Physics 205A Quiz 4, spring semester 2009
Cuesta College, San Luis Obispo, CA
Cf. Giambattista/Richardson/Richardson, Physics, 2/e, Problems 7.7, 7.49
A 0.55 kg projectile heads towards a wall with a speed of 12.0 m/s, and after colliding, rebounds in the reverse direction along the same line with a speed of 5.0 m/s. Neglect friction and drag. The magnitude of the impulse exerted on the projectile is:
(A) 2.8 N·s.
(B) 3.9 N·s.
(C) 6.6 N·s.
(D) 9.4 N·s.
Correct answer (highlight to unhide): (D)
The impulse exerted on the projectile is given by:
J = ∆p,
J = m·(vf – v0) = (0.55 kg)·((–5.0 m/s) – (+12 m/s)) = –9.35 kg·m/s,
or to two significant figures, the magnitude of the impulse exerted on the projectile is 9.4 N·s.
Note that since the initial velocity v0 = +12 m/s is taken to be in the positive direction, then the final velocity that rebounds in the "reverse direction" must be negative: vf = –5.0 m/s.
(Response (A) is the magnitude of the final momentum; response (B) is the difference in the magnitudes of the final and initial momenta; while response (C) is the magnitude of the initial momentum.)
Student responses
Sections 30880, 30881
(A) : 3 students
(B) : 13 students
(C) : 14 students
(D) : 12 students
Success level: 27%
Discrimination index (Aubrecht & Aubrecht, 1983): 0.60
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.
20090330
20090329
Physics quiz question: Space Shuttle bat
Physics 205A Quiz 4, Spring Semester 2009
Cuesta College, San Luis Obispo, CA
Cf. Giambattista/Richardson/Richardson, Physics, 2/e, Problem 6.22
[3.0 points.] An injured fruit bat (mass 0.60 kg) that latched onto the external fuel tank of the NASA Space Shuttle was presumed to have been carried along during a recent liftoff[1]. How much energy was expended by having to lift the bat from rest to a speed of 7.8 km/s (when the fuel tank is separated[2])?
(A) 2.3e+03 J.
(B) 4.7e+03 J.
(C) 1.8e+07 J.
(D) 3.7e+07 J.
Correct answer: (C)
The energy expended (work done) is given by:
W = delta(K_tr) = (1/2)*m*(v_f^2 - v_i^2),
where v_i = 0. Response (A) is (1/2)*m*v_f; response (B) is m*v_f (the final momentum of the bat); while response (C) is m*v_f^2.
Student responses
Sections 30880, 30881
(A) : 10 students
(B) : 7 students
(C) : 26 students
(D) : 0 students
Footnotes:
[1] "NASA—Bat Hung onto Shuttle During Liftoff," www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts119/launchbat.html
[2] "17,440 mph," spaceflight.nasa.gov/shuttle/reference/basics/index.html
"Difficulty level": 60%
Discrimination index (Aubrecht & Aubrecht, 1983): 0.34
Cuesta College, San Luis Obispo, CA
Cf. Giambattista/Richardson/Richardson, Physics, 2/e, Problem 6.22
[3.0 points.] An injured fruit bat (mass 0.60 kg) that latched onto the external fuel tank of the NASA Space Shuttle was presumed to have been carried along during a recent liftoff[1]. How much energy was expended by having to lift the bat from rest to a speed of 7.8 km/s (when the fuel tank is separated[2])?
(A) 2.3e+03 J.
(B) 4.7e+03 J.
(C) 1.8e+07 J.
(D) 3.7e+07 J.
Correct answer: (C)
The energy expended (work done) is given by:
W = delta(K_tr) = (1/2)*m*(v_f^2 - v_i^2),
where v_i = 0. Response (A) is (1/2)*m*v_f; response (B) is m*v_f (the final momentum of the bat); while response (C) is m*v_f^2.
Student responses
Sections 30880, 30881
(A) : 10 students
(B) : 7 students
(C) : 26 students
(D) : 0 students
Footnotes:
[1] "NASA—Bat Hung onto Shuttle During Liftoff," www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts119/launchbat.html
[2] "17,440 mph," spaceflight.nasa.gov/shuttle/reference/basics/index.html
"Difficulty level": 60%
Discrimination index (Aubrecht & Aubrecht, 1983): 0.34
20090328
Astronomy clicker question: they might be giants
Astronomy 210, Spring Semester 2009
Cuesta College, San Luis Obispo, CA
Students were asked the following clicker question (Classroom Performance System, einstruction.com) in the middle of their learning cycle:
A __________ main sequence star will eventually become a giant.
(A) massive.
(B) medium-mass.
(C) low-mass.
(D) (More than one of the above choices.)
(E) (None of the above choices.)
(F) (I'm lost, and don't know how to answer this.)
Section 30674 (pre-)
(A) : 5 students
(B) : 19 students
(C) : 13 students
(D) : 4 students
(E) : 3 student
(F) : 0 students
This question was asked again after displaying the tallied results with the lack of consensus, with the following results. No comments were made by the instructor, in order to see if students were going to be able to discuss and determine the correct answer among themselves.
Section 30674 (post-)
(A) : 0 students
(B) : 32 students
(C) : 10 students
(D) : 1 student
(E) : 1 student
(F) : 0 students
Correct answer: (B)
A medium-mass main sequence star will become a giant when it depletes the hydrogen in its core, and the outer layers will eventually be ejected as a planetary nebula, with a white dwarf exposed at its center.
Pre- to post- peer-interaction gains:
pre-interaction correct = 43%
post-interaction correct = 72%
Hake (normalized) gain <g> = 52%
Cuesta College, San Luis Obispo, CA
Students were asked the following clicker question (Classroom Performance System, einstruction.com) in the middle of their learning cycle:
A __________ main sequence star will eventually become a giant.
(A) massive.
(B) medium-mass.
(C) low-mass.
(D) (More than one of the above choices.)
(E) (None of the above choices.)
(F) (I'm lost, and don't know how to answer this.)
Section 30674 (pre-)
(A) : 5 students
(B) : 19 students
(C) : 13 students
(D) : 4 students
(E) : 3 student
(F) : 0 students
This question was asked again after displaying the tallied results with the lack of consensus, with the following results. No comments were made by the instructor, in order to see if students were going to be able to discuss and determine the correct answer among themselves.
Section 30674 (post-)
(A) : 0 students
(B) : 32 students
(C) : 10 students
(D) : 1 student
(E) : 1 student
(F) : 0 students
Correct answer: (B)
A medium-mass main sequence star will become a giant when it depletes the hydrogen in its core, and the outer layers will eventually be ejected as a planetary nebula, with a white dwarf exposed at its center.
Pre- to post- peer-interaction gains:
pre-interaction correct = 43%
post-interaction correct = 72%
Hake (normalized) gain <g> = 52%
20090327
Astronomy in-class activity: OBAFGKM poetry slam (SLO)
Astronomy 210, Spring Semester 2009
Cuesta College, San Luis Obispo, CA
(San Luis Obispo Campus)
Astronomy 210 In-class activity 14: OBAFGKM Poetry Slam
Students were instructed to use at least OBAFGKM, and/or part or all of the additional OBAFGKMRNSC or OBAFGKMLT extensions to individually write an original, coherent and an appropriate (nothing worse than "PG-13" rated!) mnemonic, and to give a rousing reading of their OBAFGKM mnemonic poem for the class.
Old Broads Age Fast, Get Kind Mean Like Teens
--M. A.
Our Beers Are For Getting Kinda Messy! Right Now She's Clobbered
--A. A.
Oh Brah, A Fresh Grassy Killer, Mavericks Ruins New Surfers' Careers
--C. A.
Obama Bragged About Forgetting George Bush's Keys Monday
--A. C.
Oh Boy Another Full Glimpse (of a) Killer Moon Last Thursday
--S. C.
On Beaches A lot of Fish Get Killed Mmmm.
--A. D.
Only Bad Angels Fall Gently Killing Morons Like Tom
--D. D.
Outrageous Bakeries Alter Five Golden Krumble Muffins
--J. D.
(this) Old Banana Almost Feels Good...(but) Kinda Mushy
--D. D.
Only Big Apples Find Greedy Kids' Mouths
--E. E.
Only Berries Ate From Girls Kill Men
--S. F.
Our Boys Annoy Foreign Girls, Kissing Madly
--K. F.
Only Baked Arangatangs [sic] Find Great Kitchen Munchies
--P. G.
Obama Banning Americans From Guns, Kiss My Large Testicles
--T. G.
Oh Brother Another Fat Girl Kicked Me Last Tuesday
--I. H.
Oh Brother! Again, Father's Gonna Kiss Mother. That's Nasty!
--M. H.
Oh Boy! Antelopes Fly Gyrating Kites Mirthfully
--D. H.
Outrageously Bad Acting Forms Genuine Killer Mimes
--C. H.
Only Because Another Friend Gree Kindly Moved out Last Time
--J. J.
Obama Bought Anti Fire Guarding Kitchen Utensils
--I. K.
Oreos Bought At Food-4-Less Get Kindly Murdered
--Z. K.
Only Big Animals Farm Grey Koalas Majestically
--T. K.
Only Bomb Astronomers Find Giant Killer Moons
--N. K.
Old Beezies And Fat Girls Know Me
--A. K.
Obviously, Boys Always Follow Girls Killer Muffins
--D. L.
Only Burgers And Fries Gonna Keep Me Light'n Toasty
--N. L.
Often Blondes Are Flammable Guiding Kites, Many Lightning Toasts
--K. L.
Oh Boy, Another Furious Gorilla Kicked Me
--C. L.
Only Boxes Are For Girls (that) Kidnap Men
--D. M.
Obama Better Act Fast on George W's Killer Mess
--J. M.
Oh Boy Another Fun Game of Kings, Man!
--S. M.
Obama Begged Armed Forces (to) Go Kill My Redneck Neighbor (in) South Central
--J. M.
Oh Boo! A Fat Goat Kicked Me.
--J. M.
Only Bald Angry Farmers Get Knudsen Milk
--J. P.
Obese Baby Alligators Form Gangs, Killing Many
--T. P.
Oh-Bama Ate Frozen Gorillas, Kangaroos (and) Monkeys
--M. P.
Oscar Better Always Fly Green Kites, Man
Only Bad-Ass Females Get Kisses Mucho
--D. P.
Orange Beanbags Are For German Kings Making Ridiculous Non-Scientific Claims
--J. P.
Only Bright Astronomers Find Giant Killer Martians
--F. R.
Orange Bobcats Always Fight Gigantic Killer Monkeys Riding Nigerian Sand Camels
--R. S.
