Question 1

The more distant a star,the smaller its parallax.

Accepted Answer

A) True 
 B)False

Question 2

A star with a parallax angle of 1/20 arcsecond is

Accepted Answer

A) 20 light-years away. 
B) 1/20 parsec away. 
C) 20 parsecs away. 
D) 10 parsecs away. 
A) 20 light-years away. 
B) 1/20 parsec away. 
C) 20 parsecs away. 
D) 10 parsecs away.

Question 3

How is the lifetime of a star related to its mass?

Accepted Answer

A) More massive stars live slightly shorter lives than less massive stars. 
B) More massive stars live much longer lives than less massive stars. 
C) More massive stars live much shorter lives than less massive stars. 
D) More massive stars live slightly longer lives than less massive stars. 
A) More massive stars live slightly shorter lives than less massive stars. 
B) More massive stars live much longer lives than less massive stars. 
C) More massive stars live much shorter lives than less massive stars. 
D) More massive stars live slightly longer lives than less massive stars.

Question 4

Why do astronomers often measure the visible-light apparent brightness instead of the total apparent brightness of a star?

Accepted Answer

A) All stars put out most of their light in the visible range of the spectrum. 
B) In order to measure the total apparent brightness of a star,you must measure its brightness in all wavelengths,and this is difficult to do.The only wavelengths you can measure from the surface of Earth are visible and radio wavelengths. 
C) Most stars do not put out light in other ranges of the spectrum. 
D) They are identical for most stars. 
E) Astronomers are lazy. 
A) All stars put out most of their light in the visible range of the spectrum. 
B) In order to measure the total apparent brightness of a star,you must measure its brightness in all wavelengths,and this is difficult to do.The only wavelengths you can measure from the surface of Earth are visible and radio wavelengths. 
C) Most stars do not put out light in other ranges of the spectrum. 
D) They are identical for most stars. 
E) Astronomers are lazy.

Question 5

Each choice below lists a spectral type and luminosity class for a star.Which one is a red supergiant?

Accepted Answer

A) spectral type M1,luminosity class V 
B) spectral type O9,luminosity class I 
C) spectral type G2,luminosity class V 
D) spectral type M2,luminosity class I 
A) spectral type M1,luminosity class V 
B) spectral type O9,luminosity class I 
C) spectral type G2,luminosity class V 
D) spectral type M2,luminosity class I

Question 6

On an H-R diagram,stellar masses

Accepted Answer

A) can be determined for main-sequence stars but not for other types of stars. 
B) are greatest in the lower left and least in the upper right. 
C) decrease from upper left to lower right. 
D) are impossible to determine. 
A) can be determined for main-sequence stars but not for other types of stars. 
B) are greatest in the lower left and least in the upper right. 
C) decrease from upper left to lower right. 
D) are impossible to determine.

Question 7

Which of the following terms is given to a pair of stars that we can determine are orbiting each other only by measuring their periodic Doppler shifts?

Accepted Answer

A) visual binary 
B) eclipsing binary 
C) spectroscopic binary 
D) double star 
E) none of the above 
A) visual binary 
B) eclipsing binary 
C) spectroscopic binary 
D) double star 
E) none of the above

Question 8

Which of the following statements about a globular cluster is true?

Accepted Answer

A) All stars in the cluster are approximately at the same stage in evolution. 
B) Most of the stars in the cluster are younger than 10 billion years old. 
C) Most stars in the cluster are yellow or reddish in color. 
D) All stars in the cluster have approximately the same mass. 
E) There is an approximately equal number of all types of stars in the cluster. 
A) All stars in the cluster are approximately at the same stage in evolution. 
B) Most of the stars in the cluster are younger than 10 billion years old. 
C) Most stars in the cluster are yellow or reddish in color. 
D) All stars in the cluster have approximately the same mass. 
E) There is an approximately equal number of all types of stars in the cluster.

Question 9

Which of the following correctly states the luminosity-distance formula?

Accepted Answer

A) luminosity =   
B) apparent brightness =   
C) apparent brightness = luminosity × 4π × (distance)² 
D) distance =   
A) luminosity =   
B) apparent brightness =   
C) apparent brightness = luminosity × 4π × (distance)² 
D) distance =

Question 10

Refer to the choices in the table for the following questions.
  
-Which star is emitting the most ultraviolet light per unit area?

Accepted Answer

The answer of Refer to the choices in the table...

Question 11

The following questions refer to the sketch of the H-R diagram below.Please choose the best answer in each case,i.e. ,choice (a)refers to the entire main sequence,while (c)and (d)refer to only small parts of the main sequence.If choice (c)or (d)offers a better answer to a particular question than (a),use the best choice.You may use the same choice more than once.
  
-Which group represents stars burning hydrogen in their cores?

Accepted Answer

The answer of The following questions refer to the sketch...

Question 12

If Star A is closer to us than Star B,then Star A's parallax angle is

Accepted Answer

A) smaller than that of Star B. 
B) larger than that of Star B. 
C) hotter than that of Star B. 
D) fewer parsecs than that of Star B. 
A) smaller than that of Star B. 
B) larger than that of Star B. 
C) hotter than that of Star B. 
D) fewer parsecs than that of Star B.

Question 13

Earth is about 150 million km from the Sun,and the apparent brightness of the Sun in our sky is about 1,300 watts per square meter.Determine the apparent brightness we would measure for the Sun if we were located five times Earth's distance from the Sun.

