Question 1

Main-sequence stars many times the mass of the Sun produce their energy by the set of nuclear reactions called the CNO cycle.

Accepted Answer

A) True 
 B)False

Question 2

Most stars generate their energy by the thermonuclear fusion of ____________________ to form ____________________.

Accepted Answer

The answer of Most stars generate their energy by the...

Question 3

in the following cartoon of the Orion constellation, the upper red supergiant star is known as Rigel and the lower right supergiant star is known as Betelgeuse.

Accepted Answer

A) True 
 B)False

Question 4

_____________ do not have enough mass to sustain nuclear fusion in its core but are more massive than planets.

Accepted Answer

The answer of _____________ do not have enough mass to...

Question 5

____________________ is the resistance of a gas to the flow of radiation.

Accepted Answer

The answer of ____________________ is the resistance of a gas...

Question 6

More massive stars have more weight to support, so these stars are more luminous.

Accepted Answer

A) True 
 B)False

Question 7

What is hydrostatic equilibrium and how is it used to explain the internal stability of a star

Accepted Answer

Hydrostatic equilibrium is the

Question 8

What is the lifetime on the main sequence of a 2-solar-mass star compared to the approximately 10-billion-year life of our Sun Pick the best answer.

Accepted Answer

A) $1.8 × 10^{11} $years 
B) $1.8 × 10^{10}$ years 
C) $1.8 × 10^8$ years 
D) $1.8 × 10^6$ years 
E) $1.8 × 10^3$ years 
A) $1.8 × 10^{11} $years 
B) $1.8 × 10^{10}$ years 
C) $1.8 × 10^8$ years 
D) $1.8 × 10^6$ years 
E) $1.8 × 10^3$ years

Question 9

Which is the correct evolutionary order

Accepted Answer

A) protostar, ZAMS, YSO 
B) protostar, YSO, ZAMS 
C) ZAMS, protostar, YSO 
D) ZAMS, YSO, protostar 
A) protostar, ZAMS, YSO 
B) protostar, YSO, ZAMS 
C) ZAMS, protostar, YSO 
D) ZAMS, YSO, protostar

Question 10

How long a star can stay on the main sequence depends upon its size.

Accepted Answer

A) True 
 B)False

Question 11

The Sun makes most of its energy by the CNO cycle.

Accepted Answer

A) True 
 B)False

Question 12

A star has crossed the birth line and thus that star is now called a ________________.

Accepted Answer

A) main-sequence star 
B) protostar 
C) YSO 
D) ZAMS 
A) main-sequence star 
B) protostar 
C) YSO 
D) ZAMS

Question 13

The thermal motions of the atoms in a gas cloud can make it collapse to form a protostar.

Accepted Answer

A) True 
 B)False

Question 14

What is the correct fraction of dust to gas in the interstellar medium

Accepted Answer

A) 1/99 
B) 10/90 
C) 50/50 
D) 90/10 
A) 1/99 
B) 10/90 
C) 50/50 
D) 90/10

Question 15

Both the CNO cycle and the proton-proton fusion chain convert hydrogen to helium using catalysts.

Accepted Answer

A) True 
 B)False

Question 16

Star may appear fainter due to the interstellar medium. This effect is known as ____________________.

Accepted Answer

A) interstellar reddening 
B) interstellar extinction 
C) interstellar absorption line 
D) interstellar dust 
A) interstellar reddening 
B) interstellar extinction 
C) interstellar absorption line 
D) interstellar dust

Question 17

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 18

Bok globules are small, dark fragments of the interstellar medium.

Accepted Answer

A) True 
 B)False

Question 19

The interstellar medium is made of ______________.

Accepted Answer

A) gas 
B) dust 
C) gas and dust 
D) None of these choices are correct. 
A) gas 
B) dust 
C) gas and dust 
D) None of these choices are correct.

Question 20

There is a main-sequence mass-luminosity relation because

Accepted Answer

A) helium fusion produces carbon. 
B) stars expand when they become giants. 
C) more massive stars support their larger weight by making more energy. 
D) the helium flash occurs in degenerate matter. 
E) all stars on the main sequence have about the same radius. 
A) helium fusion produces carbon. 
B) stars expand when they become giants. 
C) more massive stars support their larger weight by making more energy. 
D) the helium flash occurs in degenerate matter. 
E) all stars on the main sequence have about the same radius.