Oscar Buys Apples From Good, Kind Merchants
--A. S.
Our Bikinis Aren't For Going Kayaking Monday
--C. S.
Over Break A Freak Gave Kim Mono
--E. S.
Old Bitches Are F-ing Good Knitters, Man
--E. S.
Old Bad A** Farmers Grow Killer Mangos
--A. T.
Only Big Angry Females Get Kind Men
--T. T.
Out Back After Football Games Kids Make Loud Noise Towards Rivals
--K. T.
Ouch Bro A Freaking Gorilla Kung fu'ed Me Last Thursday
--K. W.
Other Beings Arrived From Green Knarred Moons
--N. W.
One Bright Asteroid's Fire Glow Keeps Moving Rapidly Near Southern California
--S. W.
Oh Baby, All Foreign Guys Kill Me
--S. W.
Only Big Angry Ferocious Gangly Kangaroos Make Cookies
--C. Z.
Previous post: Astronomy in-class activity: OBAFGKM poetry slam instructions.
Cuesta College, San Luis Obispo, CA
(San Luis Obispo Campus)
Astronomy 210 In-class activity 14: OBAFGKM Poetry Slam
Students were instructed to use at least OBAFGKM, and/or part or all of the additional OBAFGKMRNSC or OBAFGKMLT extensions to individually write an original, coherent and an appropriate (nothing worse than "PG-13" rated!) mnemonic, and to give a rousing reading of their OBAFGKM mnemonic poem for the class.
Old Broads Age Fast, Get Kind Mean Like Teens
--M. A.
Our Beers Are For Getting Kinda Messy! Right Now She's Clobbered
--A. A.
Oh Brah, A Fresh Grassy Killer, Mavericks Ruins New Surfers' Careers
--C. A.
Obama Bragged About Forgetting George Bush's Keys Monday
--A. C.
Oh Boy Another Full Glimpse (of a) Killer Moon Last Thursday
--S. C.
On Beaches A lot of Fish Get Killed Mmmm.
--A. D.
Only Bad Angels Fall Gently Killing Morons Like Tom
--D. D.
Outrageous Bakeries Alter Five Golden Krumble Muffins
--J. D.
(this) Old Banana Almost Feels Good...(but) Kinda Mushy
--D. D.
Only Big Apples Find Greedy Kids' Mouths
--E. E.
Only Berries Ate From Girls Kill Men
--S. F.
Our Boys Annoy Foreign Girls, Kissing Madly
--K. F.
Only Baked Arangatangs [sic] Find Great Kitchen Munchies
--P. G.
Obama Banning Americans From Guns, Kiss My Large Testicles
--T. G.
Oh Brother Another Fat Girl Kicked Me Last Tuesday
--I. H.
Oh Brother! Again, Father's Gonna Kiss Mother. That's Nasty!
--M. H.
Oh Boy! Antelopes Fly Gyrating Kites Mirthfully
--D. H.
Outrageously Bad Acting Forms Genuine Killer Mimes
--C. H.
Only Because Another Friend Gree Kindly Moved out Last Time
--J. J.
Obama Bought Anti Fire Guarding Kitchen Utensils
--I. K.
Oreos Bought At Food-4-Less Get Kindly Murdered
--Z. K.
Only Big Animals Farm Grey Koalas Majestically
--T. K.
Only Bomb Astronomers Find Giant Killer Moons
--N. K.
Old Beezies And Fat Girls Know Me
--A. K.
Obviously, Boys Always Follow Girls Killer Muffins
--D. L.
Only Burgers And Fries Gonna Keep Me Light'n Toasty
--N. L.
Often Blondes Are Flammable Guiding Kites, Many Lightning Toasts
--K. L.
Oh Boy, Another Furious Gorilla Kicked Me
--C. L.
Only Boxes Are For Girls (that) Kidnap Men
--D. M.
Obama Better Act Fast on George W's Killer Mess
--J. M.
Oh Boy Another Fun Game of Kings, Man!
--S. M.
Obama Begged Armed Forces (to) Go Kill My Redneck Neighbor (in) South Central
--J. M.
Oh Boo! A Fat Goat Kicked Me.
--J. M.
Only Bald Angry Farmers Get Knudsen Milk
--J. P.
Obese Baby Alligators Form Gangs, Killing Many
--T. P.
Oh-Bama Ate Frozen Gorillas, Kangaroos (and) Monkeys
--M. P.
Oscar Better Always Fly Green Kites, Man
Only Bad-Ass Females Get Kisses Mucho
--D. P.
Orange Beanbags Are For German Kings Making Ridiculous Non-Scientific Claims
--J. P.
Only Bright Astronomers Find Giant Killer Martians
--F. R.
Orange Bobcats Always Fight Gigantic Killer Monkeys Riding Nigerian Sand Camels
--R. S.
Oscar Buys Apples From Good, Kind Merchants
--A. S.
Our Bikinis Aren't For Going Kayaking Monday
--C. S.
Over Break A Freak Gave Kim Mono
--E. S.
Old Bitches Are F-ing Good Knitters, Man
--E. S.
Old Bad A** Farmers Grow Killer Mangos
--A. T.
Only Big Angry Females Get Kind Men
--T. T.
Out Back After Football Games Kids Make Loud Noise Towards Rivals
--K. T.
Ouch Bro A Freaking Gorilla Kung fu'ed Me Last Thursday
--K. W.
Other Beings Arrived From Green Knarred Moons
--N. W.
One Bright Asteroid's Fire Glow Keeps Moving Rapidly Near Southern California
--S. W.
Oh Baby, All Foreign Guys Kill Me
--S. W.
Only Big Angry Ferocious Gangly Kangaroos Make Cookies
--C. Z.
Previous post: Astronomy in-class activity: OBAFGKM poetry slam instructions.
20090326
Physics midterm question: average speed equals average velocity magnitude?
Physics 205A Midterm 1, spring semester 2009
Cuesta College, San Luis Obispo, CA
Can the average speed and the magnitude of the average velocity be equal? If so, give an example. If not, then discuss why not. Explain your reasoning by using the properties of position, distance traveled, displacement, velocity, and speed.
Solution and grading rubric:
Sections 30880, 30881
p: 9 students
r: 4 students
t: 16 students
v: 7 students
x: 2 students
y: 0 students
z: 1 student
A sample of a "p" response (from student 0506) with an example of straight-line travel, where average speed and the magnitude of average velocity would be equal:
Another sample "p" response (from student 4974) showing examples where average speed and the magnitude of average velocity would not be equal:
A sample "t" response (from student 4469) positing that average speed would be by definition the magnitude of the average velocity vector (which would only be true for the instantaneous speed and instantaneous velocity):
Cuesta College, San Luis Obispo, CA
Can the average speed and the magnitude of the average velocity be equal? If so, give an example. If not, then discuss why not. Explain your reasoning by using the properties of position, distance traveled, displacement, velocity, and speed.
Solution and grading rubric:
- p:
Correct. Argues either case where they may be equal to each other (straight line travel with no reverse direction changes, or at rest); or argues that they cannot be equal (in general) for typically non-straight paths. - r:
As (p), but argument indirectly, weakly, or only by definition supports the statement to be proven, or has minor inconsistencies or loopholes. May confuse instantaneous with average quantities, or involve +/– directions when discussing magnitudes. - t:
Nearly correct, but argument has conceptual errors, or is incomplete. At least recognizes average speed is magnitude of average velocity, or that straight line travel is required, but may interpret "average" as adding multiple quantities and dividing by number of items. - 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.
Sections 30880, 30881
p: 9 students
r: 4 students
t: 16 students
v: 7 students
x: 2 students
y: 0 students
z: 1 student
A sample of a "p" response (from student 0506) with an example of straight-line travel, where average speed and the magnitude of average velocity would be equal:
Another sample "p" response (from student 4974) showing examples where average speed and the magnitude of average velocity would not be equal:
A sample "t" response (from student 4469) positing that average speed would be by definition the magnitude of the average velocity vector (which would only be true for the instantaneous speed and instantaneous velocity):
20090325
Physics midterm problem: downwards-aimed shotgun
Physics 205A Midterm 1, spring semester 2009
Cuesta College, San Luis Obispo, CA
Cf. Giambattista/Richardson/Richardson, Physics, 2/e, Problem 3.62(c)
A shotgun fires a large number of pellets downwards, with some pellets traveling very nearly vertically, and others spread out as much as 3.000° from the downwards vertical direction. Assume that the initial speed of these pellets is 180.0 m/s. Ignore air resistance. Find the maximum horizontal displacement that these pellets will hit the ground, as measured from the vertical. Show your work and explain your reasoning.
Solution and grading rubric:
Sections 30880, 30881
p: 11 students
r: 4 students
t: 2 students
v: 22 students
x: 6 students
y: 1 student
z: 0 students
A sample "p" response (from student 6447):
A sample "t" response (from student 6363), finding the answer in the absence of gravity:
A sample "v" response (from student 1697), purely appealing to trigonometry:
Cuesta College, San Luis Obispo, CA
Cf. Giambattista/Richardson/Richardson, Physics, 2/e, Problem 3.62(c)
A shotgun fires a large number of pellets downwards, with some pellets traveling very nearly vertically, and others spread out as much as 3.000° from the downwards vertical direction. Assume that the initial speed of these pellets is 180.0 m/s. Ignore air resistance. Find the maximum horizontal displacement that these pellets will hit the ground, as measured from the vertical. Show your work and explain your reasoning.
Solution and grading rubric:
- p:
Correct. Finds x- and y-components of initial velocity: v0x = +9.42 m/s, v0y = –179.8 m/s. May either use quadratic equation or time-eliminated kinematic equation along the y-direction to respectively find the elapsed time or the final vy when the pellet hits the ground, which can then be used to find the final horizontal position x where the pellet hits the ground. - r:
Nearly correct, but includes minor math errors. Typically solves for elapsed time correctly, but inadvertently uses v0y instead of v0x in calculating the horizontal distance traveled. - t:
Nearly correct, but approach has conceptual errors, and/or major/compounded math errors. At least attempts to solve for elapsed time before substituting into x = v0x⋅t. - v:
Implementation of right ideas, but in an inconsistent, incomplete, or unorganized manner. Still has a methodical approach based on the kinematic equations of motion, or may estimate distance from appealing to trigonometric relations between initial angle, y and/or x, which would only be true if ay = 0. - x:
Implementation of ideas, but credit given for effort rather than merit. - y:
Irrelevant discussion/effectively blank. - z:
Blank.
