1|Page
ASTRONOMY 1010 FINAL EXAM LATEST 2025 ACTUAL EXAM WITH
COMPLETE QUESTIONS AND CORRECT DETAILED ANSWERS (100%
VERIFIED ANSWERS) |ALREADY GRADED A+| ||PROFESSOR
VERIFIED|| ||BRANDNEW!!!||
Which two energy sources can help a star maintain its internal
thermal pressure?
A) nuclear fusion and chemical reactions
B) nuclear fission and gravitational contraction
C) nuclear fusion and gravitational contraction
D) nuclear fusion and nuclear fission
E) chemical reactions and gravitational contraction - ANSWER-C)
nuclear fusion and gravitational contraction
What is the source of luminosity for protostars that have not yet
become hot enough for fusion in their cores?
A) light absorbed from nearby stars
B) fusion in their low-density outer layers
C) fission from concentrated radioactive elements
D) gravitational energy released by infalling matter - ANSWER-D)
Gravitational energy released by infalling matter
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What can we learn about a star from its life track on an H-R
diagram?
A) where it is located
B) what surface temperature and luminosity it will have at each
stage of its life
C) how long ago it was born
D) when it will die
E) all of the above - ANSWER-B) what surface temperature and
luminosity it will have at each stage of its life
Which of the following statements about degeneracy pressure is
not true?
A) Degeneracy pressure can halt gravitational contraction of a
star even when no fusion is occurring in
the core.
B) Degeneracy pressure varies with the temperature of the star.
C) Degeneracy pressure keeps any protostar less than 0.08 solar
mass from becoming a true, hydrogen-fusing star.
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D) Degeneracy pressure is a consequence of the laws of
quantum me - ANSWER-B) Degeneracy pressure varies with the
temperature of the star
What percentage of a star's total lifetime is spent on the main
sequence?
A) 10% B) 20% C) 50% D) 90% E) 100% - ANSWER-D) 90%
What happens when a star like the sun exhausts its core
hydrogen supply?
A) Its core contracts, but its outer layers expand and the star
becomes bigger and brighter.
B) Its core contracts, with the star becoming hotter and brighter.
C) The core expands, and the star becomes bigger but dimmer.
D) The core contracts, with the star becoming smaller and
dimmer.
E) Its core contracts, but its outer layers expand and the star
becomes bigger but cooler and therefore
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remains at the same brightness. - ANSWER-A) Its core contracts,
but its outer layers expand and the star becomes bigger and
brighter
Helium fusion directly results in the formation of
A) nitrogen. B) carbon. C) iron. D) hydrogen - ANSWER-B)
Carbon
What happens after the helium flash in the core of a star?
A) The star starts to fuse helium in a shell outside the core.
B) The core suddenly contracts.
C) The core stops fusing helium.
D) The core quickly heats up and expands as helium fusion
begins all at once throughout the core.
E) The star breaks apart in a violent explosion. - ANSWER-D)
The core quickly heats up and expands as helium fusion begins
all at once throughout the core
Which of the following sequences correctly describes the stages
of life for a one solar mass star?
ASTRONOMY 1010 FINAL EXAM LATEST 2025 ACTUAL EXAM WITH
COMPLETE QUESTIONS AND CORRECT DETAILED ANSWERS (100%
VERIFIED ANSWERS) |ALREADY GRADED A+| ||PROFESSOR
VERIFIED|| ||BRANDNEW!!!||
Which two energy sources can help a star maintain its internal
thermal pressure?
A) nuclear fusion and chemical reactions
B) nuclear fission and gravitational contraction
C) nuclear fusion and gravitational contraction
D) nuclear fusion and nuclear fission
E) chemical reactions and gravitational contraction - ANSWER-C)
nuclear fusion and gravitational contraction
What is the source of luminosity for protostars that have not yet
become hot enough for fusion in their cores?
A) light absorbed from nearby stars
B) fusion in their low-density outer layers
C) fission from concentrated radioactive elements
D) gravitational energy released by infalling matter - ANSWER-D)
Gravitational energy released by infalling matter
,2|Page
What can we learn about a star from its life track on an H-R
diagram?
A) where it is located
B) what surface temperature and luminosity it will have at each
stage of its life
C) how long ago it was born
D) when it will die
E) all of the above - ANSWER-B) what surface temperature and
luminosity it will have at each stage of its life
Which of the following statements about degeneracy pressure is
not true?
A) Degeneracy pressure can halt gravitational contraction of a
star even when no fusion is occurring in
the core.
B) Degeneracy pressure varies with the temperature of the star.
C) Degeneracy pressure keeps any protostar less than 0.08 solar
mass from becoming a true, hydrogen-fusing star.
,3|Page
D) Degeneracy pressure is a consequence of the laws of
quantum me - ANSWER-B) Degeneracy pressure varies with the
temperature of the star
What percentage of a star's total lifetime is spent on the main
sequence?
A) 10% B) 20% C) 50% D) 90% E) 100% - ANSWER-D) 90%
What happens when a star like the sun exhausts its core
hydrogen supply?
A) Its core contracts, but its outer layers expand and the star
becomes bigger and brighter.
B) Its core contracts, with the star becoming hotter and brighter.
C) The core expands, and the star becomes bigger but dimmer.
D) The core contracts, with the star becoming smaller and
dimmer.
E) Its core contracts, but its outer layers expand and the star
becomes bigger but cooler and therefore
, 4|Page
remains at the same brightness. - ANSWER-A) Its core contracts,
but its outer layers expand and the star becomes bigger and
brighter
Helium fusion directly results in the formation of
A) nitrogen. B) carbon. C) iron. D) hydrogen - ANSWER-B)
Carbon
What happens after the helium flash in the core of a star?
A) The star starts to fuse helium in a shell outside the core.
B) The core suddenly contracts.
C) The core stops fusing helium.
D) The core quickly heats up and expands as helium fusion
begins all at once throughout the core.
E) The star breaks apart in a violent explosion. - ANSWER-D)
The core quickly heats up and expands as helium fusion begins
all at once throughout the core
Which of the following sequences correctly describes the stages
of life for a one solar mass star?
