Question 1

The sun creates its energy by the process of

Accepted Answer

A)  nuclear fission. 
B)  nuclear fusion. 
C)  convection. 
D)  conduction. 
E)  radiation. 
A)  nuclear fission. 
B)  nuclear fusion. 
C)  convection. 
D)  conduction. 
E)  radiation.

Question 2

Why do nuclear fusion reactions only take place in the interior of a star?

Accepted Answer

A)  The magnetic fields are strongest there. 
B)  The temperature is the hottest in the center. 
C)  The density of material is very high in the center. 
D)  Both (b) and (c) 
E)  FALSE; Nuclear fusion reactions can take place in the core and corona where temperatures are high enough. 
A)  The magnetic fields are strongest there. 
B)  The temperature is the hottest in the center. 
C)  The density of material is very high in the center. 
D)  Both (b) and (c) 
E)  FALSE; Nuclear fusion reactions can take place in the core and corona where temperatures are high enough.

Question 3

____________________ appear reddish in color due to the light emitted by the Balmer series of the hydrogen atom.

Accepted Answer

The answer of ____________________ appear reddish in color due to...

Question 4

Which of the following is NOT evidence of the existence of an interstellar medium?

Accepted Answer

A)  extinction of light from distant stars 
B)  very narrow calcium absorption lines in the spectra of O and B stars 
C)  reddening of more distant stars 
D)  dark cloud silhouetted against background stars 
E)  molecular absorption lines in the spectra of cool stars 
A)  extinction of light from distant stars 
B)  very narrow calcium absorption lines in the spectra of O and B stars 
C)  reddening of more distant stars 
D)  dark cloud silhouetted against background stars 
E)  molecular absorption lines in the spectra of cool stars

Question 5

The proton-proton chain needs high temperature because

Accepted Answer

A)  of the ground state energy of the hydrogen atom. 
B)  of the presence of helium atoms. 
C)  the protons must overcome the Coulomb barrier. 
D)  of the need for low density. 
E)  the neutrinos carry more energy away than the reaction produces. 
A)  of the ground state energy of the hydrogen atom. 
B)  of the presence of helium atoms. 
C)  the protons must overcome the Coulomb barrier. 
D)  of the need for low density. 
E)  the neutrinos carry more energy away than the reaction produces.

Question 6

Stars of spectra type K have strong Balmer lines.

Accepted Answer

A) True 
 B)False

Question 7

A star on the ____________________ generates enough energy from nuclear fusion to halt gravitational collapse.

Accepted Answer

The answer of A star on the ____________________ generates enough...

Question 8

Stars with masses greater than 1.1 solar masses use the ____________________ to convert hydrogen into helium and produce energy

Accepted Answer

The answer of Stars with masses greater than 1.1 solar...

Question 9

The solar neutrino experiments detect about twice as many neutrinos as theory predicts should be detected.

Accepted Answer

A) True 
 B)False

Question 10

How does a gas cloud become hot enough to ignite nuclear reactions?

Accepted Answer

A gas cloud, typically composed of hydro

Question 11

Why do astronomers use the molecule CO, instead of hydrogen, to map molecular clouds?

Accepted Answer

Astronomers use the molecule carbon mono

Question 12

What characteristic of a star primarily determines its location on the main sequence?

Accepted Answer

A)  age 
B)  distance from the galactic center 
C)  mass 
D)  space motion 
E)  radius 
A)  age 
B)  distance from the galactic center 
C)  mass 
D)  space motion 
E)  radius

Question 13

The extinction of starlight due to the interstellar medium
I. is the greatest in the ultraviolet.
II. is the greatest in the infrared.
III. is caused by ionized hydrogen.
IV. is caused by dust particles.

Accepted Answer

A)  I,III 
B)  II III 
C)  I, IV 
D)  II IV 
E)  only IV 
A)  I,III 
B)  II III 
C)  I, IV 
D)  II IV 
E)  only IV

Question 14

How does the method of energy generation inside main sequence stars affect their internal structure?

Accepted Answer

The answer of How does the method of energy generation...

Question 15

Molecular clouds are mapped using CO instead of hydrogen because CO is much more abundant than hydrogen in molecular clouds.

Accepted Answer

A) True 
 B)False

Question 16

A jet has an angular length of 10 seconds of arc and flows from a star at a distance of 2,000 pc. How far does this jet extend away from the star?

Accepted Answer

A)  20,000 pc 
B)  20,000 AU 
C)  20, 000 ly 
D)  20,000 miles 
E)  20,000 km 
A)  20,000 pc 
B)  20,000 AU 
C)  20, 000 ly 
D)  20,000 miles 
E)  20,000 km

Question 17

Molecular clouds can be observed

Accepted Answer

A)  using infrared telescopes to detect ionized gas in the clouds. 
B)  using x-ray telescope to observe the x-ray radiation from the molecules in the cloud. 
C)  using radio telescopes to observe the CO emission from the clouds. 
D)  by looking for blue wispy regions near star clusters. 
E)  by looking for the 21-cm radiation from hydrogen. 
A)  using infrared telescopes to detect ionized gas in the clouds. 
B)  using x-ray telescope to observe the x-ray radiation from the molecules in the cloud. 
C)  using radio telescopes to observe the CO emission from the clouds. 
D)  by looking for blue wispy regions near star clusters. 
E)  by looking for the 21-cm radiation from hydrogen.

