20150518

Astronomy quiz question: red dwarf nucleosynthesis?

Astronomy 210 Quiz 7, spring semester 2015
Cuesta College, San Luis Obispo, CA

A red dwarf produced the:
(A) hydrogen in the sun.
(B) gold and silver in Earth's crust.
(C) heat inside Earth's core.
(D) lithium in car batteries.
(E) (More than one of the above choices.)
(F) (None of the above choices.)

Correct answer (highlight to unhide): (F)

A red dwarf is a low-mass main sequence star, which produces energy from fusing hydrogen into helium during its (extremely long) main sequence lifetime, which is so long (50+ billion years) that none have yet died, as it is longer than the age of the universe (14 billion years). Thus no atoms from a red dwarf have ever been released to be incorporated into the formation of our solar system.

Section 30674
Exam code: quiz07Ctlu
(A) : 3 students
(B) : 2 students
(C) : 1 student
(D) : 2 students
(E) : 8 students
(F) : 20 students

Success level: 57% (including partial credit for multiple-choice)
Discrimination index (Aubrecht & Aubrecht, 1983): 0.40

Section 30676
Exam code: quiz07Ctlu
(A) : 4 students
(B) : 0 students
(C) : 2 students
(D) : 1 student
(E) : 15 students
(F) : 21 students

Success level: 49% (including partial credit for multiple-choice)
Discrimination index (Aubrecht & Aubrecht, 1983): 0.82

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