Multiple Choice
The "turnoff" point for a star cluster is the point in the H-R diagram occupied by the:
A) highest-mass main-sequence stars in the cluster.
B) stars undergoing (or about to undergo) the helium flash.
C) lowest-mass main-sequence stars in the cluster.
D) highest-mass stars that have not yet reached the main sequence.
Correct Answer:
Verified
Correct Answer:
Verified
Q7: A main-sequence star has a certain
Q8: Helium fusion begins in the core of
Q9: When the stars of the following
Q10: If you examine many main-sequence stars, the
Q11: The <sup>12</sup>C and <sup>16</sup>O, which now form
Q13: What is the expected main-sequence lifetime of
Q14: The H-R diagram for open star clusters
Q15: <sup>12</sup>C and <sup>16</sup>O are among the most
Q16: A helium flash occurs in the cores
Q17: After the helium flash in a red