Question: Which of the following main sequence stars would be the most massive?

Answer Choices:
M2
F6
K2
O9
A4

Answer: O9

 

Question: What core temperature is required for helium fusion to occur?

Answer Choices:
100 million K
10 million K
15 million K
10 billion K

Answer: 100 million K

 

Question: For a Sun-sized star, …

Answer Choices:
Core fusion will stop when a carbon core is formed
Core fusion will stop when an iron core is formed
Core fusion will stop when a helium core is formed
All core fusion will cease after the main sequence stage

Answer: Core fusion will stop when a carbon core is formed

 

Question: Which of the following main sequence stars would be the coolest?

Answer Choices:
K3
A9
G2
O8
F7

Answer: K3

 

Question: Which of the following stages is best explained as the outer layers of a star blown into space and illuminated by a hot central star?

Answer Choices:
Red supergiant
Helium flash
Planetary nebula
Red giant

Answer: Planetary nebula

 

Question: Which of the following main sequence stars is most likely to undergo a helium flash later in its evolution?

Answer Choices:
O1
G9
B0

Answer: G9

 

Question: Compared to the Sun a Red Giant star is…

Answer Choices:
Brighter in apparent magnitude
Higher in luminosity
Larger in radius
More dense
Higher in surface temperature

Answer: Higher in luminosity, Larger in radius, More dense

 

Question: The red giant stage occurs when…

Answer Choices:
The star is finished burning helium
The star stops hydrogen shell burning
Hydrogen shell burning causes the star to expand
The star starts burning helium

Answer: Hydrogen shell burning causes the star to expand

 

Question: If a cluster shows a main sequence turnoff point at G2, what is the approximate age of the cluster?

Answer Choices:
2.07 billion years old
10 million years old
4.5 billion years old
10 billion years old

Answer: 10 billion years old

 

Question: Which of the following would be most likely to show a main sequence turnoff point around F9?

Answer Choices:
OB Stellar Association
Senior Cluster
Young Open Cluster
Globular Cluster

Answer: Globular Cluster

 

Question: A star is no longer considered a main sequence star when…

Answer Choices:
A higher tier comes along
It starts fusing helium in its core
A younger star comes along
A more massive star comes along
It stops fusing hydrogen in its core

Answer: I. t stops fusing hydrogen in its core