Question 1

Why are spectra of stars different?

Accepted Answer

Spectra of stars differ primarily becaus

Question 2

All classes of binary stars yield the basic information on stellar ________.

Accepted Answer

The answer of All classes of binary stars yield the...

Question 3

Star A and star B both have an absolute magnitude of 2.0, but star A has an apparent magnitude of 5.0 and star B has an apparent magnitude of 7.0. Which statement below is correct?

Accepted Answer

A)  Star A appears brighter than star B, but star B and star A have the same intrinsic brightness. 
B)  Star B appears brighter than star A, but star B and star A have the same intrinsic brightness. 
C)  Star A and star B appear to have the same brightness, but star B is intrinsically brighter than star A. 
D)  Star A and star B appear to have the same brightness, but star A is intrinsically brighter than star B. 
E)  It is impossible to determine how bright these stars are or appear to be relative to one another, given the information above. 
A)  Star A appears brighter than star B, but star B and star A have the same intrinsic brightness. 
B)  Star B appears brighter than star A, but star B and star A have the same intrinsic brightness. 
C)  Star A and star B appear to have the same brightness, but star B is intrinsically brighter than star A. 
D)  Star A and star B appear to have the same brightness, but star A is intrinsically brighter than star B. 
E)  It is impossible to determine how bright these stars are or appear to be relative to one another, given the information above.

Question 4

If a star appears to move relative to other stars over a one-year period, this motion is due to the star's

Accepted Answer

A)  transverse motion. 
B)  radial motion. 
C)  parallax shift. 
D)  Doppler shift. 
E)  true space motion. 
A)  transverse motion. 
B)  radial motion. 
C)  parallax shift. 
D)  Doppler shift. 
E)  true space motion.

Question 5

On the main sequence, almost all stars have radii between about 0.1 and 10 times the Sun.

Accepted Answer

A) True 
 B)False

Question 6

In the H-R diagram, the bright blue-white stars that dominate the naked eye sky lie to the

Accepted Answer

A)  top left. 
B)  top right. 
C)  middle of the main sequence. 
D)  top center. 
E)  bottom left. 
A)  top left. 
B)  top right. 
C)  middle of the main sequence. 
D)  top center. 
E)  bottom left.

Question 7

At the distance of Jupiter (6 times further away from the Sun than Earth) the amount of sunlight received per square centimeter different by what factor?

Accepted Answer

A)  6 times less 
B)  12 times less 
C)  36 times less 
D)  6 times more 
E)  12 times more 
A)  6 times less 
B)  12 times less 
C)  36 times less 
D)  6 times more 
E)  12 times more

Question 8

The absolute magnitude of a star is its brightness as seen from a distance of

Accepted Answer

A)  one million kilometers. 
B)  one astronomical unit. 
C)  one light-year. 
D)  ten parsecs. 
E)  10 light-years. 
A)  one million kilometers. 
B)  one astronomical unit. 
C)  one light-year. 
D)  ten parsecs. 
E)  10 light-years.

Question 9

The nearest naked- eye star to our Sun, Alpha Centauri, is still over a parsec distant.

Accepted Answer

A) True 
 B)False

Question 10

In a binary system, the more massive stars always stay closer to the center of mass and move slower.

Accepted Answer

A) True 
 B)False

Question 11

Which of the following best describes the size and distance relationship of our Sun and the nearest star?

Accepted Answer

A)  A tennis ball here, another on the Moon 
B)  Two beach balls separated by 100 city blocks 
C)  Two grains of sand separated by 100 light-years 
D)  Two golf balls separated by 300 kilometers 
E)  Two baseballs separated by 100 yards 
A)  A tennis ball here, another on the Moon 
B)  Two beach balls separated by 100 city blocks 
C)  Two grains of sand separated by 100 light-years 
D)  Two golf balls separated by 300 kilometers 
E)  Two baseballs separated by 100 yards

Question 12

What physical property of a star does the spectral type measure?

Accepted Answer

A)  Density 
B)  Luminosity 
C)  Temperature 
D)  Mass 
E)  Composition 
A)  Density 
B)  Luminosity 
C)  Temperature 
D)  Mass 
E)  Composition

Question 13

If a star were moved 10 times farther away, its apparent magnitude would drop by five magnitudes.

Accepted Answer

A) True 
 B)False

Question 14

Star A and star B both have an apparent magnitude of 4.0, but star A has an absolute magnitude of 1.0 and star B has an absolute magnitude of 7.0. Which statement below is correct?

Accepted Answer

A)  Star A appears brighter than star B, but star B and star A have the same intrinsic brightness. 
B)  Star B appears brighter than star A, but star B and star A have the same intrinsic brightness. 
C)  Star A and star B appear to have the same brightness, but star B is intrinsically brighter than star A. 
D)  Star A and star B appear to have the same brightness, but star A is intrinsically brighter than star B. 
E)  It is impossible to determine how bright these stars are or appear to be relative to one another, given the information above. 
A)  Star A appears brighter than star B, but star B and star A have the same intrinsic brightness. 
B)  Star B appears brighter than star A, but star B and star A have the same intrinsic brightness. 
C)  Star A and star B appear to have the same brightness, but star B is intrinsically brighter than star A. 
D)  Star A and star B appear to have the same brightness, but star A is intrinsically brighter than star B. 
E)  It is impossible to determine how bright these stars are or appear to be relative to one another, given the information above.

Question 15

In a large sampling of stars, the largest group represented in the H-R diagram will be the main sequence stars. Why are they so common?

Accepted Answer

Like the Sun, they are young enough to h

Question 16

A star similar to Sirius A has a temperature of about 10,000 K, and a luminosity of around 25 times that of the Sun. Approximately what is its radius?

