What is the spectral sequence in order of increasing temperature?
MKFAGBO
BAFGKMO
MKGFABO
ABFMKGO
Which of the following can we use to determine the surface temperature of a star?
determining if the star has a companion star
studying its line absorption spectrum
measuring the star’s distance
measuring the star’s parallax
The table lists the spectral types for each of four stars. Which star in this table would have the lowest surface temperature?
α For
ο Cet
γ Tri
ξ Per
The table lists the spectral types for each of four stars. Which star in this table would have the highest surface temperature?
a
What properties of a star determine its luminosity?
distance and diameter
temperature and distance
temperature and diameter
apparent magnitude and temperature
How do we know that giant stars are larger in diameter than the Sun?
They are more luminous but have about the same temperature
They are less luminous but have about the same temperature
They are hotter but have about the same luminosity
They are cooler but have about the same luminosity
Sirius A and B are two stars at the same distance from the Earth. In this binary system, Sirius A is much brighter but Sirius B is much hotter. From this information, what can you conclude about the two stars?
Sirius B must be much smaller than Sirius A
Sirius B must be much larger than Sirius A
Sirius B must be much more massive than Sirius A
Sirius B must be much less massive than Sirius A
In a Hertzsprung-Russell diagram, where are the stars with the smallest radius found?
in the upper left corner
in the upper right corner
in the lower left corner
in the lower right corner
In a Hertzsprung-Russell diagram, where are 90 percent of all the stars found?
in the giant region
in the supergiant region
on the dwarf sequence
on the main sequence
The star named Sheat is of spectral type M2 and luminosity class II. Based on this information, how does Sheat compare to the Sun?
Sheat is cooler and larger than the Sun
Sheat is cooler and smaller than the Sun
Sheat is hotter and more luminous than the Sun
Sheat is hotter and larger than the Sun
The star named Circini has the spectral type and luminosity class of O 8.5 V. Based on this information, how does Circini compare to the Sun?
Circini is cooler and larger than the Sun
Circini is cooler and smaller than the Sun
Circini is hotter and more luminous than the Sun
Circini is hotter and less luminous than the Sun
Where are red giant stars found in the Hertzsprung-Russell diagram?
above the main sequence
below the main sequence
on the lower main sequence
on the upper main sequence
Which star in the table is the closest to Earth?
δ Cen
HR 4758
HD 39801
9 CMa
Which star in the table has the highest surface temperature?
Which star in the table has the largest diameter?
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