Sections 30880, 30881
p: 11 students
r: 4 students
t: 2 students
v: 22 students
x: 6 students
y: 1 student
z: 0 students
A sample "p" response (from student 6447):
A sample "t" response (from student 6363), finding the answer in the absence of gravity:
A sample "v" response (from student 1697), purely appealing to trigonometry:
20090324
Physics midterm problem: pushing box up ramp
Physics 205A Midterm 1, Spring Semester 2009
Cuesta College, San Luis Obispo, CA
Cf. Giambattista/Richardson/Richardson, Physics, 2/e, Comprehensive Problem 4.112
[20 points.] A Physics 205A student wants to push a 40.0 kg box up a 18.0 degree ramp. The coefficient of kinetic friction between the box and the ramp is 0.290. With what magnitude force parallel to the ramp should the student push on the box so that it moves up the ramp at constant speed?
Solution and grading rubric:
Grading distribution:
Sections 30880, 30881
p: 8 students
r: 8 students
t: 14 students
v: 14 students
x: 1 student
y: 1 student
z: 0 students
A sample "p" response (from student 1830):
A sample "r" response (from student 4444), where the x-component of weight is ignored:
Another sample "r" response (from student 2679), where the x-component of weight is included, but the normal force was set equal to the magnitude of weight, instead of its y-component:
A sample "t" response (from student 0406), including both errors described above from the previous sample "r" responses:
Cuesta College, San Luis Obispo, CA
Cf. Giambattista/Richardson/Richardson, Physics, 2/e, Comprehensive Problem 4.112
[20 points.] A Physics 205A student wants to push a 40.0 kg box up a 18.0 degree ramp. The coefficient of kinetic friction between the box and the ramp is 0.290. With what magnitude force parallel to the ramp should the student push on the box so that it moves up the ramp at constant speed?
Solution and grading rubric:
- p = 20/20:
Correct. Resolves weight into w_x and w_y components (parallel and perpendicular to ramp, respectively). Then applies Newton's first law in both x- and y-directions to find normal force of ramp on box, and applied force on box (which is equal to w_x + f_k). - r = 16/20:
Nearly correct, but includes minor math errors. Typically uses N = w = m*g instead of N = w_y = m*g*cos(theta), otherwise methodical application of Newton's first law along x-direction; or sets F_app = f_k only, neglecting w_x component, but has N = w_y correct. - t = 12/20:
Nearly correct, but approach has conceptual errors, and/or major/compounded math errors. Some attempt at resolving w into components on a substantive free-body diagram, and methodical application of Newton's first law. May have both of the two errors described in (r). - v = 8/20:
Implementation of right ideas, but in an inconsistent, incomplete, or unorganized manner. Serious attempt at free-body diagram or application of Newton's laws. - 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:
Sections 30880, 30881
p: 8 students
r: 8 students
t: 14 students
v: 14 students
x: 1 student
y: 1 student
z: 0 students
A sample "p" response (from student 1830):
A sample "r" response (from student 4444), where the x-component of weight is ignored:
Another sample "r" response (from student 2679), where the x-component of weight is included, but the normal force was set equal to the magnitude of weight, instead of its y-component:
A sample "t" response (from student 0406), including both errors described above from the previous sample "r" responses:
20090323
Astronomy quiz question: hottest star
Astronomy 210 Quiz 4, Spring Semester 2009
Cuesta College, San Luis Obispo, CA
Which star is the hottest?
(A) F5 supergiant.
(B) B0 main-sequence star.
(C) M5 main-sequence star (red dwarf).
(D) A0 white dwarf.
Section 30676
(A) : 12 students
(B) : 25 students
(C) : 2 students
(D) : 16 students
Correct answer: (B)
Using the OBAFGKM spectral type mnemonic, or reading off of an H-R diagram (provided on this quiz), the B0 main-sequence star is the hottest, followed by the A0 white dwarf, F5 supergiant, and M5 red dwarf. Apparently students chose the F5 supergiant for being the largest star, or the A0 white dwarf for being "white-hot" (when in fact the B0 main-sequence star would be a hotter white-, or even blue-hot in appearance).
"Difficulty level": 51% (including partial credit for multiple-choice)
Discrimination index (Aubrecht & Aubrecht, 1983): 0.81
Cuesta College, San Luis Obispo, CA
Which star is the hottest?
(A) F5 supergiant.
(B) B0 main-sequence star.
(C) M5 main-sequence star (red dwarf).
(D) A0 white dwarf.
Section 30676
(A) : 12 students
(B) : 25 students
(C) : 2 students
(D) : 16 students
Correct answer: (B)
Using the OBAFGKM spectral type mnemonic, or reading off of an H-R diagram (provided on this quiz), the B0 main-sequence star is the hottest, followed by the A0 white dwarf, F5 supergiant, and M5 red dwarf. Apparently students chose the F5 supergiant for being the largest star, or the A0 white dwarf for being "white-hot" (when in fact the B0 main-sequence star would be a hotter white-, or even blue-hot in appearance).
"Difficulty level": 51% (including partial credit for multiple-choice)
Discrimination index (Aubrecht & Aubrecht, 1983): 0.81
20090322
Physics clicker question: wall impulse on bounced ball
Physics 205A, Spring Semester 2009
Cuesta College, San Luis Obispo, CA
Cf. Giambattista/Richardson/Richardson, Physics, 2/e, Problem 7.7 (extended)
Students were asked the following clicker questions (Classroom Performance System, einstruction.com) in the beginning of their learning cycle:
A 5.0 kg ball is moving with a speed of 3.0 m/s in the +x direction, and then hits a wall and bounces back with the same speed in the –x direction. What is the sign of the impulse exerted by the wall on the ball?
(A) Negative.
(B) Positive.
(C) (Zero.)
(D) (I'm lost, and don't know how to answer this.)
Sections 30880, 30881
(A) : 22 students
(B) : 9 students
(C) : 8 students
(D) : 0 students
This question was asked again after displaying the tallied results with the lack of consensus, with the following results. No comments were made by the instructor, in order to see if students were going to be able to discuss and determine the correct answer among themselves.
Sections 30880, 30881
(A) : 27 students
(B) : 6 students
(C) : 5 students
(D) : 0 students
Correct answer: (A)
The impulse exerted by the wall on the ball is the force exerted on the ball multiplied by the time elapsed during wall-ball contact, which will result in a vector pointing in the negative direction. Also the impulse can be calculated from the initial-to-final change in momentum m*v_f - m*v_i = (5.0 kg)*((-3.0 m/s) - (+3/0 m/s) = -30 N*s, which also points in the negative direction.
Pre- to post- peer-interaction gains:
pre-interaction correct = 56%
post-interaction correct = 71%
Hake, or normalized gain = 34%
Cuesta College, San Luis Obispo, CA
Cf. Giambattista/Richardson/Richardson, Physics, 2/e, Problem 7.7 (extended)
Students were asked the following clicker questions (Classroom Performance System, einstruction.com) in the beginning of their learning cycle:
A 5.0 kg ball is moving with a speed of 3.0 m/s in the +x direction, and then hits a wall and bounces back with the same speed in the –x direction. What is the sign of the impulse exerted by the wall on the ball?
(A) Negative.
(B) Positive.
(C) (Zero.)
(D) (I'm lost, and don't know how to answer this.)
Sections 30880, 30881
(A) : 22 students
(B) : 9 students
(C) : 8 students
(D) : 0 students
This question was asked again after displaying the tallied results with the lack of consensus, with the following results. No comments were made by the instructor, in order to see if students were going to be able to discuss and determine the correct answer among themselves.
Sections 30880, 30881
(A) : 27 students
(B) : 6 students
(C) : 5 students
(D) : 0 students
Correct answer: (A)
The impulse exerted by the wall on the ball is the force exerted on the ball multiplied by the time elapsed during wall-ball contact, which will result in a vector pointing in the negative direction. Also the impulse can be calculated from the initial-to-final change in momentum m*v_f - m*v_i = (5.0 kg)*((-3.0 m/s) - (+3/0 m/s) = -30 N*s, which also points in the negative direction.
Pre- to post- peer-interaction gains:
pre-interaction correct = 56%
post-interaction correct = 71%
Hake, or normalized gain
20090321
Astronomy quiz question: red dwarf star vs. red giant
Astronomy 210 Quiz 4, Spring Semester 2009
Cuesta College, San Luis Obispo, CA
A red dwarf star is known to be smaller than a giant star that has the same red-hot color because it is:
(A) less luminous than the giant star.
(B) cooler than giant star.
(C) more luminous than the giant star.
(D) hotter than the giant star.
Section 30674
(A) : 28 students
(B) : 2 students
(C) : 5 students
(D) : 0 students
Correct answer: (A)
From Wien's law, the red dwarf star and the giant must have the same temperature, because they have the same color. From the Stefan-Boltzmann law, for two stars of the same temperature, the less luminous star must be smaller in size.
"Difficulty level": 78% (including partial credit for multiple-choice)
Discrimination index (Aubrecht & Aubrecht, 1983): 0.40
Cuesta College, San Luis Obispo, CA
A red dwarf star is known to be smaller than a giant star that has the same red-hot color because it is:
(A) less luminous than the giant star.
(B) cooler than giant star.
(C) more luminous than the giant star.
(D) hotter than the giant star.
Section 30674
(A) : 28 students
(B) : 2 students
(C) : 5 students
(D) : 0 students
Correct answer: (A)
From Wien's law, the red dwarf star and the giant must have the same temperature, because they have the same color. From the Stefan-Boltzmann law, for two stars of the same temperature, the less luminous star must be smaller in size.
"Difficulty level": 78% (including partial credit for multiple-choice)
Discrimination index (Aubrecht & Aubrecht, 1983): 0.40
20090320
Wordle: P-dog's blog
090315 waiferx.blogspot.com Wordle
http://www.flickr.com/photos/waiferx/3357553963/
Originally uploaded by Waifer X
Wordle.net tag cloud for this blog on March 15, 2009 (www.wordle.net/gallery/wrdl/653929/Untitled).
http://www.flickr.com/photos/waiferx/3357553963/
Originally uploaded by Waifer X
Wordle.net tag cloud for this blog on March 15, 2009 (www.wordle.net/gallery/wrdl/653929/Untitled).
20090319
Student scribble: P-dog
200903041706_189
http://www.flickr.com/photos/waiferx/3348298578/
Originally uploaded by Waifer X
Student graffiti ironically captured on a cell phone, March 4, 2009, Science Forum 2402, Cuesta College, San Luis Obispo, CA.
http://www.flickr.com/photos/waiferx/3348298578/
Originally uploaded by Waifer X
Student graffiti ironically captured on a cell phone, March 4, 2009, Science Forum 2402, Cuesta College, San Luis Obispo, CA.
