Reference no: EM131640020

Assignment

Question 1
Which of the following has been suggested as a possible explanation for the solar neutrino problem?
A. Our detection methods are not adequate for the type of solar neutrino that strikes Earth.
B. The production of solar neutrinos millions of years ago may have been less.
C. Our theory of energy production within the Sun may be incorrect.
D. [All of the above.]
E. [None of the above.]

Question 2
Of a group of main sequence stars, the star with the greatest mass also has the
A. greatest luminosity.
B. greatest absolute magnitude.
C. greatest temperature.
D. [Both A and C.]
E. [Both B and C.]

Question 3
Which atom can emit or absorb radiation at a wavelength of 21.1 centimeters?
A. Neon
B. Oxygen
C. Carbon
D. Hydrogen
E. Helium

Question 4
In the center of the Crab nebula we have detected
A. a protostar.
B. a neutron star.
C. a black hole.
D. a white dwarf.
E. [None of the above.]

Question 5
What keeps nuclear fusion from going out of control in a main sequence star?
A. If the reaction were to increase, the core would expand and slow the reaction.
B. Nearby stars exert enough gravitational force to control the reaction.
C. Fusion absorbs heat, so the reaction limits itself.
D. Gravitational force toward the outer part of the star keeps the core under control.

Question 6
About 99.98% of an atom's mass is in its
A. protons and electrons.
B. protons.
C. protons and neutrons.
D. neutrons and electrons.
E. electrons.

Question 7
What pushes parts of a GMC away from an EGG and exposes it?
A. Nuclear forces
B. Gravitational forces
C. Radiation

Question 8
As light passes through the interstellar medium, it
A. causes an effect that cannot be distinguished from the Doppler effect.
B. becomes more red in color.
C. becomes more blue in color.
D. becomes brighter.

Question 9
Using the measured proper motion of a star and its distance, we can calculate the star's
A. tangential velocity.
B. radial velocity.
C. spectral class.
D. absolute magnitude.
E. space velocity.

Question 10
The order of stages in the evolution of a star like the Sun is
A. white dwarf, main sequence star, red giant.
B. red giant, white dwarf, main sequence star.
C. main sequence star, white dwarf, red giant.
D. white dwarf, red giant, main sequence star.
E. main sequence star, red giant, white dwarf.

Question 11
Supernova 1987A is located in
A. Ursa Major.
B. Cepheus.
C. Orion.
D. the Large Magellanic Cloud.
E. Cygnus.

Question 12
The primary method by which energy is transported from the center of the Sun to its surface is
A. conduction.
B. convection.
C. radiation.
D. [Two of the above about equally.]
E. [All of the above about equally.]

Question 13
Which of the following contains a neutron star within it?
A. The Crab Nebula
B. A Cepheid variable
C. A dark nebula
D. A pulsar
E. [None of the above.]

Question 14
Gravitation was once used to explain the source of the Sun's energy. What new data caused this theory to be abandoned?
A. Measurements of changes in the size of the Sun
B. Measurements of the changes in the Sun's luminosity
C. A new value for the total luminosity of the Sun
D. A more correct value for the Earth's distance from the Sun
E. A new value for the age of the Sun and Earth

Question 15
The Sun's mass is about __________ times larger than the Earth's mass.
A. 300,000
B. 3,000
C. 300
D. 30

Question 16
The absolute magnitude of a typical supergiant star is about
A. +5.
B. +12.
C. -5.
D. 0.

Question 17
Interstellar clouds are
A. slightly less dense than air at sea level on Earth.
B. much less dense than air at sea level on Earth.
C. more dense than air at sea level on Earth.
D. about the same density as air at sea level on Earth.

Question 18
Deep within the Sun, the pressure is
A. greater than near the surface.
B. less than near the surface.
C. the same as near the surface.

Question 19
Solar neutrino detectors are located
A. in dry climates, for humidity deflects solar neutrinos.
B. on high mountains so that solar neutrinos can reach them.
C. in space so that solar neutrinos can reach them.
D. in deep mines below the Earth.
E. anywhere on Earth's surface, for solar neutrinos easily penetrate the atmosphere.

