Question 1

It is theorized that a pulsar only emits X-rays and visible light during its early history. What do you suppose is the basis of this theory?

Accepted Answer

A) As the pulsar's energy dissipates, the frequency of the energy it emits drops. 
B) X-rays are likely the result of radioactive decay, which only can occur in a pulsar's early history 
C) X-rays and visible light are both part of the electromagnetic spectrum. 
D) The pulsars high rate of spin produces a magnetic field that, over time, slows the pulsar down. 
A) As the pulsar's energy dissipates, the frequency of the energy it emits drops. 
B) X-rays are likely the result of radioactive decay, which only can occur in a pulsar's early history 
C) X-rays and visible light are both part of the electromagnetic spectrum. 
D) The pulsars high rate of spin produces a magnetic field that, over time, slows the pulsar down.

Question 2

The Milky Way is

Accepted Answer

A) a spiral galaxy. 
B) an elliptical galaxy. 
C) an irregular galaxy. 
D) a galaxy in the making. 
E) the remains of a galaxy that has run its life course. 
A) a spiral galaxy. 
B) an elliptical galaxy. 
C) an irregular galaxy. 
D) a galaxy in the making. 
E) the remains of a galaxy that has run its life course.

Question 3

A Starburst galaxy has this name because of its

Accepted Answer

A) high rate of star formation. 
B) high rate of supernovae. 
C) large number of pulsars. 
D) large number of neutron stars. 
A) high rate of star formation. 
B) high rate of supernovae. 
C) large number of pulsars. 
D) large number of neutron stars.

Question 4

What is the upper limit of stars the unaided eye can discern on a moonless night in a rural area?

Accepted Answer

A) About 3,000 
B) About 30,000 
C) About 300,000 
D) About 3,000,000 
A) About 3,000 
B) About 30,000 
C) About 300,000 
D) About 3,000,000

Question 5

What prevents stars greater than about 100 times the Sun's mass from existing?

Accepted Answer

A) The rate of thermal expansion would overcome gravitational attraction leading to explosion 
B) The gravitational attraction would overcome the rate of thermal expansion leading to a black hole 
C) Fusion cannot take place at these higher mass levels 
D) The gaseous material of the universe is too widely dispersed to allow for the formation of stars of this mass 
A) The rate of thermal expansion would overcome gravitational attraction leading to explosion 
B) The gravitational attraction would overcome the rate of thermal expansion leading to a black hole 
C) Fusion cannot take place at these higher mass levels 
D) The gaseous material of the universe is too widely dispersed to allow for the formation of stars of this mass

Question 6

Quasars are

Accepted Answer

A) ancient, extremely high energy galaxies believed to have formed in the early universe. 
B) a conglomeration of pulsars within a galaxy. 
C) a conglomeration of spiral galaxies. 
D) white dwarfs that have undergone final collapse. 
A) ancient, extremely high energy galaxies believed to have formed in the early universe. 
B) a conglomeration of pulsars within a galaxy. 
C) a conglomeration of spiral galaxies. 
D) white dwarfs that have undergone final collapse.

Question 7

Galaxies are aggregations of stars, stellar dust, and gas. Their masses

Accepted Answer

A) are all about the same, which is huge. 
B) vary greatly from one galaxy to the next. 
C) are small compared to blue supergiant stars. 
D) depend on the rate of pulsar emissions within them. 
A) are all about the same, which is huge. 
B) vary greatly from one galaxy to the next. 
C) are small compared to blue supergiant stars. 
D) depend on the rate of pulsar emissions within them.

Question 8

Which star will emit the shortest wavelength of its peak frequency?

Accepted Answer

A) A blue star 
B) A yellow star 
C) A red star 
D) A green star 
A) A blue star 
B) A yellow star 
C) A red star 
D) A green star

Question 9

Most of the stars in colliding galaxies

Accepted Answer

A) do not make contact with one another. 
B) coalesce into larger stars. 
C) exchange amounts of material in proportion to their masses. 
D) end up as binaries. 
E) undergo accelerated collapse. 
A) do not make contact with one another. 
B) coalesce into larger stars. 
C) exchange amounts of material in proportion to their masses. 
D) end up as binaries. 
E) undergo accelerated collapse.

Question 10

Why does a star's color corresponds to its temperature?

Accepted Answer

A) Higher temperature means more energetic light, which is seen as higher frequencies. 
B) Because of the light shifts that take place when star light interacts with the Earth's atmosphere 
C) Because the core temperature averages with the surface temperature to create an overall color 
D) Because the ultraviolet output of a star directly modifies the visible light spectrum the star is emitting 
A) Higher temperature means more energetic light, which is seen as higher frequencies. 
B) Because of the light shifts that take place when star light interacts with the Earth's atmosphere 
C) Because the core temperature averages with the surface temperature to create an overall color 
D) Because the ultraviolet output of a star directly modifies the visible light spectrum the star is emitting

Question 11

The temperature of a star is evidenced by its

Accepted Answer

A) brightness. 
B) color. 
C) angular momentum. 
D) distance. 
E) rate of burning. 
A) brightness. 
B) color. 
C) angular momentum. 
D) distance. 
E) rate of burning.

