Question 1

Some young star clusters contain large numbers of T Tauri stars.

Accepted Answer

A) True 
 B)False

Question 2

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

Accepted Answer

A) age 
B) distance from the galactic centre 
C) mass 
D) radius 
A) age 
B) distance from the galactic centre 
C) mass 
D) radius

Question 3

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

Accepted Answer

Emission n

Question 4

Why is there a main sequence mass-luminosity relation?

Accepted Answer

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

Question 5

Under what conditions might interstellar gas clouds collapse to form stars?

Accepted Answer

A) if they encounter a shock wave 
B) if they have very high temperatures 
C) if they rotate rapidly 
D) if they are located near main-sequence spectral type K and M stars 
A) if they encounter a shock wave 
B) if they have very high temperatures 
C) if they rotate rapidly 
D) if they are located near main-sequence spectral type K and M stars

Question 6

Why does the main sequence have a limit at the lower end?

Accepted Answer

A) Low mass stars form from the interstellar medium very rarely. 
B) Low mass objects are composed primarily of solids, not gases. 
C) The lower limit represents a star with zero radius. 
D) A minimum temperature is required for hydrogen nuclear fusion to take place. 
A) Low mass stars form from the interstellar medium very rarely. 
B) Low mass objects are composed primarily of solids, not gases. 
C) The lower limit represents a star with zero radius. 
D) A minimum temperature is required for hydrogen nuclear fusion to take place.

Question 7

-Refer to the H-R diagram.Which of the points represents a star in which the proton-proton chain is occurring?

Accepted Answer

A) 1 
B) 2 
C) 3 
D) 4 
A) 1 
B) 2 
C) 3 
D) 4

Question 8

Why is the presence of massive stars in the Orion Nebula an indication that star formation is currently occurring?

Accepted Answer

A) The Orion Nebula contains large amounts of gas and dust. 
B) Massive stars have short lives, so they must have formed recently. 
C) Massive stars trigger star formation in nearby gas clouds. 
D) The Orion Nebula contains large numbers of brown dwarfs and supernova remnants. 
A) The Orion Nebula contains large amounts of gas and dust. 
B) Massive stars have short lives, so they must have formed recently. 
C) Massive stars trigger star formation in nearby gas clouds. 
D) The Orion Nebula contains large numbers of brown dwarfs and supernova remnants.

Question 9

Due to the dust in the interstellar medium,how will a distant star will appear to an observer on Earth?

Accepted Answer

A) brighter and cooler than it really is 
B) brighter and hotter than it really is 
C) fainter and cooler than it really is 
D) fainter and hotter than it really is 
A) brighter and cooler than it really is 
B) brighter and hotter than it really is 
C) fainter and cooler than it really is 
D) fainter and hotter than it really is

Question 10

What observations confirm the existence of protostars?

Accepted Answer

There are several observations that conf

Question 11

What happens to light as it passes through dark nebulae?

Accepted Answer

A) transmission 
B) emission 
C) reflection 
D) absorption 
A) transmission 
B) emission 
C) reflection 
D) absorption

Question 12

How did observations at the Sudbury Neutrino Observatory solve the solar neutrino problem?

Accepted Answer

A) They showed that the "missing neutrinos" had changed into a different type. 
B) They showed that other experiments had mis-counted the number of solar neutrinos. 
C) They showed that models for the number of neutrinos produced by the Sun were wrong. 
D) They showed that neutrinos were not escaping from the core of the Sun. 
A) They showed that the "missing neutrinos" had changed into a different type. 
B) They showed that other experiments had mis-counted the number of solar neutrinos. 
C) They showed that models for the number of neutrinos produced by the Sun were wrong. 
D) They showed that neutrinos were not escaping from the core of the Sun.

Question 13

Why are massive stars more luminous than low mass stars? That is,why is there a mass-luminosity relation?

Accepted Answer

The answer of Why are massive stars more luminous than...

Question 14

T Tauri stars are believed to be young,high mass main-sequence stars.

Accepted Answer

A) True 
 B)False

Question 15

Which of the following factors explain why infrared telescopes are used to observe protostars?

Accepted Answer

A) density and composition 
B) density and the presence of dust 
C) temperature and the presence of dust 
D) temperature and luminosity 
A) density and composition 
B) density and the presence of dust 
C) temperature and the presence of dust 
D) temperature and luminosity

Question 16

What concept explains why both fusion and fission release energy?

Accepted Answer

A) proton-proton chain energy 
B) Coulomb barrier energy 
C) strong force energy 
D) nuclear binding energy 
A) proton-proton chain energy 
B) Coulomb barrier energy 
C) strong force energy 
D) nuclear binding energy

Question 17

Which of the following is considered to be the best explanation for the missing solar neutrinos?