20090318
Astronomy midterm question: total solar eclipse locations
Astronomy 210 Midterm 1, Spring Semester 2009
Cuesta College, San Luis Obispo, CA
[20 points.] At 10 AM, you are currently observing a total solar eclipse in San Luis Obispo, CA. Suppose you decided to call a friend who lives in Seattle, WA, which is north of San Luis Obispo, CA. Explain what kind of eclipse (if any) your friend would be able to see in Seattle, WA at the same time, or why not, using a diagram of Earth, the moon, and shadow zones. Assume that the skies are clear in both San Luis Obispo, CA and Seattle, WA.
(Adapted from a test bank question from Karl F. Kuhn, Theo Koupelis, In Quest of the Universe.)
Solution and grading rubric:
Section 30676
p: 16 students
r: 20 students
t: 12 students
v: 16 students
x: 0 students
y: 0 students
z: 0 students
A sample "p" response, with a "not to scale" disclaimer (from student 0321):
Another sample "p" response, again with a "not to scale" disclaimer (from student 1987):
A "p" response that is drawn "perfectly" to scale (from student 2525):
A "p" response (from student 1192, impressed with a diagram which inexplicably includes a one-eyed Sun):
A sample "t" response, lacking a diagram (from student 1713):
A sample "v" response (from student 8008), claiming that the Seattle, WA observer will simultaneously be seeing a total solar eclipse:
Another sample "v" response (from student 3553), with a simultaneous lunar eclipse for the Seattle, WA observer:
A sample "v" response (from student 4143) with a partial solar eclipse for Seattle, WA, but with no diagram or further explanation other than schadenfreude:
Cuesta College, San Luis Obispo, CA
[20 points.] At 10 AM, you are currently observing a total solar eclipse in San Luis Obispo, CA. Suppose you decided to call a friend who lives in Seattle, WA, which is north of San Luis Obispo, CA. Explain what kind of eclipse (if any) your friend would be able to see in Seattle, WA at the same time, or why not, using a diagram of Earth, the moon, and shadow zones. Assume that the skies are clear in both San Luis Obispo, CA and Seattle, WA.
(Adapted from a test bank question from Karl F. Kuhn, Theo Koupelis, In Quest of the Universe.)
Solution and grading rubric:
- p = 20/20:
Correct. Draws a diagram clearly showing the umbral and penumbral shadow zones (in space and/or projected onto Earth's surface), showing San Luis Obispo, CA within a very small umbral "dot," and Seattle, WA either in or outside of the penumbra, with corresponding correct discussion of observing a partial solar eclipse, or no eclipse at all simultaneously. May have a technical error with showing an annular eclipse rather than a total eclipse, with San Luis Obispo, CA in the "negative shadow" (the antumbra) past the apex of the Moon's umbra. - r = 16/20:
Nearly correct (explanation weak, unclear or only nearly complete); includes extraneous/tangential information; or has minor errors. Typically
missing penumbra. - t = 12/20:
Contains right ideas, but discussion is unclear/incomplete or contains major errors. Discusses a partial solar eclipse in Seattle, WA, with little or no diagram, but with plausible arguments regarding scale of Sun, the Moon, and shadow zones. - v = 8/20:
Limited relevant discussion of supporting evidence of at least some merit, but in an inconsistent or unclear manner. Typically says Seattle, WA observer will experience a total solar eclipse simultaneously with or subsequent to the San Luis Obispo, CA observer, or incomplete diagram of some merit. - x = 4/20:
Implementation/application of ideas, but credit given for effort rather than merit. Involving unrelated factors. - y = 2/20:
Irrelevant discussion/effectively blank. - z = 0/20:
Blank.
Section 30676
p: 16 students
r: 20 students
t: 12 students
v: 16 students
x: 0 students
y: 0 students
z: 0 students
A sample "p" response, with a "not to scale" disclaimer (from student 0321):
Another sample "p" response, again with a "not to scale" disclaimer (from student 1987):
A "p" response that is drawn "perfectly" to scale (from student 2525):
A "p" response (from student 1192, impressed with a diagram which inexplicably includes a one-eyed Sun):
A sample "t" response, lacking a diagram (from student 1713):
A sample "v" response (from student 8008), claiming that the Seattle, WA observer will simultaneously be seeing a total solar eclipse:
Another sample "v" response (from student 3553), with a simultaneous lunar eclipse for the Seattle, WA observer:
A sample "v" response (from student 4143) with a partial solar eclipse for Seattle, WA, but with no diagram or further explanation other than schadenfreude:
20090317
Astronomy midterm question: future lunar phases
Astronomy 210 Midterm 1, Spring Semester 2009
Cuesta College, San Luis Obispo, CA
The Moon is in its waxing gibbous phase tonight. How many of the four phases shown above will the Moon pass through in the next two weeks? (Do not circle the phase pictures; clearly circle an (A)-(E) response below.)
(A) (None of the above phases.)
(B) One.
(C) Two.
(D) Three.
(E) Four.
Section 30676
(A) : 8 students
(B) : 25 students
(C) : 19 students
(D) : 9 students
(E) : 3 students
Correct answer: (B)
Starting from waxing gibbous, the phases the Moon will go through in the two weeks would be full, waning gibbous, third quarter, and waning crescent (which is "halfway" around the Moon's orbit, approximately two weeks later). Thus out of the above choices (new, first quarter, waxing crescent, waning gibbous), the Moon would only go through one (waning gibbous).
"Difficulty level": 44% (including partial credit for multiple-choice)
Discrimination index (Aubrecht & Aubrecht, 1983): 0.42
Cuesta College, San Luis Obispo, CA
The Moon is in its waxing gibbous phase tonight. How many of the four phases shown above will the Moon pass through in the next two weeks? (Do not circle the phase pictures; clearly circle an (A)-(E) response below.)
(A) (None of the above phases.)
(B) One.
(C) Two.
(D) Three.
(E) Four.
Section 30676
(A) : 8 students
(B) : 25 students
(C) : 19 students
(D) : 9 students
(E) : 3 students
Correct answer: (B)
Starting from waxing gibbous, the phases the Moon will go through in the two weeks would be full, waning gibbous, third quarter, and waning crescent (which is "halfway" around the Moon's orbit, approximately two weeks later). Thus out of the above choices (new, first quarter, waxing crescent, waning gibbous), the Moon would only go through one (waning gibbous).
"Difficulty level": 44% (including partial credit for multiple-choice)
Discrimination index (Aubrecht & Aubrecht, 1983): 0.42
20090316
Astronomy in-class activity: OBAFGKM poetry slam (NCC)
Astronomy 210, Spring Semester 2009
Cuesta College, San Luis Obispo, CA
(North County Campus)
Astronomy 210 In-class activity 14: OBAFGKM Poetry Slam
Students were instructed to use at least OBAFGKM, and/or part or all of the additional OBAFGKMRNSC or OBAFGKMLT extensions to individually write an original, coherent and an appropriate (nothing worse than "PG-13" rated!) mnemonic, and to give a rousing reading of their OBAFGKM mnemonic poem for the class.
Only Bad Ants Find Good Kyanite Minerals
--J. A.
Oh Brother Astronomy Freakin' Gets Kids Mad
--D. B.
Obesity Brings Anguish For Genghis Khan's Mule
--E. B.
Only B____ Always Forgets Gregarious Kooky Mr. Len [Assignments]
--B. B.
Orange Bats Are Fighting Giant Killer Moles
--B. B.
Offer Beer After Breaky Girls Know Me
--F. C.
Only Bringing A Few Good Kine Mexicans Over
--A. E.
Outrigger Boys Always Find Good Kine Music
--P. E.
One Best Absolute Favorite Game Kids Mind
--R. H.
Oh Boy A Fun Game Kills Me
--I. H.
Obviously, Booze And Friendly Girls Keep Men Loving Taverns
--J. H.
Orangutangs Built Ancient Farms [to] Grow Killer Meatballs
--E. H.
Oh Brother Another Furry Gerbil Keeps Masterfully Running Nonsense Semi-Circles
--C. J.
Outrageously Big Animals Fight Gorilla Killing Machines
--J. M.
Occasionally, Babbling About Foreign Goats Kinda Makes Life Tedious
--K. N.
Our Boys Ask For Great Killer Motorcycles
--W. O.
Obama Barack African Fake Gonna Kill Many
--C. P.
Oh Baby! Another Fricken GREAT Kylie Monogue Single!
--A. R.
Oranges, Bananas, Apples, Figs, Grapes, Kiwi, and Mangos [Are All Yummy Fruits]
--C. R.
Orion Boasted About Favored Gemini; Kin Mythical Look-alikes, Temperaments Reversed
--R. R.
Orange Baboons Are Fighting Gorilla-Kicking Monkeys [and] Losing Terribly
Open Boxes Are For Gathering Kite Material
--L. R.
Often Building And Fixing Galleon Keels, Magellan Finally Left To Explore
--J. S.
Oh Blasphemy! Another Failing Grade Kills Me!
--A. S.
Orion Bugged Aries For Googling Kind Midas
--Y. S.
Only Buttheads Ask For Goofy Kids Movies
--K. T.
Organic Bananas Are For Global-warming Knowing Monkeys
--C. W.
Only Baked Astronauts Fear Gnomes Krumping Makes Ludicrous Turbulence
--C. W.
Only Brown Alligators Find Giant Kittens Mouth-watering
--S. W.
Previous post: Astronomy in-class activity: OBAFGKM poetry slam instructions.
Cuesta College, San Luis Obispo, CA
(North County Campus)
Astronomy 210 In-class activity 14: OBAFGKM Poetry Slam
Students were instructed to use at least OBAFGKM, and/or part or all of the additional OBAFGKMRNSC or OBAFGKMLT extensions to individually write an original, coherent and an appropriate (nothing worse than "PG-13" rated!) mnemonic, and to give a rousing reading of their OBAFGKM mnemonic poem for the class.
Only Bad Ants Find Good Kyanite Minerals
--J. A.
Oh Brother Astronomy Freakin' Gets Kids Mad
--D. B.
Obesity Brings Anguish For Genghis Khan's Mule
--E. B.
Only B____ Always Forgets Gregarious Kooky Mr. Len [Assignments]
--B. B.
Orange Bats Are Fighting Giant Killer Moles
--B. B.
Offer Beer After Breaky Girls Know Me
--F. C.
Only Bringing A Few Good Kine Mexicans Over
--A. E.
Outrigger Boys Always Find Good Kine Music
--P. E.
One Best Absolute Favorite Game Kids Mind
--R. H.
Oh Boy A Fun Game Kills Me
--I. H.
Obviously, Booze And Friendly Girls Keep Men Loving Taverns
--J. H.