Question 12

The Milky Way galaxy is

Accepted Answer

A) in the process of colliding with the Magellanic Cloud galaxies. 
B) where Earth resides. 
C) a spiral galaxy. 
D) All of the above 
A) in the process of colliding with the Magellanic Cloud galaxies. 
B) where Earth resides. 
C) a spiral galaxy. 
D) All of the above

Question 13

Compared to most stellar objects, quasars are more

Accepted Answer

A) distant. 
B) energetic. 
C) puzzling. 
D) all of these 
E) none of these 
A) distant. 
B) energetic. 
C) puzzling. 
D) all of these 
E) none of these

Question 14

What determines if a star becomes a white dwarf, a neutron star, or a black hole?

Accepted Answer

A) The principal factor is mass 
B) The principal factor is density 
C) The principal factor is temperature 
D) The principal factor is luminosity 
A) The principal factor is mass 
B) The principal factor is density 
C) The principal factor is temperature 
D) The principal factor is luminosity

Question 15

One of Edwin Hubble's discoveries is that the known universe is expanding. This means that

Accepted Answer

A) most all observable galaxies are moving away from each other. 
B) light rays bend as they near the event horizon of a black hole. 
C) light rays undergo acceleration as they travel vast distances. 
D) the mass of the universe is slowly dissipating. 
A) most all observable galaxies are moving away from each other. 
B) light rays bend as they near the event horizon of a black hole. 
C) light rays undergo acceleration as they travel vast distances. 
D) the mass of the universe is slowly dissipating.

Question 16

Summer and winter constellations are different because

Accepted Answer

A) of the spin of the Earth about its polar axis. 
B) the night sky faces in opposite directions in summer and winter. 
C) of the tilt of the Earth's polar axis. 
D) the Earth is at the solar perigee in winter and apogee in summer. 
E) the universe is symmetric. 
A) of the spin of the Earth about its polar axis. 
B) the night sky faces in opposite directions in summer and winter. 
C) of the tilt of the Earth's polar axis. 
D) the Earth is at the solar perigee in winter and apogee in summer. 
E) the universe is symmetric.

Question 17

What will be the predominant element within the Sun after it has died?

Accepted Answer

A) Helium 
B) Nitrogen 
C) Carbon 
D) Phosphorous 
A) Helium 
B) Nitrogen 
C) Carbon 
D) Phosphorous

Question 18

A pulsar is likely a

Accepted Answer

A) throbbing star in its death throes. 
B) black hole companion. 
C) spinning neutron star. 
D) binary star with a dark companion. 
A) throbbing star in its death throes. 
B) black hole companion. 
C) spinning neutron star. 
D) binary star with a dark companion.

Question 19

As more and more mass falls into a black hole, the radius of its photon sphere

Accepted Answer

A) increases. 
B) decreases. 
C) remains unaffected. 
A) increases. 
B) decreases. 
C) remains unaffected.

Question 20

In which city is Polaris highest in the sky?

Accepted Answer

A) Singapore 
B) Mexico City 
C) Denver 
D) Anchorage 
E) All the same, depending on the time of night 
A) Singapore 
B) Mexico City 
C) Denver 
D) Anchorage 
E) All the same, depending on the time of night

Exam 27: Stars and Galaxies

It is theorized that a pulsar only emits X-rays and visible light during its early history. What do you suppose is the basis of this theory?

The Milky Way is

A Starburst galaxy has this name because of its

What is the upper limit of stars the unaided eye can discern on a moonless night in a rural area?

What prevents stars greater than about 100 times the Sun's mass from existing?

Quasars are

Galaxies are aggregations of stars, stellar dust, and gas. Their masses

Which star will emit the shortest wavelength of its peak frequency?

Most of the stars in colliding galaxies

Why does a star's color corresponds to its temperature?

The temperature of a star is evidenced by its

The Milky Way galaxy is

Compared to most stellar objects, quasars are more

What determines if a star becomes a white dwarf, a neutron star, or a black hole?

One of Edwin Hubble's discoveries is that the known universe is expanding. This means that

Summer and winter constellations are different because

What will be the predominant element within the Sun after it has died?

A pulsar is likely a

As more and more mass falls into a black hole, the radius of its photon sphere

In which city is Polaris highest in the sky?

Patterns of Motion and Equilibrium

Newtons Laws of Motion

Momentum and Energy

Gravity, Projectiles, and Satellites

Fluid Mechanics

Thermal Energy and Thermodynamics

Heat Transfer and Change of Phase

Static and Current Electricity

Magnetism and Electromagnetic Induction

Waves and Sound

Light

Atoms and the Periodic Table

The Atomic Nucleus and Radioactivity

Elements of Chemistry

How Atoms Bond and Molecules Attract

Mixtures

How Chemicals React

Two Classes of Chemical Reactions

Organic Compounds

Rocks and Minerals

Plate Tectonics and Earths Interior

Shaping Earths Surface

Geologic Timereading the Rock Record

The Oceans, Atmosphere, and Climatic Effects

Driving Forces of Weather

The Solar System

The Structure of Space and Time

Prologue: the Nature of Science

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