Astro 7n Exam 2; Questions with Complete Solutions
100% Verified
A high-luminosity star...
A. is always at a larger distance than a low-luminosity star
B. emits more light than a low-luminosity star
C. is always redder than a star with a lower luminosity
D. is at a lower temperature than a low-luminosity star
E. is always at a smaller distance than a low-luminosity star Correct answer-B
If a red giant appears the same brightness as a red main sequence star, which one is further
away?
A. the red giant
B. we cannot tell
C. it depends on the phase of the moon
D. the main sequence star
E. they are at the same distance Correct answer-A
The heaviest nuclei of all are formed...
A. during helium burning
B. as part of the p-p chain
, Astro 7n Exam 2; Questions with Complete Solutions
100% Verified
C. during the carbon burning
D. during supernova explosion
E. during all stages of stellar evolution of massive stars Correct answer-D
Fill in the blank in the following chemical reaction that occurs in the Sun: Hydrogen-2 + proton =
+ energy:
A. hydrogen-2
B. Hydrogen-1
C. Helium-3
D. Carbon-12
E. Helium - 4 Correct answer-C
Which of the following has the smallest radius?
A. type A main sequence star
B. main sequence star with surface temperature 8000K
C. type K main sequence star
D. white dwarf
E. neutron star Correct answer-E
Why does the main sequence part of a star's life end?
A. the helium in the core is exhausted
, Astro 7n Exam 2; Questions with Complete Solutions
100% Verified
B. the gravitational force is no longer large enough to balance the pressure
C. The hydrogen in the core is exhausted
D. the temperature drops so that nuclear reactions are no longer possible
E. much of the mass of the star has evaporated Correct answer-C
Which of the following will have the shortest lifetime on the main sequence?
A. main sequence star with surface temperature 20000K
B. main sequence star with surface temperature 3000K
C. main sequence star with luminosity one tenth that of the sun
D. the sun
E. main sequence star with mass 2 times the sun's Correct answer-A
Many of the brightest 100 stars viewed from Earth are not on the main sequence (even though
most stars are) because:
A. only high mass stars formed near to us in the Galaxy
B. the most luminous stars are giants and supergiants that have already finished their main
sequence lifetimes.
C. our region of the galaxy is very young
D. the main sequence is the shortest part of a star's life so stars do not spend much time there
E. our region of the galaxy is very old Correct answer-B
100% Verified
A high-luminosity star...
A. is always at a larger distance than a low-luminosity star
B. emits more light than a low-luminosity star
C. is always redder than a star with a lower luminosity
D. is at a lower temperature than a low-luminosity star
E. is always at a smaller distance than a low-luminosity star Correct answer-B
If a red giant appears the same brightness as a red main sequence star, which one is further
away?
A. the red giant
B. we cannot tell
C. it depends on the phase of the moon
D. the main sequence star
E. they are at the same distance Correct answer-A
The heaviest nuclei of all are formed...
A. during helium burning
B. as part of the p-p chain
, Astro 7n Exam 2; Questions with Complete Solutions
100% Verified
C. during the carbon burning
D. during supernova explosion
E. during all stages of stellar evolution of massive stars Correct answer-D
Fill in the blank in the following chemical reaction that occurs in the Sun: Hydrogen-2 + proton =
+ energy:
A. hydrogen-2
B. Hydrogen-1
C. Helium-3
D. Carbon-12
E. Helium - 4 Correct answer-C
Which of the following has the smallest radius?
A. type A main sequence star
B. main sequence star with surface temperature 8000K
C. type K main sequence star
D. white dwarf
E. neutron star Correct answer-E
Why does the main sequence part of a star's life end?
A. the helium in the core is exhausted
, Astro 7n Exam 2; Questions with Complete Solutions
100% Verified
B. the gravitational force is no longer large enough to balance the pressure
C. The hydrogen in the core is exhausted
D. the temperature drops so that nuclear reactions are no longer possible
E. much of the mass of the star has evaporated Correct answer-C
Which of the following will have the shortest lifetime on the main sequence?
A. main sequence star with surface temperature 20000K
B. main sequence star with surface temperature 3000K
C. main sequence star with luminosity one tenth that of the sun
D. the sun
E. main sequence star with mass 2 times the sun's Correct answer-A
Many of the brightest 100 stars viewed from Earth are not on the main sequence (even though
most stars are) because:
A. only high mass stars formed near to us in the Galaxy
B. the most luminous stars are giants and supergiants that have already finished their main
sequence lifetimes.
C. our region of the galaxy is very young
D. the main sequence is the shortest part of a star's life so stars do not spend much time there
E. our region of the galaxy is very old Correct answer-B
