Question 1

Explain the difference between apparent visual brightness and absolute visual brightness.

Accepted Answer

Apparent visual brightness is the perceived energy we see from the Earth without consideration of distance; whereas absolute visual brightness is the energy we receive if the star was at a distance of 10 parsecs.

Question 2

One type of binary star is _______________ binary.

Accepted Answer

visual,spectroscopic,eclipsing

Question 3

Veg a i s a n A 0 main sequence star . Base d o n thi s informatio n, whic h statement is true?

Accepted Answer

A)  Vega has a surface temperature that is less than the Sun 
B)  Vega has mass that is greater than the Sun 
C)  Vega is less luminous than the Sun 
D)  Vega has mass that is less than the Sun 
E)  Vega is located near the lower right hand corner on the HR diagram 
A)  Vega has a surface temperature that is less than the Sun 
B)  Vega has mass that is greater than the Sun 
C)  Vega is less luminous than the Sun 
D)  Vega has mass that is less than the Sun 
E)  Vega is located near the lower right hand corner on the HR diagram B

Question 4

In the accompanying figure, which region represents stars that have ceased ongoing nuclear fusion? Note: (C) represents the entire main sequence while (D) and (E) represent only small parts of the main sequence.

Accepted Answer

The answer of   
In the accompanying figure, which...

Question 5

In the accompanying figure, which region represents the largest diameter stars? Note: (C) represents the entire main sequence while (D) and (E) represent only small parts of the main sequence.

Accepted Answer

The answer of   
In the accompanying figure, which...

Question 6

Absolute visual magnitude is calculated at a standard distance of ____.

Accepted Answer

A)  one light year 
B)  one parsec 
C)  10 light years 
D)  10 parsecs 
E)  100 parsecs 
A)  one light year 
B)  one parsec 
C)  10 light years 
D)  10 parsecs 
E)  100 parsecs

Question 7

Star B has an apparent visual magnitude of +5 and is at a distance of 330 pc.   What is the absolute visual magnitude of Star B?

Accepted Answer

The answer of Star B has an apparent visual magnitude...

Question 8

In the above, which figure represents stars with the longest main-sequence lifetimes? Note: (C) represents the entire main sequence while (D) and (E) represent only small parts of the main sequence.

Accepted Answer

The answer of   
In the above, which figure...

Question 9

How did astronomers discover the relationship between spectral type and mass for main sequence stars?

Accepted Answer

A)  by measuring stellar radii with very powerful optical telescopes 
B)  by measuring stellar radii with very powerful radio telescopes 
C)  by comparing stars with the same spectral type but different luminosities 
D)  by using computer models of hydrogen fusion and stellar structure 
E)  by measuring the masses and spectral types of main-sequence stars in binary systems 
A)  by measuring stellar radii with very powerful optical telescopes 
B)  by measuring stellar radii with very powerful radio telescopes 
C)  by comparing stars with the same spectral type but different luminosities 
D)  by using computer models of hydrogen fusion and stellar structure 
E)  by measuring the masses and spectral types of main-sequence stars in binary systems

Question 10

Hydrogen lines are weak in the spectra of hot O-type stars because ____.

Accepted Answer

A)  most of the hydrogen has been converted to helium 
B)  a good spectrum of these stars is difficult to obtain 
C)  these stars have no atmosphere 
D)  gravitational pressure pushes all the hydrogen lines out of the visible spectrum 
E)  most of the hydrogen is ionized to high energy levels 
A)  most of the hydrogen has been converted to helium 
B)  a good spectrum of these stars is difficult to obtain 
C)  these stars have no atmosphere 
D)  gravitational pressure pushes all the hydrogen lines out of the visible spectrum 
E)  most of the hydrogen is ionized to high energy levels

Question 11

Briefly state or explain the mass-luminosity relation for stars.

Accepted Answer

The luminosity of a star is di

Question 12

The hydrogen lines of spectral type A main sequence stars are ____.

Accepted Answer

A)  the strongest 
B)  the weakest 
C)  the most narrow 
D)  useful in determining apparent magnitude 
E)  used to estimate the luminosity of the star 
A)  the strongest 
B)  the weakest 
C)  the most narrow 
D)  useful in determining apparent magnitude 
E)  used to estimate the luminosity of the star

Question 13

The classification of stellar spectra started with the amount of hydrogen in the star's spectrum; however, now a better scheme uses the star's _____.

