Download –1– AST104 Sp06: Welcome to EXAM 2 Multiple Choice Questions

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AST104 Sp06: Welcome to EXAM 2
Multiple Choice Questions: Mark the
best answer choice on the bubble form.
Read all answer choices before making
selection. BEFORE YOU TURN IN
THE EXAM, CAREFULLY RE-CHECK
ALL OF YOUR ANSWERS
1. Which dominates the atmosphere of Earth?
a. hydrogen
b. nitrogen
c. oxygen
d. ozone
e. carbon dioxide
2. Which best characterizes the order of stages
in the Moon’s history?
e. outgassing
4. As a black body is cooled, what is true about
the wavelength at which the most energy per
unit time per unit area is emitted?
a. it decreases
b. it increases
c. the wavelength stays the same but the
frequency will increase
d. the wavelength stays the same but the
frequency will decrease
e. whether the wavelength increases or
decreases is impossible to determine without
knowing what units energy is measured in
5. Relative to the light received from a star
moving away from us, the light received from a
similar star at rest would be
a. cratering, differentiation, slow surface
evolution, flooding
a. blue shifted
b. differentiation, cratering, flooding, slow
surface evolution
c. indistinguishable
c. cratering, differentiation, flooding, slow
surface evolution
e. absorbed
d. flooding, differentiation, cratering, slow
surface evolution
e. the above stages are for planets and the
Moon’s history does not fit into this framework
b. red shifted
d. undetectable
6. What is NOT true about nuclear fusion?
a. it is an insignificant source of heat in
planets
b. it explains the luminosity of stars
3. Which stage of planet evolution is dominated
c. it releases energy in accordance with
by micrometeorites on Mercury?
Einstein’s equation E = mc2
a. slow surface evolution
b. cratering
d. it occurs in the solar corona
c. differentiation
e. it involves reactions that convert smaller
atomic nuclei into larger atomic nuclei
d. flooding
7. Atoms with the same number of protons but
–2–
with an unequal number of neutrons are called
a. isotopes
b. isobars
c. neutrinos
d. nuclei
e. ions
8. For which of the following is the Doppler
effect the most useful?
a. determining the speed at which the
moon orbits the Earth
b. determining the ellipticity of a planet
c. determining whether a distant star may
have massive planetary companion
d. determining the energy contained in a
blackbody of measured temperature
e. determining the shape of Venus’ surface
9. A blackbody is embedded at the center of
a large, low density hydrogen gas cloud. From
which view would we see BOTH an emission
and absorption spectrum?
a. looking through the cloud with the
blackbody along our sight line
b. looking through the cloud with the
blackbody not along our sight line
c. along every line of sight
d. along a line of sight that does not
intersect the cloud
e. none of the above
10. An excited hydrogen atom
c. has its electron in the ground state
d. can emit a photon when the electron
moves to a higher energy level
e. can emit a photon when the electron
moves to a lower energy level
11. Sunspots are
−−−−−−
a. hotter than their surroundings
b. cooler than their surroundings
c. helpful for identifying solar rotation
d. a and c
e. b and c
12. For which of the following do magnetic
fields NOT play an important role?
a. coronae on Venus
b. sunspots
c. solar corona
d. Earth’s auroras
e. solar prominences
13. The solar corona is
a. hotter than the solar photosphere
b. denser than the solar photosphere
c. denser than the solar interior
d. the primary source of the sun’s energy
e. a region of volcanic activity on the sun
14. Why is the average crater size larger on
Venus than on our moon?
a. the moon’s surface is younger
a. is ionized
b. Venus has volcanos
b. is called Deuterium
c. Venus has a thicker atmosphere
–3–
d. water on Venus erodes small craters
e. Venus is farther from the sun
15. Star A emits primarily at a wavelength of
λA = 600nm and Star B emits primarily at a
wavelength of λB = 1200nm. What is the ratio
of the energy emitted per unit time per unit
area of star A to that of star B?
a. 1/2
atmosphere, likely increasing global
warming, while the industrial release of
chlorofluorocarbons −−−−−−− the atmosphere,
increasing the risk of UV ray induced cancer.