Question 20
A star with an apparent magnitude of 3 emits _____ times as much energy as a star with an apparent magnitude of 5.
A. 2
B. [The answer cannot be determined from the information given.]
C. 0.6
D. 2.5
E. 6.25

Question 21
A neutron is
A. the negatively charged object that circles an atom's nucleus.
B. the neutral object that circles an atom's nucleus.
C. the positively charged object that circles an atom's nucleus.
D. the neutral massive object in the nucleus of an atom.
E. the positively charged massive object in the nucleus of an atom.

Question 22
Nebulae are
A. dust and gas clouds within our solar system.
B. interstellar dust and gas clouds.
C. dust and gas clouds on planets.
D. [Both A and C.]

Question 23
Lighter elements are fused into elements more massive than iron in
A. the core of any star.
B. a pulsar.
C. the core of a massive star, but not a star of low mass.
D. a planetary nebula.
E. a supernova.

Question 24
"The process of absorbing radiation of one frequency and re-emitting it at a lower frequency" is a definition of
A. incandescence.
B. reflection.
C. cirrus.
D. fluorescence.
E. the T Tauri effect.

Question 25
The physical process which causes RR Lyrae stars to be variable is
A. similar to that for Cepheid variable stars.
B. essentially the same as for Cepheid variable stars.
C. [The question is misleading. RR Lyrae stars are not variables.]
D. completely different than that for Cepheid variable stars.

Question 26
The spectra of spectroscopic binaries changes regularly due to
A. changes in the temperatures of the stars as they revolve.
B. changes in the size of the stars as they revolve.
C. changes in the absolute magnitudes of the stars as they revolve.
D. the Doppler effect.
E. [A, B, and C.]

Question 27
Stars are formed from
A. the expansion of dense objects such as black holes.
B. the collapse of galaxies.
C. the expansion of white dwarfs.
D. the collapse of constellations.
E. the collapse of interstellar clouds.

Question 28
Relative to most other stars, a white dwarf is
A. hot and dim.
B. hot and bright.
C. cool and dim.
D. cool and bright.

Question 29
A red giant typically ejects _______ of its mass as a shell in a planetary nebula.
A. 1%
B. more than 90%
C. 0.01%
D. up to 60%

Question 30
Which of the following is an example of a spectroscopic-eclipsing system?
A. Algol
B. Rigel
C. Sirius
D. Polaris

Question 31
The discovery of pulsars can best be described as
A. intentional, since Bell and Hewish were searching for them.
B. accidental, since Hulse and Taylor were looking for something else.
C. intentional, since Hulse and Taylor were searching for them.
D. accidental, since Bell and Hewish were looking for something else.

Question 32
Most pulsars have periods of pulsation in the range
A. between 10-3 seconds and a few seconds.
B. between 10-6 and 10-3 seconds.
C. between a few minutes to a few hours.
D. between a few hours to a few days.

Question 33
The _______ is the region of the Sun primarily responsible for the Sun's spectrum.
A. chromosphere
B. corona
C. photosphere
D. core

Question 34
The H-R diagram is a plot of
A. luminosity versus period of variation for variable stars.
B. luminosity versus temperature of a group of stars.
C. apparent brightness versus luminosity of a group of stars.
D. apparent brightness versus distance for stars near to the Sun.

Question 35
If a star is relatively bright and cool, it must be relatively
A. nearby.
B. distant.
C. large.
D. small.
E. [None of the above follows from the information given.]

Question 36
A "stellar wind" is
A. a disturbance within a giant molecular cloud.
B. the first movement of a protostar.
C. material flowing outward from a star.
D. [None of the above.]

Question 37
When a star is in hydrostatic equilibrium,
A. it is expanding rapidly.
B. the downward forces on each layer are balanced by upward force so the star neither expands nor contracts.
C. the star's energy is trapped inside, so none is released from the surface.
D. it is contracting rapidly.

Question 38
By the time the Sun leaves the main sequence, it will be
A. less massive than it is today.
B. more luminous than it is today.
C. cooler than it is today.
D. [All of the above.]
E. [Both A and B.]

Question 39
How can a cool star have a great absolute luminosity?
A. The star has a very large radius.
B. It can be a main sequence star.
C. It can't.
D. The star is far away from us.
E. The star is close to us.

Question 40
Giant molecular clouds, which are major sites of star formation, can be up to
A. 10 times the size of the solar system and contain 2 to 3 solar masses of material.
B. 100 pc across and contain 2 million solar masses of material.
C. 10 pc across and contain a few thousand solar masses of material.
D. 1,000 pc across and contain 100 million solar masses of material.