Orangutangs Built Ancient Farms [to] Grow Killer Meatballs
--E. H.
Oh Brother Another Furry Gerbil Keeps Masterfully Running Nonsense Semi-Circles
--C. J.
Outrageously Big Animals Fight Gorilla Killing Machines
--J. M.
Occasionally, Babbling About Foreign Goats Kinda Makes Life Tedious
--K. N.
Our Boys Ask For Great Killer Motorcycles
--W. O.
Obama Barack African Fake Gonna Kill Many
--C. P.
Oh Baby! Another Fricken GREAT Kylie Monogue Single!
--A. R.
Oranges, Bananas, Apples, Figs, Grapes, Kiwi, and Mangos [Are All Yummy Fruits]
--C. R.
Orion Boasted About Favored Gemini; Kin Mythical Look-alikes, Temperaments Reversed
--R. R.
Orange Baboons Are Fighting Gorilla-Kicking Monkeys [and] Losing Terribly
Open Boxes Are For Gathering Kite Material
--L. R.
Often Building And Fixing Galleon Keels, Magellan Finally Left To Explore
--J. S.
Oh Blasphemy! Another Failing Grade Kills Me!
--A. S.
Orion Bugged Aries For Googling Kind Midas
--Y. S.
Only Buttheads Ask For Goofy Kids Movies
--K. T.
Organic Bananas Are For Global-warming Knowing Monkeys
--C. W.
Only Baked Astronauts Fear Gnomes Krumping Makes Ludicrous Turbulence
--C. W.
Only Brown Alligators Find Giant Kittens Mouth-watering
--S. W.
Previous post: Astronomy in-class activity: OBAFGKM poetry slam instructions.
20090315
Astronomy midterm question: total lunar eclipse versus total solar eclipse duration
Astronomy 210 Midterm 1, Spring Semester 2009
Cuesta College, San Luis Obispo, CA
[20 points.] Why does an observer see a total lunar eclipse lasting much longer than a total solar eclipse? Defend your answer using a diagram showing the positions of an observer, Earth, the moon, and shadow zones.
Solution and grading rubric:
Section 30674
p: 8 students
r: 6 students
t: 7 students
v: 17 students
x: 2 students
y: 0 students
z: 0 students
A sample "p" response (from student 1959):
A sample "t" response (from student 1889):
A sample "v" response, with diagram only (from student 1213):
Cuesta College, San Luis Obispo, CA
[20 points.] Why does an observer see a total lunar eclipse lasting much longer than a total solar eclipse? Defend your answer using a diagram showing the positions of an observer, Earth, the moon, and shadow zones.
Solution and grading rubric:
- p = 20/20:
Correct. The size of the umbra created by the Moon makes total solar eclipses last only a few minutes, as the umbral spot passes quickly over an observer's position. The size of the umbra created by the Earth makes total lunar eclipses last a few hours, as it will take that long for the Moon to pass through this shadow zone of the Earth. Has a correct explanation, and clear, correct diagrams of a total solar eclipse and a total lunar eclipse demonstrating the effect of umbra sizes. - r = 16/20:
Nearly correct (explanation weak, unclear or only nearly complete); includes extraneous/tangential information; or has minor errors. Typically incomplete or inconsistent diagrams. - t = 12/20:
Contains right ideas, but discussion is unclear/incomplete or contains major errors. Diagrams problematic, but at least recognizes importance of sizes of umbrae. - v = 8/20:
Limited relevant discussion of supporting evidence of at least some merit, but in an inconsistent or unclear manner. Plausible arguments involving varying orbital speeds, precession of nodes, varying orbital distances, with some attempt at diagrams. Or substantively correct diagrams only. - x = 4/20:
Implementation/application of ideas, but credit given for effort rather than merit. Involving unrelated factors. - y = 2/20:
Irrelevant discussion/effectively blank. - z = 0/20:
Blank.
Section 30674
p: 8 students
r: 6 students
t: 7 students
v: 17 students
x: 2 students
y: 0 students
z: 0 students
A sample "p" response (from student 1959):
A sample "t" response (from student 1889):
A sample "v" response, with diagram only (from student 1213):
20090314
Astronomy midterm question: near infrared telescope locations
Astronomy 210 Midterm 1, Spring Semester 2009
Cuesta College, San Luis Obispo, CA
(Electromagnetic spectrum provided on Midterm 1, with transparency of Earth's atmosphere indicated for different forms of light. Downward lengths of gray bars indicates amount transmitted through atmosphere.)
Where could you set up a telescope in order to detect near infrared light?
(A) On top of high mountains.
(B) At sea level.
(C) (Near infrared light is detectable at both locations.)
(D) (Near infrared light is not detectable at either location.)
Section 30676
(A) : 23 students
(B) : 2 students
(C) : 12 students
(D) : 0 students
Correct answer: (A)
Since the gray bar for near infrared light does not go all the way down through the atmosphere, this type of electromagnetic radiation cannot be detected at sea level, but will be at higher elevations (as well as in space).
"Difficulty level": 62% (including partial credit for multiple-choice)
Discrimination index (Aubrecht & Aubrecht, 1983): 0.27
Cuesta College, San Luis Obispo, CA
(Electromagnetic spectrum provided on Midterm 1, with transparency of Earth's atmosphere indicated for different forms of light. Downward lengths of gray bars indicates amount transmitted through atmosphere.)
Where could you set up a telescope in order to detect near infrared light?
(A) On top of high mountains.
(B) At sea level.
(C) (Near infrared light is detectable at both locations.)
(D) (Near infrared light is not detectable at either location.)
Section 30676
(A) : 23 students
(B) : 2 students
(C) : 12 students
(D) : 0 students
Correct answer: (A)
Since the gray bar for near infrared light does not go all the way down through the atmosphere, this type of electromagnetic radiation cannot be detected at sea level, but will be at higher elevations (as well as in space).
"Difficulty level": 62% (including partial credit for multiple-choice)
Discrimination index (Aubrecht & Aubrecht, 1983): 0.27
20090313
Waxing crescent Moon and Venus
090227-1080353
http://www.flickr.com/photos/waiferx/3320098270/
Originally uploaded by Waifer X
090227-1080352
http://www.flickr.com/photos/waiferx/3320097310/
Originally uploaded by Waifer X
090227-1080351
http://www.flickr.com/photos/waiferx/3320096040/
Originally uploaded by Waifer X
Waxing crescent Moon and Venus on February 27, 2009, taken from the San Luis Obispo High School parking lot, San Luis Obispo, CA.
http://www.flickr.com/photos/waiferx/3320098270/
Originally uploaded by Waifer X
090227-1080352
http://www.flickr.com/photos/waiferx/3320097310/
Originally uploaded by Waifer X
090227-1080351
http://www.flickr.com/photos/waiferx/3320096040/
Originally uploaded by Waifer X
Waxing crescent Moon and Venus on February 27, 2009, taken from the San Luis Obispo High School parking lot, San Luis Obispo, CA.
20090312
The San Luis Obispo High School planetarium
090227-1080327
http://www.flickr.com/photos/waiferx/3320087404//
Originally uploaded by Waifer X
090227-1080328
http://www.flickr.com/photos/waiferx/3320090334/
Originally uploaded by Waifer X
Two views of the projector of the San Luis Obispo High School planetarium, San Luis Obispo, CA.
090227-1080343
http://www.flickr.com/photos/waiferx/3319266399/
Originally uploaded by Waifer X
The San Luis Obispo County Regional Airport silhouette on the eastern horizon of the planetarium.
090227-1080344
http://www.flickr.com/photos/waiferx/3319268891/
Originally uploaded by Waifer X
Bishop's Peak, Cerro Romauldo, Camp San Luis Obispo (CSLO), Hollister Peak, Morro Rock, and the Morro Bay Power Plant silhouette on the western horizon of the planetarium.
http://www.flickr.com/photos/waiferx/3320087404//
Originally uploaded by Waifer X
090227-1080328
http://www.flickr.com/photos/waiferx/3320090334/
Originally uploaded by Waifer X
Two views of the projector of the San Luis Obispo High School planetarium, San Luis Obispo, CA.
090227-1080343
http://www.flickr.com/photos/waiferx/3319266399/
Originally uploaded by Waifer X
The San Luis Obispo County Regional Airport silhouette on the eastern horizon of the planetarium.
090227-1080344
http://www.flickr.com/photos/waiferx/3319268891/
Originally uploaded by Waifer X
Bishop's Peak, Cerro Romauldo, Camp San Luis Obispo (CSLO), Hollister Peak, Morro Rock, and the Morro Bay Power Plant silhouette on the western horizon of the planetarium.
20090311
Education research: Rudolph Presentation "A National Study on the Effect of Interactive Learning in the Astro 101 Classroom"
Dr. Alexander L. Ruldolph (Associate Professor of Physics, Physics Department, California State Polytechnic University, Pomona) presents findings on peer instruction and lecture tutorials in introductory astronomy classes ("A National Study on the Effect of Interactive Learning in the Astro 101 Classroom") on February 26, 2009 at California Polytechnic State University, San Luis Obispo, CA. Photos by Cuesta College Physical Sciences division instructor Dr. Patrick M. Len.
090226-1080305
http://www.flickr.com/photos/waiferx/3320075216/
Originally uploaded by Waifer X
Radio frequency iClicker electronic response units.
090226-1080308
http://www.flickr.com/photos/waiferx/3320077038/
Originally uploaded by Waifer X
Dr. John Keller (California Polytechnic State University, San Luis Obispo) introduces Dr. Rudolph.
090226-1080313
http://www.flickr.com/photos/waiferx/3320078438/
Originally uploaded by Waifer X
Dr. Rudolph summarizes how instructors can get involved with implementing and evaluating interactive learning techniques in introductory astronomy courses.
090226-1080320
http://www.flickr.com/photos/waiferx/3319254389/
Originally uploaded by Waifer X
Dr. Rudolph answers questions from the audience at the end of the presentation, facilitated by Dr. Keller.
090226-1080305
http://www.flickr.com/photos/waiferx/3320075216/
Originally uploaded by Waifer X
Radio frequency iClicker electronic response units.
090226-1080308
http://www.flickr.com/photos/waiferx/3320077038/
Originally uploaded by Waifer X
Dr. John Keller (California Polytechnic State University, San Luis Obispo) introduces Dr. Rudolph.
090226-1080313
http://www.flickr.com/photos/waiferx/3320078438/
Originally uploaded by Waifer X
Dr. Rudolph summarizes how instructors can get involved with implementing and evaluating interactive learning techniques in introductory astronomy courses.
