Cuesta College, San Luis Obispo, CA
How far away are Star X and Star Y located from Earth?(A) Both stars are closer than 10 parsecs.
(B) Both stars are farther than 10 parsecs.
(C) Star X is closer than 10 parsecs, Star Y is farther than 10 parsecs.
(D) Star X is farther than 10 parsecs, Star Y is closer than 10 parsecs.
Correct answer: (A)
For Star X, its apparent magnitude of -1.0 is brighter than its absolute visual magnitude of 0.0. For Star Y, its apparent magnitude of 0.0 is also brighter than its absolute visual magnitude of +1.0. Both stars appear bright as seen from Earth, at their positions, and since conceptually bringing them to the "fair distance" of 10 parsecs would make them both dimmer, they must be located closer than 10 parsecs away from Earth.
Section 30676
(A) : 18 students
(B) : 2 students
(C) : 11 students
(D) : 10 students
"Success level": 48% (including partial credit for multiple-choice)
Discrimination index (Aubrecht & Aubrecht, 1983): 0.45
Exam code: quiz04s0sO
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