Accepted Answer

A)  mass 
B)  diameter 
C)  radius 
D)  temperature 
E)  luminosity 
A)  mass 
B)  diameter 
C)  radius 
D)  temperature 
E)  luminosity

Question 14

If two stars are emitting the same amount of light, the star that is farther will appear dimmer.

Accepted Answer

A) True 
 B)False

Question 15

In the accompanying figure, which region represents white dwarfs? Note: (C) represents the entire main sequence while (D) and (E) represent only small parts of the main sequence.

Accepted Answer

The answer of   
In the accompanying figure, which...

Question 16

The Sun is what spectral type?

Accepted Answer

A)  S2 
B)  G2 
C)  F2 
D)  K2 
E)  ST2 (Spectral Type 2) 
A)  S2 
B)  G2 
C)  F2 
D)  K2 
E)  ST2 (Spectral Type 2)

Question 17

The most common type of star is a(n) ____.

Accepted Answer

A)  white dwarf 
B)  lower-main-sequence star 
C)  upper-main-sequence star 
D)  giant 
E)  supergiant 
A)  white dwarf 
B)  lower-main-sequence star 
C)  upper-main-sequence star 
D)  giant 
E)  supergiant

Question 18

Determine the mass of a theorized black hole from the following information. The mass of the companion main sequence star is 6 solar masses. The observed period and semi-major axis of the binary system are 3.5 years and 5.5 AUs, respectively.

Accepted Answer

The answer of Determine the mass of a theorized black...

Question 19

Any star that is more luminous than the Sun, but has the same temperature as the Sun, is a(n) ____.

Accepted Answer

A)  pulsating star 
B)  white dwarf 
C)  zero age main sequence star 
D)  giant 
E)  brown dwarf 
A)  pulsating star 
B)  white dwarf 
C)  zero age main sequence star 
D)  giant 
E)  brown dwarf

Question 20

The least common stars are _______________ stars.

Accepted Answer

upper-main

Exam 9: The Family of Stars

Explain the difference between apparent visual brightness and absolute visual brightness.

One type of binary star is _______________ binary.

Veg a i s a n A 0 main sequence star . Base d o n thi s informatio n, whic h statement is true?

In the accompanying figure, which region represents stars that have ceased ongoing nuclear fusion? Note: (C) represents the entire main sequence while (D) and (E) represent only small parts of the main sequence.

In the accompanying figure, which region represents the largest diameter stars? Note: (C) represents the entire main sequence while (D) and (E) represent only small parts of the main sequence.

Absolute visual magnitude is calculated at a standard distance of ____.

Star B has an apparent visual magnitude of +5 and is at a distance of 330 pc. What is the absolute visual magnitude of Star B?

In the above, which figure represents stars with the longest main-sequence lifetimes? Note: (C) represents the entire main sequence while (D) and (E) represent only small parts of the main sequence.

How did astronomers discover the relationship between spectral type and mass for main sequence stars?

Hydrogen lines are weak in the spectra of hot O-type stars because ____.

Briefly state or explain the mass-luminosity relation for stars.

The hydrogen lines of spectral type A main sequence stars are ____.

The classification of stellar spectra started with the amount of hydrogen in the star's spectrum; however, now a better scheme uses the star's _____.

If two stars are emitting the same amount of light, the star that is farther will appear dimmer.

In the accompanying figure, which region represents white dwarfs? Note: (C) represents the entire main sequence while (D) and (E) represent only small parts of the main sequence.

The Sun is what spectral type?

The most common type of star is a(n) ____.

Determine the mass of a theorized black hole from the following information. The mass of the companion main sequence star is 6 solar masses. The observed period and semi-major axis of the binary system are 3.5 years and 5.5 AUs, respectively.

Any star that is more luminous than the Sun, but has the same temperature as the Sun, is a(n) ____.

The least common stars are _______________ stars.

Here and Now

A Users Guide to the Sky

Moon Phases and Eclipses

Origins of Modern Astronomy

Gravity

Light and Telescopes

Atoms and Spectra

The Sun

The Interstellar Medium

Formation and Structure of Stars

Stellar Evolution

Deaths of Stars

Neutron Stars and Black Holes

The Milky Way Galaxy

Galaxies

Supermassive Black Holes and Active Galaxies

Modern Cosmology

Origin of the Solar System and Extrasolar Planets

Earth the Active Planet

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