Cuesta College, San Luis Obispo, CA
The apparent magnitudes and absolute magnitudes of three stars are listed below.
| m apparent magnitude |
M absolute magnitude |
|
| Shaula | +2 | –4 |
| π Puppis | +3 | –5 |
| β Muscae | +3 | –2 |
Which star is located farther than 10 parsecs from Earth?
(A) Shaula.
(B) π Puppis.
(C) β Muscae.
(D) (Two of the above choices.)
(E) (All of the above choices.)
(F) (None of the above choices.)
Correct answer (highlight to unhide): (E)
Shaula appears to have a brightness of +2 as seen from its actual location from Earth, but when placed at the "fair" distance of 10 parsecs away, it becomes brighter (–4). This means that Shaula was brought closer to Earth when moved to 10 parsecs, and thus is located farther than 10 parsecs away from Earth.
Similarly, π Puppis and β Muscae also become brighter when moved from their actual locations from Earth to the "fair" distance of 10 parsecs away, so these stars are also brought closer to Earth when moved to 10 parsecs, and thus are also located farther than 10 parsecs away from Earth.
Section 70158
Exam code: quiz05Sbn3
(A) : 2 students
(B) : 9 students
(C) : 1 student
(D) : 2 students
(E) : 25 students
(F) : 5 students
Success level: 59% (including partial credit for multiple-choice)
Discrimination index (Aubrecht & Aubrecht, 1983): 0.67
Section 70160
Exam code: quiz05n3Rw
(A) : 0 students
(B) : 7 students
(C) : 0 students
(D) : 4 students
(E) : 15 students
(F) : 2 students
Success level: 55% (including partial credit for multiple-choice)
Discrimination index (Aubrecht & Aubrecht, 1983): 0.48
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