Astronomy quiz question: HR 511

Astronomy 210 Quiz 4, fall semester 2012
Cuesta College, San Luis Obispo, CA

HR 511 is a star that is located 10 parsecs away from Earth. If HR 511 were moved to a location 12 parsecs away, its apparent magnitude m would __________, while its absolute visual magnitude MV would __________.
(A) get dimmer; not change.
(B) get brighter; not change.
(C) not change; get dimmer.
(D) not change; get brighter.

Correct answer: (A)

The apparent magnitude of HR 511, which is the brightness as seen from Earth, will get dimmer as it is moved farther away from 10 parsecs to 12 parsecs. The absolute visual magnitude, which is the intrinsic brightness, will remain the same no matter where HR 511 is located.

Section 70158
Exam code: quiz04Spr6
(A) : 22 students
(B) : 1 student
(C) : 11 students
(D) : 1 student

Success level: 65% (including partial credit for multiple-choice)
Discrimination index (Aubrecht & Aubrecht, 1983): 0.78

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