090226-1080320
http://www.flickr.com/photos/waiferx/3319254389/
Originally uploaded by Waifer X
Dr. Rudolph answers questions from the audience at the end of the presentation, facilitated by Dr. Keller.
20090310
Physics quiz question: unsticking a book from rest
Physics 205A Quiz 3, spring semester 2009
Cuesta College, San Luis Obispo, CA
Cf. Giambattista/Richardson/Richardson, Physics, 2/e, Comprehensive Problem 4.124
A 5.0 kg book on a horizontal table is initially at rest. The coefficient of static friction is 0.33. The coefficient of kinetic friction is 0.27. What is the magnitude of the minimum horizontal applied force required to make the book start to slide?
(A) 3 N.
(B) 13 N.
(C) 16 N.
(D) 49 N.
Correct answer (highlight to unhide): (C)
The box has two vertical forces acting on it:
The book has two horizontal forces acting on it:
fs,max = µs·N = µs·m·g = (0.33)(5.0 kg)(9.80 N/kg) = 16 N,
such that the applied force Fapplied magnitude must exceed 16 N in order to unstick the book.
(Response (D) is the magnitude of the weight force: w = m·g; response (B) is the magnitude of the kinetic friction force on the book after it has been unstuck and sliding: fk = µk·N = µk·m·g; while response (A) is the result of the difference fs,max – fk.)
Student responses
Sections 30880, 30881
(A) : 3 students
(B) : 5 students
(C) : 32 students
(D) : 6 students
Success level: 66%
Discrimination index (Aubrecht & Aubrecht, 1983): 0.62
Cuesta College, San Luis Obispo, CA
Cf. Giambattista/Richardson/Richardson, Physics, 2/e, Comprehensive Problem 4.124
A 5.0 kg book on a horizontal table is initially at rest. The coefficient of static friction is 0.33. The coefficient of kinetic friction is 0.27. What is the magnitude of the minimum horizontal applied force required to make the book start to slide?
(A) 3 N.
(B) 13 N.
(C) 16 N.
(D) 49 N.
Correct answer (highlight to unhide): (C)
The box has two vertical forces acting on it:
Weight force of Earth on book (downwards, magnitude w = m·g = 49 N).Because the suitcase is stationary in the vertical direction, these two forces are equal in magnitude and opposite in direction, due to Newton's first law.
Normal force of floor on book (upwards, magnitude N = 49 N).
The book has two horizontal forces acting on it:
Friction (static or kinetic) force of floor on book (to the left).In order to "unstick" the book, the horizontally applied force must overcome the maximum possible static friction force magnitude:
External applied force on book (to the right).
fs,max = µs·N = µs·m·g = (0.33)(5.0 kg)(9.80 N/kg) = 16 N,
such that the applied force Fapplied magnitude must exceed 16 N in order to unstick the book.
(Response (D) is the magnitude of the weight force: w = m·g; response (B) is the magnitude of the kinetic friction force on the book after it has been unstuck and sliding: fk = µk·N = µk·m·g; while response (A) is the result of the difference fs,max – fk.)
Student responses
Sections 30880, 30881
(A) : 3 students
(B) : 5 students
(C) : 32 students
(D) : 6 students
Success level: 66%
Discrimination index (Aubrecht & Aubrecht, 1983): 0.62
20090309
Physics quiz question: horizontally-thrown projectile
Physics 205A Quiz 3, spring semester 2009
Cuesta College, San Luis Obispo, CA
Cf. Giambattista/Richardson/Richardson, Physics, 2/e, Problem 3.46
A ball is thrown off the edge of a cliff with an initial horizontal velocity. It lands on the ground below 1.9 s after it was thrown, at a horizontal distance of 32 m from the base of the cliff. Neglect air resistance. Choose up to be the +y direction. The initial (horizontal) speed of the ball is:
(A) 5.2 m/s.
(B) 17 m/s.
(C) 19 m/s.
(D) 61 m/s.
Correct answer (highlight to unhide): (B)
The following quantities are given (or assumed to be known):
(x0 = 0 m),
(y0 = 0 m),
(t0 = 0 s),
t = 1.9 s,
x = +32 m,
v0y = 0 m/s,
ay = –9.80 m/s2.
So in the equations for projectile motion, the following quantities are unknown, or are to be explicitly solved for:
x = v0x·t,
vy = v0y + ay·t,
y = (1/2)·(vy + v0y)·t,
y = v0y·t + (1/2)·ay·(t)2,
vy2 – v0y2 = 2·ay·y.
With the unknown quantity v0x to be solved for appearing in the fourth equation, with all other quantities given (or assumed to be known), then the initial horizontal velocity can be solved for:
v0x = x/t = +16.84 m/s,
of which the magnitude (speed) is 17 m/s to two significant digits.
(Response (A) is the result of (9.80 m/s2)/t; response (C) is (9.80 m/s2)·t, which would be the magnitude of the vertical (downwards) velocity of the ball 1.9 s after it was thrown; while response (D) is x·t.)
Student responses
Sections 30880, 30881
(A) : 1 student
(B) : 36 students
(C) : 11 students
(D) : 0 students
Success level: 75%
Discrimination index (Aubrecht & Aubrecht, 1983): 0.43
Cuesta College, San Luis Obispo, CA
Cf. Giambattista/Richardson/Richardson, Physics, 2/e, Problem 3.46
A ball is thrown off the edge of a cliff with an initial horizontal velocity. It lands on the ground below 1.9 s after it was thrown, at a horizontal distance of 32 m from the base of the cliff. Neglect air resistance. Choose up to be the +y direction. The initial (horizontal) speed of the ball is:
(A) 5.2 m/s.
(B) 17 m/s.
(C) 19 m/s.
(D) 61 m/s.
Correct answer (highlight to unhide): (B)
The following quantities are given (or assumed to be known):
(x0 = 0 m),
(y0 = 0 m),
(t0 = 0 s),
t = 1.9 s,
x = +32 m,
v0y = 0 m/s,
ay = –9.80 m/s2.
So in the equations for projectile motion, the following quantities are unknown, or are to be explicitly solved for:
x = v0x·t,
vy = v0y + ay·t,
y = (1/2)·(vy + v0y)·t,
y = v0y·t + (1/2)·ay·(t)2,
vy2 – v0y2 = 2·ay·y.
With the unknown quantity v0x to be solved for appearing in the fourth equation, with all other quantities given (or assumed to be known), then the initial horizontal velocity can be solved for:
v0x = x/t = +16.84 m/s,
of which the magnitude (speed) is 17 m/s to two significant digits.
(Response (A) is the result of (9.80 m/s2)/t; response (C) is (9.80 m/s2)·t, which would be the magnitude of the vertical (downwards) velocity of the ball 1.9 s after it was thrown; while response (D) is x·t.)
Student responses
Sections 30880, 30881
(A) : 1 student
(B) : 36 students
(C) : 11 students
(D) : 0 students
Success level: 75%
Discrimination index (Aubrecht & Aubrecht, 1983): 0.43
20090308
Astronomy quiz question: adaptive optics
Astronomy 210 Quiz 3, Spring Semester 2009
Cuesta College, San Luis Obispo, CA
Adaptive optics is used in modern optical telescopes to improve:
(A) light-gathering power.
(B) resolving power.
(C) magnifying power.
(D) the amount of radiation transmitted through the atmosphere.
Correct answer: (B)
The secondary mirror of an optical telescope can be "warped" in real-time in order to compensating for the poor seeing caused by atmospheric turbulence, thus increasing the effective resolving power.
Section 30676
(A) : 12 students
(B) : 32 students
(C) : 13 students
(D) : 5 students
"Success level": 56% (including partial credit for multiple-choice)
Discrimination index (Aubrecht & Aubrecht, 1983): 0.51
Previous post:
Cuesta College, San Luis Obispo, CA
Adaptive optics is used in modern optical telescopes to improve:
(A) light-gathering power.
(B) resolving power.
(C) magnifying power.
(D) the amount of radiation transmitted through the atmosphere.
Correct answer: (B)
The secondary mirror of an optical telescope can be "warped" in real-time in order to compensating for the poor seeing caused by atmospheric turbulence, thus increasing the effective resolving power.
Section 30676
(A) : 12 students
(B) : 32 students
(C) : 13 students
(D) : 5 students
"Success level": 56% (including partial credit for multiple-choice)
Discrimination index (Aubrecht & Aubrecht, 1983): 0.51
Previous post:
- Astronomy quiz question: adaptive optics
Fall Semester 2008
20090307
Astronomy quiz question: primary mirror focal length
Astronomy 210 Quiz 3, Spring Semester 2009
Cuesta College, San Luis Obispo, CA
What power of an optical telescope is affected by the focal length of the primary mirror?
(A) Light-gathering power.
(B) Resolving power.
(C) Magnifying power.
(D) (None of the above choices.)
Section 30676
(A) : 12 students
(B) : 19 students
(C) : 31 students
(D) : 0 students
Correct answer: (C)
The magnification of an optical telescope depends on the ratio of the focal lengths of the primary lens (or mirror) and the eyepiece. The light-gathering power and the resolving power of an optical telescope depend only on the properties of the primary lens (or mirror), specifically the area and diameter, respectively.
"Difficulty level": 54% (including partial credit for multiple-choice)
Discrimination index (Aubrecht & Aubrecht, 1983): 0.66
Cuesta College, San Luis Obispo, CA
What power of an optical telescope is affected by the focal length of the primary mirror?
(A) Light-gathering power.
(B) Resolving power.
(C) Magnifying power.
(D) (None of the above choices.)
Section 30676
(A) : 12 students
(B) : 19 students
(C) : 31 students
(D) : 0 students
Correct answer: (C)
The magnification of an optical telescope depends on the ratio of the focal lengths of the primary lens (or mirror) and the eyepiece. The light-gathering power and the resolving power of an optical telescope depend only on the properties of the primary lens (or mirror), specifically the area and diameter, respectively.
"Difficulty level": 54% (including partial credit for multiple-choice)
Discrimination index (Aubrecht & Aubrecht, 1983): 0.66
20090306
Astronomy quiz question: replacing telescope eyepiece
Astronomy 210 Quiz 3, Spring Semester 2009
Cuesta College, San Luis Obispo, CA
The eyepiece of an optical telescope is replaced by an eyepiece with different characteristics. This change affects the __________ of the telescope.
(A) light-gathering power.
(B) resolving power.
(C) magnifying power.
(D) (More than one of the above choices.)
Section 30674
(A) : 1 student
(B) : 6 students
(C) : 19 students
(D) : 12 students
Correct answer: (C)*
The magnification of an optical telescope depends on the ratio of the focal lengths of the primary lens (or mirror) and the eyepiece. The light-gathering power and the resolving power of an optical telescope depend only on the properties of the primary lens (or mirror), specifically the area and diameter, respectively.