Question 18

The Orion region contains young main sequence stars and an emission nebula, but the original molecular cloud they formed out of has been dispersed.

Accepted Answer

A) True 
 B)False

Question 19

Explain what keeps the nuclear reactions in a star under control.

Accepted Answer

The nuclear reactions in a star are kept

Question 20

The carbon-nitrogen-oxygen cycle

Accepted Answer

A)  operates at a slightly lower temperature than the proton-proton chain. 
B)  is most efficient in star less massive than the sun. 
C)  occurs when carbon and oxygen combine to form nitrogen, which produces energy. 
D)  produces the energy responsible for bipolar flows. 
E)  combines four hydrogen nuclei to form one helium nucleus, which produces energy. 
A)  operates at a slightly lower temperature than the proton-proton chain. 
B)  is most efficient in star less massive than the sun. 
C)  occurs when carbon and oxygen combine to form nitrogen, which produces energy. 
D)  produces the energy responsible for bipolar flows. 
E)  combines four hydrogen nuclei to form one helium nucleus, which produces energy.

The sun creates its energy by the process of

Why do nuclear fusion reactions only take place in the interior of a star?

____________________ appear reddish in color due to the light emitted by the Balmer series of the hydrogen atom.

Which of the following is NOT evidence of the existence of an interstellar medium?

The proton-proton chain needs high temperature because

Stars of spectra type K have strong Balmer lines.

A star on the ____________________ generates enough energy from nuclear fusion to halt gravitational collapse.

Stars with masses greater than 1.1 solar masses use the ____________________ to convert hydrogen into helium and produce energy

The solar neutrino experiments detect about twice as many neutrinos as theory predicts should be detected.

How does a gas cloud become hot enough to ignite nuclear reactions?

Why do astronomers use the molecule CO, instead of hydrogen, to map molecular clouds?

What characteristic of a star primarily determines its location on the main sequence?

The extinction of starlight due to the interstellar medium I. is the greatest in the ultraviolet. II. is the greatest in the infrared. III. is caused by ionized hydrogen. IV. is caused by dust particles.

How does the method of energy generation inside main sequence stars affect their internal structure?

Molecular clouds are mapped using CO instead of hydrogen because CO is much more abundant than hydrogen in molecular clouds.

A jet has an angular length of 10 seconds of arc and flows from a star at a distance of 2,000 pc. How far does this jet extend away from the star?

Molecular clouds can be observed

The Orion region contains young main sequence stars and an emission nebula, but the original molecular cloud they formed out of has been dispersed.

Explain what keeps the nuclear reactions in a star under control.

The carbon-nitrogen-oxygen cycle

Here and Now

Users Guide to the Sky: Patterns and Cycles

The Origin of Modern Astronomy

Light and Telescopes

Sun Light and Sun Atoms

The Terrestrial Planets

The Outer Solar System

Origins of the Solar System and Extrasolar Planets

The Family of Stars

The Deaths of Stars

The Milky Way Galaxy

Galaxies: Normal and Active

Modern Cosmology

Life on Other Worlds

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Exam 10: Structure and Formation of Stars

The sun creates its energy by the process of

Why do nuclear fusion reactions only take place in the interior of a star?

____________________ appear reddish in color due to the light emitted by the Balmer series of the hydrogen atom.

Which of the following is NOT evidence of the existence of an interstellar medium?

The proton-proton chain needs high temperature because

Stars of spectra type K have strong Balmer lines.

A star on the ____________________ generates enough energy from nuclear fusion to halt gravitational collapse.

Stars with masses greater than 1.1 solar masses use the ____________________ to convert hydrogen into helium and produce energy

The solar neutrino experiments detect about twice as many neutrinos as theory predicts should be detected.

How does a gas cloud become hot enough to ignite nuclear reactions?

Why do astronomers use the molecule CO, instead of hydrogen, to map molecular clouds?

What characteristic of a star primarily determines its location on the main sequence?

The extinction of starlight due to the interstellar medium I. is the greatest in the ultraviolet. II. is the greatest in the infrared. III. is caused by ionized hydrogen. IV. is caused by dust particles.

How does the method of energy generation inside main sequence stars affect their internal structure?

Molecular clouds are mapped using CO instead of hydrogen because CO is much more abundant than hydrogen in molecular clouds.

A jet has an angular length of 10 seconds of arc and flows from a star at a distance of 2,000 pc. How far does this jet extend away from the star?

Molecular clouds can be observed

The Orion region contains young main sequence stars and an emission nebula, but the original molecular cloud they formed out of has been dispersed.

Explain what keeps the nuclear reactions in a star under control.

The carbon-nitrogen-oxygen cycle

Here and Now

Users Guide to the Sky: Patterns and Cycles

The Origin of Modern Astronomy

Light and Telescopes

Sun Light and Sun Atoms

The Terrestrial Planets

The Outer Solar System

Origins of the Solar System and Extrasolar Planets

The Family of Stars

The Deaths of Stars

The Milky Way Galaxy

Galaxies: Normal and Active

Modern Cosmology

Life on Other Worlds

Filters