Accepted Answer

Using T in units of 5000 K, th

Question 17

Two red stars have surface temperatures of 3000 K, but Star A's luminosity is about 5% of the Sun's and Star B's luminosity is about 32,000 times the luminosity of the Sun. How much bigger is star B than star A?

Accepted Answer

A)  They are the same size. 
B)  Star B's radius is about 16 times larger than star A's radius. 
C)  Star B's radius is about 800 times larger than star A's radius. 
D)  Star B's radius is about 640,000 times larger than star A's radius. 
E)  This cannot be determined from the information given. 
A)  They are the same size. 
B)  Star B's radius is about 16 times larger than star A's radius. 
C)  Star B's radius is about 800 times larger than star A's radius. 
D)  Star B's radius is about 640,000 times larger than star A's radius. 
E)  This cannot be determined from the information given.

Question 18

How can a white dwarf be hotter than our Sun, yet much less luminous?

Accepted Answer

They are only about

Question 19

If a star were moved 10 times farther away, its absolute magnitude would drop five magnitudes.

Accepted Answer

A) True 
 B)False

Question 20

Star A is a main sequence star of spectral type G5 and star B is a red giant of spectral type K2. Which statement below is correct?

Accepted Answer

A)  Star A appears brighter than star B. 
B)  Star B appears brighter than star A. 
C)  Star A is hotter than star B. 
D)  Star B is hotter than star A. 
E)  None of the above can be said about these two stars. 
A)  Star A appears brighter than star B. 
B)  Star B appears brighter than star A. 
C)  Star A is hotter than star B. 
D)  Star B is hotter than star A. 
E)  None of the above can be said about these two stars.

Why are spectra of stars different?

All classes of binary stars yield the basic information on stellar ________.

Star A and star B both have an absolute magnitude of 2.0, but star A has an apparent magnitude of 5.0 and star B has an apparent magnitude of 7.0. Which statement below is correct?

If a star appears to move relative to other stars over a one-year period, this motion is due to the star's

On the main sequence, almost all stars have radii between about 0.1 and 10 times the Sun.

In the H-R diagram, the bright blue-white stars that dominate the naked eye sky lie to the

At the distance of Jupiter (6 times further away from the Sun than Earth) the amount of sunlight received per square centimeter different by what factor?

The absolute magnitude of a star is its brightness as seen from a distance of

The nearest naked- eye star to our Sun, Alpha Centauri, is still over a parsec distant.

In a binary system, the more massive stars always stay closer to the center of mass and move slower.

Which of the following best describes the size and distance relationship of our Sun and the nearest star?

What physical property of a star does the spectral type measure?

If a star were moved 10 times farther away, its apparent magnitude would drop by five magnitudes.

Star A and star B both have an apparent magnitude of 4.0, but star A has an absolute magnitude of 1.0 and star B has an absolute magnitude of 7.0. Which statement below is correct?

In a large sampling of stars, the largest group represented in the H-R diagram will be the main sequence stars. Why are they so common?

A star similar to Sirius A has a temperature of about 10,000 K, and a luminosity of around 25 times that of the Sun. Approximately what is its radius?

Two red stars have surface temperatures of 3000 K, but Star A's luminosity is about 5% of the Sun's and Star B's luminosity is about 32,000 times the luminosity of the Sun. How much bigger is star B than star A?

How can a white dwarf be hotter than our Sun, yet much less luminous?

If a star were moved 10 times farther away, its absolute magnitude would drop five magnitudes.

Star A is a main sequence star of spectral type G5 and star B is a red giant of spectral type K2. Which statement below is correct?

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Exam 9: Measuring the Stars

Why are spectra of stars different?

All classes of binary stars yield the basic information on stellar ________.

Star A and star B both have an absolute magnitude of 2.0, but star A has an apparent magnitude of 5.0 and star B has an apparent magnitude of 7.0. Which statement below is correct?

If a star appears to move relative to other stars over a one-year period, this motion is due to the star's

On the main sequence, almost all stars have radii between about 0.1 and 10 times the Sun.

In the H-R diagram, the bright blue-white stars that dominate the naked eye sky lie to the

At the distance of Jupiter (6 times further away from the Sun than Earth) the amount of sunlight received per square centimeter different by what factor?

The absolute magnitude of a star is its brightness as seen from a distance of

The nearest naked- eye star to our Sun, Alpha Centauri, is still over a parsec distant.

In a binary system, the more massive stars always stay closer to the center of mass and move slower.

Which of the following best describes the size and distance relationship of our Sun and the nearest star?

What physical property of a star does the spectral type measure?

If a star were moved 10 times farther away, its apparent magnitude would drop by five magnitudes.

Star A and star B both have an apparent magnitude of 4.0, but star A has an absolute magnitude of 1.0 and star B has an absolute magnitude of 7.0. Which statement below is correct?

In a large sampling of stars, the largest group represented in the H-R diagram will be the main sequence stars. Why are they so common?

A star similar to Sirius A has a temperature of about 10,000 K, and a luminosity of around 25 times that of the Sun. Approximately what is its radius?

Two red stars have surface temperatures of 3000 K, but Star A's luminosity is about 5% of the Sun's and Star B's luminosity is about 32,000 times the luminosity of the Sun. How much bigger is star B than star A?

How can a white dwarf be hotter than our Sun, yet much less luminous?

If a star were moved 10 times farther away, its absolute magnitude would drop five magnitudes.

Star A is a main sequence star of spectral type G5 and star B is a red giant of spectral type K2. Which statement below is correct?

The Night Sky

Light and Telescopes

The Solar System

Earth and Its Moon

The Eight Planets

Small Bodies in the Solar System

Formation of Planetary Systems

The Sun

Star Formation and Evolution

Stellar Explosions

Black Holes

The Milky Way Galaxy

Galaxies

Cosmology and the Universe

Filters