"Difficulty level": 52% (including partial credit for multiple-choice)
Discrimination index (Aubrecht & Aubrecht, 1983): 0.38
*Corrected from an earlier typographical error, as per student comment.
Cuesta College, San Luis Obispo, CA
The eyepiece of an optical telescope is replaced by an eyepiece with different characteristics. This change affects the __________ of the telescope.
(A) light-gathering power.
(B) resolving power.
(C) magnifying power.
(D) (More than one of the above choices.)
Section 30674
(A) : 1 student
(B) : 6 students
(C) : 19 students
(D) : 12 students
Correct answer: (C)*
The magnification of an optical telescope depends on the ratio of the focal lengths of the primary lens (or mirror) and the eyepiece. The light-gathering power and the resolving power of an optical telescope depend only on the properties of the primary lens (or mirror), specifically the area and diameter, respectively.
"Difficulty level": 52% (including partial credit for multiple-choice)
Discrimination index (Aubrecht & Aubrecht, 1983): 0.38
*Corrected from an earlier typographical error, as per student comment.
Education research: preliminary feedback on clickers (Chemistry 210FL, Cuesta College, Spring Semester 2009)
Cuesta College students taking Chemistry 210FL (introductory chemistry) at Cuesta College, San Luis Obispo, CA use clickers (Classroom Performance System, einstruction.com) during lecture.
Through the fifth and sixth weeks of instruction, students were given the opportunity to evaluate the instructional components of the course, and the use of clickers in an online "Learning Resource Survey" hosted by SurveyMonkey.com. Questions from section II are adapted from the Student Assessment of Learning Gains (SALG) survey (developed by Elaine Seymour, Wisconsin Center for Education Research, University of Wisconsin-Madison), and questions from section III (III.1, III.3, III.5, and III.7) were adapted from a "Clicker Attitude Survey" (N. W. Reay, Lei Bao, and Pengfei Li, Physics Education Research Group, Ohio State University).
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.
Through the fifth and sixth weeks of instruction, students were given the opportunity to evaluate the instructional components of the course, and the use of clickers in an online "Learning Resource Survey" hosted by SurveyMonkey.com. Questions from section II are adapted from the Student Assessment of Learning Gains (SALG) survey (developed by Elaine Seymour, Wisconsin Center for Education Research, University of Wisconsin-Madison), and questions from section III (III.1, III.3, III.5, and III.7) were adapted from a "Clicker Attitude Survey" (N. W. Reay, Lei Bao, and Pengfei Li, Physics Education Research Group, Ohio State University).
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.
Learning Resource SurveyThe following are all of the student responses to this question, verbatim and unedited.
Cuesta College
Chemistry 210FL Spring Semester 2009 sections 30729, 30730, 30731
(N = 39)
I. In order to receive credit for completing this survey,
first enter your first and last name below:
____
II. How much did each of the following aspects of the class help
your learning?
II.1 Lecture by instructor.
1. Strongly disagree 0 :
2. Disagree 1 : *
3. Neutral 5 : *****
4. Agree 17 : ***************** [4.2 +/- 0.8]
5. Strongly agree 15 : ***************
II.2 Working in groups on FAL (Facilitated Assisted Learning) activities.
1. Strongly disagree 2 : **
2. Disagree 2 : **
3. Neutral 6 : ******
4. Agree 7 : *******
5. Strongly agree 22 : ********************** [4.2 +/- 1.2]
II.3 Using clickers to participate in class.
1. Strongly disagree 2 : **
2. Disagree 3 : ***
3. Neutral 9 : *********
4. Agree 17 : ***************** [3.7 +/- 1.1]
5. Strongly agree 8 : ********
II.4 Reading the textbook.
1. Strongly disagree 1 : *
2. Disagree 3 : ***
3. Neutral 6 : ******
4. Agree 25 : ************************* [3.7 +/- 0.8]
5. Strongly agree 4 : ****
II.5 Demonstrations/videos in class.
1. Strongly disagree 0 :
2. Disagree 1 : *
3. Neutral 16 : **************** [3.7 +/- 0.8]
4. Agree 15 : ***************
5. Strongly agree 7 : *******
II.6 Interacting with other students during class.
1. Strongly disagree 0 :
2. Disagree 1 : *
3. Neutral 11 : ***********
4. Agree 12 : ************
5. Strongly agree 15 : *************** [4.1 +/- 0.9]
II.7 Interacting with other students outside of class.
1. Strongly disagree 1 : *
2. Disagree 1 : *
3. Neutral 10 : **********
4. Agree 14 : ************** [3.9 +/- 1.0]
5. Strongly agree 13 : *************
III. Answer the following statements which may or may not describe
your beliefs about the use of clickers in this class.
III.1 I like using clickers.
1. Strongly disagree 2 : **
2. Disagree 3 : ***
3. Neutral 14 : ************** [3.5 +/- 1.1]
4. Agree 13 : *************
5. Strongly agree 7 : *******
III.2 Clickers helped me understand lectures better.
1. Strongly disagree 3 : ***
2. Disagree 6 : ******
3. Neutral 18 : ****************** [3.1 +/- 1.1]
4. Agree 8 : ********
5. Strongly agree 4 : ****
III.3 I would recommend using clickers in future semesters of this class.
1. Strongly disagree 3 : ***
2. Disagree 2 : **
3. Neutral 13 : *************
4. Agree 16 : **************** [3.5 +/- 1.1]
5. Strongly agree 5 : *****
III.4 I will avoid other classes using clickers in future semesters.
1. Strongly disagree 12 : ************
2. Disagree 14 : ************** [2.2 +/- 2.2]
3. Neutral 8 : ********
4. Agree 2 : **
5. Strongly agree 2 : **
III.5 Clickers were a positive experience.
1. Strongly disagree 2 : **
2. Disagree 3 : ***
3. Neutral 14 : **************
4. Agree 15 : *************** [3.5 +/- 1.0]
5. Strongly agree 5 : *****
III.6 Too much time in class was spent using clickers.
1. Strongly disagree 7 : *******
2. Disagree 22 : ********************** [2.2 +/- 1.4]
3. Neutral 6 : ******
4. Agree 2 : **
5. Strongly agree 2 : **
III.7 Too many clicker questions were asked.
1. Strongly disagree 9 : *********
2. Disagree 20 : ******************** [2.2 +/- 1.7]
3. Neutral 7 : *******
4. Agree 1 : *
5. Strongly agree 2 : **
III.8 Using clickers was difficult.
1. Strongly disagree 16 : ****************
2. Disagree 17 : ***************** [1.7 +/- 2.6]
3. Neutral 6 : ******
4. Agree 0 :
5. Strongly agree 0 :
IV. (Optional.) Please type in any comments you may have regarding
the use of clickers in Chemistry 210FL.
"I feel that the interactive learning among other students has been the most helpful. The lectures in class have been very clear and helpful in learning the concepts."
"I like using them, it is a quick way to get feedback on how I am doing on that particular subject. I think they are helpful to me in this class."
"I like that we get immediate results with the clickers.
"they are a neat idea, but scantrons are more cost effective. The cost of the clicker and registering it probably could have bought all the scantrons needed for the two years at Cuesta, and then some."
"Clickers are too expensive, we don't get nearly enough use out of them, not resell-worthy! I do believe: Clickers should be used as an alternative to paper and/or other supplies but in our class I have noticed that there is still a high rate of paper waste -- we used the printed answer sheet with A,B,C,D to answer in class questions, Also our most recent test had an unnecessary cover sheet, and the teacher uses paper instead of the projector to write pages and pages of notes every class. On top of all that, we had to buy over $200.00 worth of other supplies for this class. If the entire school promoted the use of clickers, i think they would be a great alternative learning method and the school would save money. If we are going to use clickers then we should be dedicated to using them, and incorporating them into as many things possible."
"Clickers are pretty helpful and I like that we get to work together with classmates. It really helps me fully comprehend how to do problems."
"The clickers were a very good way of quizzing to see what we know, but without the tense feeling of taking a test. I think there should be more clicker questions asked throughout the lecture, if time permits."
"Would be much more simple to just pay your membership fee when you buy your clicker, with your books. Not everyone has a credit card to pay for it online. Plus, it feels like your getting nickle and dimed. Money for ICH, money for labs, money for text, money for clicker, then money to pay for a membership."
"I think that the FAL actually needs to be longer because so far there has been a lot of info to cover and you have to do the homework anyway."
"I don't feel that the clickers really add much to the class except that they're fun buttons to push every now and again. In terms of extra learning experience, it doesn't help."
"I appreciate using clickers. My instructor (Kahane) was very helpful in explaining how to use the clickers."
"The only bad thing about the clickers is how expensive they end up being, especially if they will not be used in future classes."
"I think that they are not necessary, and VERY expensive for a college student. I beleive the concept is good and could be very helpful but it just doesnt seem necessary. We could do the same thing with peices of paper or raising our hand."
"Expensive to buy and register with no sell back option or any use in the future. Other schools use similar thing but is already in the classroom at every seat on a cord."
"I think that the clickers are fun! execpt when i forget mine... then i feel left out."
"i understand the clickers help the teachers to recieve immediate feedback and how they are beneficial to the class, i just don't like the fact that i had to buy something additional for the class and then pay again to register it. i felt like i was being nickled and dimed in a class that was already very expensive."
"I think the usage of clickers is positive and beneficial, but I do think they are a little expensive, and would be better if we could sell them back or reuse them for other classes."
"I think that the use of clickers is a good way to make sure students are keeping up on regular reading and assignments. I think how we can get the grades immediately and not waste paper. Talking about the clicker question also helps build relationships with other students in the class."
"clickers help the teacher and the student interact and know what each other was thinking. Trying to take a survey about any thing is a click away and we all can see the results fast. Some studnts wont ask a teacher a question even if they are confused. the clicker seems to side step this problem because clicker cause you to talk to your neighbor and get feed back.
I like using the clickers in class because I felt like they were kind of mini-tests, I felt like they were exercising what I had just learned of what a should have been learning. It keeps me on my toes."
"I really like the clickers, not only because it's a faster way of answering multiply choice questions, but also because we are given a chance to discuss the answers with people around us."
"It is a huge waste of money for us students to use that when we simply could just go over our papers out loud as a class. We have to pay for a lot of other stuff during school and the clicker is very unnecessary."
"I think clickers are a good tool to make sure students are doing homework and keeping up with class, however I don't feel they should be used in every class period. To me they should be used about once a week. In the end I don't mind them, I just feel that if I accidently miss class than I am going to miss points and I really am trying hard not to miss any points."
