren't on the test and what was I didn't prepare for. I have a great admiration for those who do understand this because I'm lost."

"I had more time to study for midterm 2 due to the lack of work from other classes."

"I did not spend nearly as much time studying for this midterm and my grade reflected that as far as the multiple choice went. Though my essays were all full credit"

"i actually studied :)"

"I went back and actually completed all the activities that applied to the Midterm and I mastered the material. Muahahahahaha.
I studied more of the essay questions online this time around, but it did not seem to help me very much"

"Assumed that practice midterms were going to help, but they didn't cover what was in the test."

"this time i looked over old midterms from your other semesters. i think it was more helpful for me to look over all my old quizzes though! the questions are almost identical.."

"i looked over all the flashcard question and looked for the answers in the book so it would force me to read the whole section."

"i studied the old quizes more in depth"

"I went over notes and old flash card questions!"

"Well i saved my old quizzes, went online and got the right answers for the ones i had missed and went over them. I also went to see the old short answers posed online and i went over the in class activities that we"

"this midterm i briefly reviewed the the previous midterms that where posted and it gave an idea of what might be asked
i went back in the book and reviewed previous sections"

"I looked at the in class assignments that were related to the short answer questions. it let me be more sure that i knew my stuff for those 60 pts"

"p dawwwgs blog!!"

"The only thing that I did differently in studying for this midterm was getting a large Chi Tea Latte with a pump of expresso in it. I believe this helped me in my studying the night before. Truthfully though, reviewing my lecture notes after every class period helped in my undrestanding of the concepts. The study guide was also extremely helpful. It pointed me in the right direction as to what I should specifically pay close attention tp. From this, I knew to study my old quizzes, flash card questions, in-class activities, and power point discussions. I also did not wait until the last minute to study for the exam."

"I printed all of the flashcard questions for each chapter which I though would be helpful but I think my grade reflected otherwise."