Accepted Answer

A) The Sun is fusing helium but not hydrogen. 
B) Nuclear reactions do not produce neutrinos as fast as theory predicts. 
C) The Sun may contain matter we haven't yet identified. 
D) Neutrinos may oscillate between three different flavours. 
A) The Sun is fusing helium but not hydrogen. 
B) Nuclear reactions do not produce neutrinos as fast as theory predicts. 
C) The Sun may contain matter we haven't yet identified. 
D) Neutrinos may oscillate between three different flavours.

Question 18

What must occur for an object to be considered a main-sequence star?

Accepted Answer

A) Hydrostatic equilibrium ends. 
B) Nuclear fusion reactions in the core begin. 
C) Helium flash occurs in the core. 
D) Gravitational contraction begins. 
A) Hydrostatic equilibrium ends. 
B) Nuclear fusion reactions in the core begin. 
C) Helium flash occurs in the core. 
D) Gravitational contraction begins.

Question 19

What is the source of the pink glow within the Great Nebula in Orion?

Accepted Answer

A) a Herbig-Haro object 
B) a reflection nebula made of dust 
C) young low-mass stars 
D) an emission nebula made of gas 
A) a Herbig-Haro object 
B) a reflection nebula made of dust 
C) young low-mass stars 
D) an emission nebula made of gas

Question 20

How do measurements of neutrinos from the Sun pose a problem for modern astronomy?

Accepted Answer

The measurements of neutrinos from the S

Some young star clusters contain large numbers of T Tauri stars.

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

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

Why is there a main sequence mass-luminosity relation?

Under what conditions might interstellar gas clouds collapse to form stars?

Why does the main sequence have a limit at the lower end?

-Refer to the H-R diagram.Which of the points represents a star in which the proton-proton chain is occurring?

Why is the presence of massive stars in the Orion Nebula an indication that star formation is currently occurring?

Due to the dust in the interstellar medium,how will a distant star will appear to an observer on Earth?

What observations confirm the existence of protostars?

What happens to light as it passes through dark nebulae?

How did observations at the Sudbury Neutrino Observatory solve the solar neutrino problem?

Why are massive stars more luminous than low mass stars? That is,why is there a mass-luminosity relation?

T Tauri stars are believed to be young,high mass main-sequence stars.

Which of the following factors explain why infrared telescopes are used to observe protostars?

What concept explains why both fusion and fission release energy?

Which of the following is considered to be the best explanation for the missing solar neutrinos?

What must occur for an object to be considered a main-sequence star?

What is the source of the pink glow within the Great Nebula in Orion?

How do measurements of neutrinos from the Sun pose a problem for modern astronomy?

The Scale of the Cosmos

User's Guide to the Sky

The Origin of Modern Astronomy

Astronomical Telescopes and Instruments

Sun Light and Sun Atoms

The Family of Stars

The Deaths of Stars

The Milky Way Galaxy

Galaxies

Cosmology in the 21st Century

The Origin of the Solar System

Comparative Planetology of the Terrestrial Planets

Comparative Planetology of the Jovian Planets

Life on Other Worlds

Filters

Exam 7: The Structure and Formation of Stars

Some young star clusters contain large numbers of T Tauri stars.

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

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

Why is there a main sequence mass-luminosity relation?

Under what conditions might interstellar gas clouds collapse to form stars?

Why does the main sequence have a limit at the lower end?

-Refer to the H-R diagram.Which of the points represents a star in which the proton-proton chain is occurring?

Why is the presence of massive stars in the Orion Nebula an indication that star formation is currently occurring?

Due to the dust in the interstellar medium,how will a distant star will appear to an observer on Earth?

What observations confirm the existence of protostars?

What happens to light as it passes through dark nebulae?

How did observations at the Sudbury Neutrino Observatory solve the solar neutrino problem?

Why are massive stars more luminous than low mass stars? That is,why is there a mass-luminosity relation?

T Tauri stars are believed to be young,high mass main-sequence stars.

Which of the following factors explain why infrared telescopes are used to observe protostars?

What concept explains why both fusion and fission release energy?

Which of the following is considered to be the best explanation for the missing solar neutrinos?

What must occur for an object to be considered a main-sequence star?

What is the source of the pink glow within the Great Nebula in Orion?

How do measurements of neutrinos from the Sun pose a problem for modern astronomy?

The Scale of the Cosmos

User's Guide to the Sky

The Origin of Modern Astronomy

Astronomical Telescopes and Instruments

Sun Light and Sun Atoms

The Family of Stars

The Deaths of Stars

The Milky Way Galaxy

Galaxies

Cosmology in the 21st Century

The Origin of the Solar System

Comparative Planetology of the Terrestrial Planets

Comparative Planetology of the Jovian Planets

Life on Other Worlds

Filters