20090305
Astronomy quiz question: light pollution effects
Astronomy 210 Quiz 3, Spring Semester 2009
Cuesta College, San Luis Obispo, CA
What power of an optical telescope is affected by light pollution?
(A) Light-gathering power.
(B) Resolving power.
(C) Magnifying power.
(D) (None of the above choices.)
Section 30674
(A) : 25 students
(B) : 12 students
(C) : 1 student
(D) : 0 students
Correct answer: (A)
The light from natural sources (the Moon), and from man-made sources (skyglow from streetlights) affects the ability of optical telescopes to see dim objects, thus affecting its light-gathering power.
"Difficulty level": 69% (including partial credit for multiple-choice)
Discrimination index (Aubrecht & Aubrecht, 1983): 0.33
Cuesta College, San Luis Obispo, CA
What power of an optical telescope is affected by light pollution?
(A) Light-gathering power.
(B) Resolving power.
(C) Magnifying power.
(D) (None of the above choices.)
Section 30674
(A) : 25 students
(B) : 12 students
(C) : 1 student
(D) : 0 students
Correct answer: (A)
The light from natural sources (the Moon), and from man-made sources (skyglow from streetlights) affects the ability of optical telescopes to see dim objects, thus affecting its light-gathering power.
"Difficulty level": 69% (including partial credit for multiple-choice)
Discrimination index (Aubrecht & Aubrecht, 1983): 0.33
Education research: preliminary feedback on clickers (Cuesta College, Astronomy 210, Spring Semester 2009)
Cuesta College students taking Astronomy 210 (introductory astronomy) at Cuesta College, San Luis Obispo, CA use clickers (Classroom Performance System, einstruction.com) to engage in peer-interaction ("think-(pair)-share") discussion questions during lecture.
Through the fifth and sixth weeks of instruction (third and fourth weeks of using clickers), students were given the opportunity to evaluate the instructional components of the course, and the use of clickers in an online "Learning Resource Survey" hosted by SurveyMonkey.com. Questions from section II are adapted from the Student Assessment of Learning Gains (SALG) survey (developed by Elaine Seymour, Wisconsin Center for Education Research, University of Wisconsin-Madison), and questions from section III (III.1, III.3, III.5, and III.7) were adapted from a "Clicker Attitude Survey" (N. W. Reay, Lei Bao, and Pengfei Li, Physics Education Research Group, Ohio State University).
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.
Through the fifth and sixth weeks of instruction (third and fourth weeks of using clickers), students were given the opportunity to evaluate the instructional components of the course, and the use of clickers in an online "Learning Resource Survey" hosted by SurveyMonkey.com. Questions from section II are adapted from the Student Assessment of Learning Gains (SALG) survey (developed by Elaine Seymour, Wisconsin Center for Education Research, University of Wisconsin-Madison), and questions from section III (III.1, III.3, III.5, and III.7) were adapted from a "Clicker Attitude Survey" (N. W. Reay, Lei Bao, and Pengfei Li, Physics Education Research Group, Ohio State University).
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.
Learning Resource SurveyThe following are all of the student responses to this question, verbatim and unedited.
Cuesta College
Astronomy 210 Spring Semester 2009 sections 30674, 30676
(N = 49)
I. In order to receive credit for completing this survey,
first enter your first and last name below:
____
II. How much did each of the following aspects of the class help
your learning?
II.1 Lecture by instructor.
1. Strongly disagree 1 : *
2. Disagree 5 : *****
3. Neutral 8 : ********
4. Agree 21 : ********************* [3.9 +/- 1.0]
5. Strongly agree 14 : **************
II.2 Working in groups on in-class activities.
1. Strongly disagree 3 : ***
2. Disagree 3 : ***
3. Neutral 10 : **********
4. Agree 21 : ********************* [3.7 +/- 1.1]
5. Strongly agree 11 : ***********
II.3 Using clickers to participate in class.
1. Strongly disagree 0 :
2. Disagree 2 : **
3. Neutral 8 : ********
4. Agree 21 : ********************* [4.1 +/- 0.8]
5. Strongly agree 18 : ******************
II.4 Reading the textbook.
1. Strongly disagree 2 : **
2. Disagree 4 : ****
3. Neutral 13 : *************
4. Agree 20 : ******************** [3.7 +/- 1.0]
5. Strongly agree 10 : **********
II.5 Demonstrations/videos in class.
1. Strongly disagree 1 : *
2. Disagree 2 : **
3. Neutral 8 : ********
4. Agree 20 : ******************** [4.1 +/- 0.9]
5. Strongly agree 18 : ******************
II.6 Interacting with other students during class.
1. Strongly disagree 2 : **
2. Disagree 3 : **
3. Neutral 5 : *****
4. Agree 26 : ************************** [3.9 +/- 1.0]
5. Strongly agree 13 : *************
II.7 Interacting with other students outside of class.
1. Strongly disagree 2 : **
2. Disagree 10 : **********
3. Neutral 24 : ************************ [3.0 +/- 0.9]
4. Agree 11 : ***********
5. Strongly agree 1 : *
III. Answer the following statements which may or may not describe
your beliefs about the use of clickers in this class.
III.1 I like using clickers.
1. Strongly disagree 1 : *
2. Disagree 3 : ***
3. Neutral 6 : ******
4. Agree 24 : ************************ [4.0 +/- 0.9]
5. Strongly agree 15 : ***************
III.2 Clickers helped me understand lectures better.
1. Strongly disagree 0 :
2. Disagree 4 : ****
3. Neutral 8 : ********
4. Agree 30 : ****************************** [3.8 +/- 0.8]
5. Strongly agree 7 : *******
III.3 I would recommend using clickers in future semesters of this class.
1. Strongly disagree 0 :
2. Disagree 3 : ***
3. Neutral 6 : ******
4. Agree 27 : *************************** [4.0 +/- 0.8]
5. Strongly agree 13 : *************
III.4 I will avoid other classes using clickers in future semesters.
1. Strongly disagree 19 : *******************
2. Disagree 27 : *************************** [1.7 +/- 2.7]
3. Neutral 3 : ***
4. Agree 0 :
5. Strongly agree 0 :
III.5 Clickers were a positive experience.
1. Strongly disagree 0 :
2. Disagree 1 : *
3. Neutral 5 : *****
4. Agree 33 : ********************************* [4.1 +/- 0.6]
5. Strongly agree 10 : **********
III.6 Too much time in class was spent using clickers.
1. Strongly disagree 13 : *************
2. Disagree 27 : *************************** [2.0 +/- 2.0]
3. Neutral 5 : *****
4. Agree 4 : ****
5. Strongly agree 0 :
III.7 Too many clicker questions were asked.
1. Strongly disagree 14 : **************
2. Disagree 28 : **************************** [1.9 +/- 2.1]
3. Neutral 5 : *****
4. Agree 1 : *
5. Strongly agree 0 :
III.8 Using clickers was difficult.
1. Strongly disagree 31 : ******************************* [1.6 +/- 4.5]
2. Disagree 14 : **************
3. Neutral 1 : *
4. Agree 1 : *
5. Strongly agree 2 : **
IV. (Optional.) Please type in any comments you may have regarding
the use of clickers in Astronomy 210.
"Did I do this survey already, when you first announced it, or is this another one? The clickers are a great benefit for both the student and teacher. The student can print the clicker questions prior to class, and circle the answers in pencil, then correct them during lecture. This is a great study tool for the tests. For the teacher, they have immediate feedback and can better manage their lecture time. They can devote more time, or less time to a topic depending on the level of understanding the students are showing."
"I really do enjoy the clickers in class. It really is away of making me stop and really think over what I just learned and just how to apply that information to the questions asked. I would enjoy having the use of clickers in other classes like History."
"Clickers helped make the answers to questions clear. It helped the teacher see when the class wasn't understanding and gave many opportunities for students to discuss with each other the answers. It promoted discussions and made class interaction a necessity."
"I like the idea of clickers because you get to see how much the class is understanding overall."
"Clickers were fine in class because the instructor was able to help you then and there with things you had questions about. Sometimes I think though that some students were just messing around and purposefully clicking on wrong questions with the i don't know answer (i heard a kid next to me mention he was gonna click that option)."
"These are really cool devices!!"
"I like the clicker questions but when they are the first things that are done in class it is difficult to understand the marerial. I realize that we are supposed to read the chapter ahead of time but even when that has been done it is still difficult to answer questions about the lecture before the lecture. Same thing with in-class activities."
"Suggest to people they keep their clicker in their car or bag as to not forget it for class."
"I enjoy using clickers in class, they are an interactive learning tool that is very helpful"
"I think it's helpful at the end of lectures to use clickers but when we do it at the beginning before we have heard the lecture the questions we have to answer are sometimes difficult and i don't understand what we're talking about until the class is almost over or until the next class. I do read the chapters before class and for me, it's easier to see a powerpoint presentation then answer a bunch of questions."
"I like using clickers, but they are way too expensive."
"This was the first time I have used clickers in a class, for those that are finacially strapped it was a burden. But using them during class did help with some lecture that I was confused on."
"Never used a clicker before. Found it very useful in my learning. Can also see how helpful it is to the instructor in letting him know how well we are understanding the material."
"P-Dog ROCKS MY WORLD!!!!!!!!!"
"Clickers nice unless one has misplaced his or her's/ the batteries die."
"I think clickers are very helpful, but I would like the information to be described in greater detail before we begin the group projects, or are asked to answer clicker questions."
"the clicker questions arent that bad its just hard to get them to read so u end up pushing the button a hundred times."
"I like clickers :)"
"Clickers are a fun way to participate and interact in class."
"I think it's great that everyone has the opportunity to respond. It's good that the instructor knows where students stand. A downside for me is that I'm often in the minority of those who don't get it. I've never had such a hard time with a class & it's bothering me immensely, so I'm sure that's affecting my ratings."
"Clickers are a fun way to be active during class and it helps students try to answer study questions on their own, and if they are wrong they recieve information as to why a different answer is correct."
"I like using the clickers in class. It's a good way to participate without having to be called on unwillingly. It also lets you know that other people may answer the same way as you because a common misconception. I also really like the clickers because it is sometimes easier to have a student explination rather than a highly scientific explination."
"This was my first time using a clicker in class. I know that if we spent more time using the clickers then I would perform better on the quizzes. So in conclusion I believe we do not spend adequate time using the clickers. More Clicker-Time please!!! -Star Geek"
"I think using clickers is a good way to get the whole class involved without having to use up paper, its a more fun way to take a quiz."
"clickers are da bomb!!!"
"Clickers are a fun and interactive way to participate in class."