Accepted Answer

The Sun would appear 1/25 time

Question 14

The following questions refer to the sketch of the H-R diagram below.Please choose the best answer in each case,i.e. ,choice (a)refers to the entire main sequence,while (c)and (d)refer to only small parts of the main sequence.If choice (c)or (d)offers a better answer to a particular question than (a),use the best choice.You may use the same choice more than once.
  
-Which group represents stars that are extremely bright and emit most of their radiation as ultraviolet light?

Accepted Answer

The answer of The following questions refer to the sketch...

Question 15

Cluster ages can be determined from

Accepted Answer

A) main sequence fitting. 
B) main sequence turnoff. 
C) pulsating variable stars. 
D) spectroscopic binaries. 
E) visual binaries. 
A) main sequence fitting. 
B) main sequence turnoff. 
C) pulsating variable stars. 
D) spectroscopic binaries. 
E) visual binaries.

Question 16

The following questions refer to the sketch of the H-R diagram below.Please choose the best answer in each case,i.e. ,choice (a)refers to the entire main sequence,while (c)and (d)refer to only small parts of the main sequence.If choice (c)or (d)offers a better answer to a particular question than (a),use the best choice.You may use the same choice more than once.
  
-Which group includes the Sun?

Accepted Answer

The answer of The following questions refer to the sketch...

Question 17

Which of the following best describes the axes of a Hertzsprung-Russell (H-R)diagram?

Accepted Answer

A) surface temperature on the horizontal axis and luminosity on the vertical axis 
B) mass on the horizontal axis and luminosity on the vertical axis 
C) surface temperature on the horizontal axis and radius on the vertical axis 
D) mass on the horizontal axis and stellar age on the vertical axis 
E) interior temperature on the horizontal axis and mass on the vertical axis 
A) surface temperature on the horizontal axis and luminosity on the vertical axis 
B) mass on the horizontal axis and luminosity on the vertical axis 
C) surface temperature on the horizontal axis and radius on the vertical axis 
D) mass on the horizontal axis and stellar age on the vertical axis 
E) interior temperature on the horizontal axis and mass on the vertical axis

Question 18

The following questions refer to the sketch of the H-R diagram below.Please choose the best answer in each case,i.e. ,choice (a)refers to the entire main sequence,while (c)and (d)refer to only small parts of the main sequence.If choice (c)or (d)offers a better answer to a particular question than (a),use the best choice.You may use the same choice more than once.
  
-Which group represents hydrogen-burning stars with the longest lifetimes?

Accepted Answer

The answer of The following questions refer to the sketch...

Question 19

Which of the following persons used the ideas of quantum mechanics to describe why the spectral classification scheme is in order of decreasing temperature?

Accepted Answer

A) Annie Jump Cannon 
B) Williamina Fleming 
C) Cecilia Payne-Gaposchkin 
D) Henry Draper 
E) Edward Pickering 
A) Annie Jump Cannon 
B) Williamina Fleming 
C) Cecilia Payne-Gaposchkin 
D) Henry Draper 
E) Edward Pickering

Question 20

What are the standard units for apparent brightness?

Accepted Answer

A) watts 
B) joules 
C) Newtons 
D) watts per second 
E) watts per square meter 
A) watts 
B) joules 
C) Newtons 
D) watts per second 
E) watts per square meter

Exam 15: Surveying the Stars

The more distant a star,the smaller its parallax.

A star with a parallax angle of 1/20 arcsecond is

How is the lifetime of a star related to its mass?

Why do astronomers often measure the visible-light apparent brightness instead of the total apparent brightness of a star?

Each choice below lists a spectral type and luminosity class for a star.Which one is a red supergiant?

On an H-R diagram,stellar masses

Which of the following terms is given to a pair of stars that we can determine are orbiting each other only by measuring their periodic Doppler shifts?

Which of the following statements about a globular cluster is true?

Which of the following correctly states the luminosity-distance formula?

Refer to the choices in the table for the following questions. -Which star is emitting the most ultraviolet light per unit area?

If Star A is closer to us than Star B,then Star A's parallax angle is

Earth is about 150 million km from the Sun,and the apparent brightness of the Sun in our sky is about 1,300 watts per square meter.Determine the apparent brightness we would measure for the Sun if we were located five times Earth's distance from the Sun.

Cluster ages can be determined from

Which of the following best describes the axes of a Hertzsprung-Russell (H-R)diagram?

Which of the following persons used the ideas of quantum mechanics to describe why the spectral classification scheme is in order of decreasing temperature?

What are the standard units for apparent brightness?

A Modern View of the Universe

Discovering the Universe for Yourself

The Science of Astronomy

Making Sense of the Universe: Understanding Motion, Energy, and Gravity

Light and Matter: Reading Messages from the Cosmos

Telescopes: Portals of Discovery

Our Planetary System

Formation of the Solar System

Planetary Geology: Earth and the Other Terrestrial Worlds

Planetary Atmospheres: Earth and the Other Terrestrial Worlds

Jovian Planet Systems

Asteroids, Comets, and Dwarf Planets: Their Nature, Orbits, and Impacts

Other Planetary Systems: The New Science of Distant Worlds

Our Star

Star Birth

Star Stuff

The Bizarre Stellar Graveyard

Our Galaxy

Galaxies and the Foundations of Modern Cosmology

Galaxy Evolution

The Birth of the Universe

Dark Matter, Dark Energy, and the Fate of the Universe

Life in the Universe

Celestial Timekeeping and Navigation

Space and Time

Spacetime and Gravity

Building Blocks of the Universe

Filters