Main-sequence stars many times the mass of the Sun produce their energy by the set of nuclear reactions called the CNO cycle.

Most stars generate their energy by the thermonuclear fusion of to form .

in the following cartoon of the Orion constellation, the upper red supergiant star is known as Rigel and the lower right supergiant star is known as Betelgeuse.

_____________ do not have enough mass to sustain nuclear fusion in its core but are more massive than planets.

____________________ is the resistance of a gas to the flow of radiation.

More massive stars have more weight to support, so these stars are more luminous.

What is hydrostatic equilibrium and how is it used to explain the internal stability of a star

What is the lifetime on the main sequence of a 2-solar-mass star compared to the approximately 10-billion-year life of our Sun Pick the best answer.

Which is the correct evolutionary order

How long a star can stay on the main sequence depends upon its size.

The Sun makes most of its energy by the CNO cycle.

A star has crossed the birth line and thus that star is now called a ________________.

The thermal motions of the atoms in a gas cloud can make it collapse to form a protostar.

What is the correct fraction of dust to gas in the interstellar medium

Both the CNO cycle and the proton-proton fusion chain convert hydrogen to helium using catalysts.

Star may appear fainter due to the interstellar medium. This effect is known as ____________________.

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

Bok globules are small, dark fragments of the interstellar medium.

The interstellar medium is made of ______________.

There is a main-sequence mass-luminosity relation because

Here and Now

A Users Guide to the Sky

Cycles of the Sun and Moon

The Origin of Modern Astronomy

Light and Telescopes

Atoms and Spectra

The Sun

The Family of Stars

The Deaths of Stars

Neutron Stars and Black Holes

The Milky Way Galaxy

Galaxies: Normal and Active

Modern Cosmology

The Origin of the Solar System

Earth and Moon: Bases for Comparative Planetology

Mercury, Venus, and Mars

The Outer Solar System

Meteorites, Asteroids, and Comets

Astrobiology: Life on Other Worlds

Filters

Exam 9: The Formation and Structure of Stars

Main-sequence stars many times the mass of the Sun produce their energy by the set of nuclear reactions called the CNO cycle.

Most stars generate their energy by the thermonuclear fusion of ____________________ to form ____________________.

in the following cartoon of the Orion constellation, the upper red supergiant star is known as Rigel and the lower right supergiant star is known as Betelgeuse.

_____________ do not have enough mass to sustain nuclear fusion in its core but are more massive than planets.

____________________ is the resistance of a gas to the flow of radiation.

More massive stars have more weight to support, so these stars are more luminous.

What is hydrostatic equilibrium and how is it used to explain the internal stability of a star

What is the lifetime on the main sequence of a 2-solar-mass star compared to the approximately 10-billion-year life of our Sun Pick the best answer.

Which is the correct evolutionary order

How long a star can stay on the main sequence depends upon its size.

The Sun makes most of its energy by the CNO cycle.

A star has crossed the birth line and thus that star is now called a ________________.

The thermal motions of the atoms in a gas cloud can make it collapse to form a protostar.

What is the correct fraction of dust to gas in the interstellar medium

Both the CNO cycle and the proton-proton fusion chain convert hydrogen to helium using catalysts.

Star may appear fainter due to the interstellar medium. This effect is known as ____________________.

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

Bok globules are small, dark fragments of the interstellar medium.

The interstellar medium is made of ______________.

There is a main-sequence mass-luminosity relation because

Here and Now

A Users Guide to the Sky

Cycles of the Sun and Moon

The Origin of Modern Astronomy

Light and Telescopes

Atoms and Spectra

The Sun

The Family of Stars

The Deaths of Stars

Neutron Stars and Black Holes

The Milky Way Galaxy

Galaxies: Normal and Active

Modern Cosmology

The Origin of the Solar System

Earth and Moon: Bases for Comparative Planetology

Mercury, Venus, and Mars

The Outer Solar System

Meteorites, Asteroids, and Comets

Astrobiology: Life on Other Worlds

Filters

Most stars generate their energy by the thermonuclear fusion of to form .