ISP 205 Exam 3 2024/2025 Exam
Questions and Answers | 100% Pass
Which two processes can generate energy to help a star maintain its
internal thermal pressure?
nuclear fission and supernova
nuclear fusion and supernova
nuclear fusion and nuclear fission
nuclear fusion and gravitational contraction - 🧠ANSWER ✔✔nuclear fusion
and gravitational contraction
Our Sun is considered to be a _________.
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STATEMENT. ALL RIGHTS RESERVED
,low-mass star
brown dwarf
high-mass star
intermediate-mass star - 🧠ANSWER ✔✔low-mass star
Which process is required to allow a gravitationally-collapsing gas cloud to
continue to collapse?
The cloud must trap most of its thermal energy.
New dust particles must continually be made in the cloud.
The cloud must radiate much of its thermal energy.
The cloud must collide with other clouds. - 🧠ANSWER ✔✔The cloud must
radiate much of its thermal energy.
Angular momentum plays an important role in star formation. Which of the
following characteristics of a protostellar system is probably not strongly
affected by the star's angular momentum?
the existence of protostellar jets
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,the formation of a protostellar disk
the onset of core hydrogen fusion
the strength of protostellar winds - 🧠ANSWER ✔✔the onset of core
hydrogen fusion
Generally speaking, how does the surface temperature and luminosity of a
protostar compare to the surface temperature and luminosity of the main-
sequence star it becomes?
A main-sequence star is hotter and dimmer than it was as a protostar.
A main-sequence star is cooler and dimmer than it was as a protostar.
A main-sequence star is cooler and brighter than it was as a protostar.
A main-sequence star is hotter and brighter than it was as a protostar. -
🧠ANSWER ✔✔A main-sequence star is hotter and dimmer than it was as a
protostar.
Consider a large molecular cloud that will give birth to a cluster of stars.
Which of the following would you expect to be true?
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, All the stars in the cluster will become main-sequence stars at about the
same time.
A few massive stars will form, live, and die before the majority of the star's
clusters even complete their protostar stage.
All the stars in the cluster will have approximately the same luminosity and
surface temperature.
All the stars in the cluster will be of about the same mass. - 🧠ANSWER
✔✔A few massive stars will form, live, and die before the majority of the
star's clusters even complete their protostar stage.
We do not know for certain whether the general trends we observe in
stellar birth masses also apply to brown dwarfs. But if they do, then which
of the following would be true?
Brown dwarfs would outnumber all ordinary stars.
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STATEMENT. ALL RIGHTS RESERVED
Questions and Answers | 100% Pass
Which two processes can generate energy to help a star maintain its
internal thermal pressure?
nuclear fission and supernova
nuclear fusion and supernova
nuclear fusion and nuclear fission
nuclear fusion and gravitational contraction - 🧠ANSWER ✔✔nuclear fusion
and gravitational contraction
Our Sun is considered to be a _________.
COPYRIGHT©JOSHCLAY 2025/2026. YEAR PUBLISHED 2025. COMPANY REGISTRATION NUMBER: 619652435. TERMS OF USE. PRIVACY
1
STATEMENT. ALL RIGHTS RESERVED
,low-mass star
brown dwarf
high-mass star
intermediate-mass star - 🧠ANSWER ✔✔low-mass star
Which process is required to allow a gravitationally-collapsing gas cloud to
continue to collapse?
The cloud must trap most of its thermal energy.
New dust particles must continually be made in the cloud.
The cloud must radiate much of its thermal energy.
The cloud must collide with other clouds. - 🧠ANSWER ✔✔The cloud must
radiate much of its thermal energy.
Angular momentum plays an important role in star formation. Which of the
following characteristics of a protostellar system is probably not strongly
affected by the star's angular momentum?
the existence of protostellar jets
COPYRIGHT©JOSHCLAY 2025/2026. YEAR PUBLISHED 2025. COMPANY REGISTRATION NUMBER: 619652435. TERMS OF USE. PRIVACY
2
STATEMENT. ALL RIGHTS RESERVED
,the formation of a protostellar disk
the onset of core hydrogen fusion
the strength of protostellar winds - 🧠ANSWER ✔✔the onset of core
hydrogen fusion
Generally speaking, how does the surface temperature and luminosity of a
protostar compare to the surface temperature and luminosity of the main-
sequence star it becomes?
A main-sequence star is hotter and dimmer than it was as a protostar.
A main-sequence star is cooler and dimmer than it was as a protostar.
A main-sequence star is cooler and brighter than it was as a protostar.
A main-sequence star is hotter and brighter than it was as a protostar. -
🧠ANSWER ✔✔A main-sequence star is hotter and dimmer than it was as a
protostar.
Consider a large molecular cloud that will give birth to a cluster of stars.
Which of the following would you expect to be true?
COPYRIGHT©JOSHCLAY 2025/2026. YEAR PUBLISHED 2025. COMPANY REGISTRATION NUMBER: 619652435. TERMS OF USE. PRIVACY
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STATEMENT. ALL RIGHTS RESERVED
, All the stars in the cluster will become main-sequence stars at about the
same time.
A few massive stars will form, live, and die before the majority of the star's
clusters even complete their protostar stage.
All the stars in the cluster will have approximately the same luminosity and
surface temperature.
All the stars in the cluster will be of about the same mass. - 🧠ANSWER
✔✔A few massive stars will form, live, and die before the majority of the
star's clusters even complete their protostar stage.
We do not know for certain whether the general trends we observe in
stellar birth masses also apply to brown dwarfs. But if they do, then which
of the following would be true?
Brown dwarfs would outnumber all ordinary stars.
COPYRIGHT©JOSHCLAY 2025/2026. YEAR PUBLISHED 2025. COMPANY REGISTRATION NUMBER: 619652435. TERMS OF USE. PRIVACY
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STATEMENT. ALL RIGHTS RESERVED
