Cuesta College, San Luis Obispo, CA
[20 points.] Consider a star with an apparent magnitude that is brighter than its absolute magnitude. Discuss whether this star is farther than 10 parsecs, exactly at 10 parsecs, or closer than 10 parsecs from the Earth. Explain your reasoning.
Solution and grading rubric:
- p = 20/20:
Correct. Discusses (a) how observations of absorption spectra classify stars as metal-poor, and (b) how production of metals in cores of massive and medium-mass stars is dispersed via type II/type Ia supernovae to be incorporated into the outer layers of subsequent generation stars. - r = 16/20:
Nearly correct (explanation weak, unclear or only nearly complete); includes extraneous/tangential information; or has minor errors. One topic is
complete/correct, other other is problematic. - t = 12/20:
Contains right ideas, but discussion is unclear/incomplete or contains major errors. Only one of two discussion topics is complete and correct, the other is missing or has serious errors (typically spectroscopy); or both topics have minor errors. - v = 8/20:
Limited relevant discussion of supporting evidence of at least some merit, but in an inconsistent or unclear manner. Discusses metal-poor stars as being old, but with conceptual errors; no discussion on spectroscopy - x = 4/20:
Implementation/application of ideas, but credit given for effort rather than merit. May discuss how metals are used to fuel a star; less metals would then indicate an older star that has used up all its metals. - y = 2/20:
Irrelevant discussion/effectively blank. - z = 0/20:
Blank.
Section 70158
p: 5 students
r: 6 students
t: 23 students
v: 14 students
x: 22 students
y: 1 student
z: 0 students
A sample "p" response (from student 0711):
A sample "t" response (from student 1990):
Another sample "t" response (from student 3259):
A sample "x" response (from student 7027):
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