a. adds CO2 to ; removes O3 from
b. removes CO2 from ; removes O3 from
c. adds CO2 to ; adds O3 to
d. adds CO2 to ; removes O2 from
b. 1/4
e. removes CO2 from ; removes O2 from
c. 4
19. Which explains why Earth’s atmospheric
flow patterns are broken up into smaller cyclonic
storms than those of Venus’ ?
d. 16
e. 1/16
16. Gravity is important to which of the
following stages of Earth’s evolution?
a. Earth is closer to the sun
b. Earth has a denser atmosphere
a. cratering
c. Earth rotates more quickly
b. differentiation
d. Earth has a molten core
c. slow surface evolution
e. a and b
d. flooding
e. all of the above
17. An astronomer discovers a new planet in
the Solar System. She then observes a small
moon in circular orbit around the new planet.
She measures the moon’s distance from the
planet and the speed of the moon in its orbit.
What can she determine from this information?
a. the mass of the planet
b. condensation, accretion
c. differentiation, sedimentation
e. differentiation, cratering
c. both the planet mass and the moon mass
d. neither mass
21. In comparing Venus with Earth, we find
a. Venus has a negligible amount of CO2 in
the atmosphere compared to Earth.
e. the density of the moon
−−−−−−−
a. accretion, condensation
d. sedimentation, differentiation
b. the mass of the moon
18. Burning fossil fuels
20. In the earliest stages of planet formation,
a microscopic dust grain grows by −−−−−−
when atoms in the surrounding gas stick to the
grain. Later, the grain grows by −−−−−− as it
encounters other grains to which it sticks.
the
b. both have liquid water oceans.
–4–
c. Venus shows no evidence for plate
tectonics, consistent with a more buoyant
pliable crust
d. composite volcanos are common on both
planets
e. because of its stronger magnetic field,
Venus is better protected from the solar wind
22. How did the solar nebula get cleared away?
a. The radiation pressure of sunlight
pushed gas particles outward.
b. The intense solar wind of the Sun
pushed gas and dust outward.
c. The planets swept up gas and dust.
d. Close gravitational encounters with
Jovian planets ejected material outward.
e. All of the above.
23. Volcanic mountains on Earth are formed
a. when heat from Earth’s formation and
radioactive element decay moves crustal plates
against or underneath one another
b. when lava from hot spots beneath the
crust rises up through the surface
c. when the sun is in an active phase of its
cycle and melts the Earth’s crust from above
d. a and b
e. a and c.
24. Which of the following is NOT true about
a comet’s tail?
a. it is longer when the comet is closer to
the sun
b. it always points away from the sun
c. it extends a distance significantly larger
than the diameter of the comet’s nucleus
d. it is made of material released when ices
in in the comet nucleus are vaporized
e. it is produce by fusion inside the comet
25. Rocks on the moon are all −−−−−− , often
−−−−−− , and sometimes −−−−−− .
a. sedimentary, igneous, vesicular
b. igneous, breccias, vesicular
c. sedimentary, iron oxide, igneous
d. anorthosite, sedimentary, igneous
e. regolith, igneous, sedimentary
26. Geological activity could have lasted longer
on Mercury if
a. Mercury rotated faster
b. Mercury were much larger in size
c. Mercury were much smaller in size
d. Mercury had less radioactive elements
e. Mercury were farther from the sun
27. Sinuous rilles are
a. lava channels near maria on the moon
b. water channels on Mars
c. lobate scarps on Mercury
d. bright loops in the solar corona seen
during a solar eclipse
e. crust wrinkles on Venus
28. What is true about Mercury?
a. its rotation period is longer than its
orbit period
b. its rotation period is decreasing
–5–
c. it has active volcanos
d. its long days and long nights lead to
extreme day-night temperature differences
e. its surface is younger than that of Venus
29. How do we know that the core beneath
Earth’s mantle is liquid?
b. Low density materials sink toward the
center and high-density materials rise toward
the surface of a molten body.
c. Only rocky materials can condense
close to the Sun, whereas both rocky and icy
materials can condense far from the Sun.
d. Both rocky and icy materials can
a. Oil drilling has penetrated deep beneath condense close to the Sun, whereas only rocky
the mantle and sampled this liquid
materials can condense far from the Sun.
b. By measuring the presence or absence of
e. Rotation and convection in molten
seismic S waves vs. seismic P waves at different material produce a magnetic field
locations after an Earthquake
32. Using the principles of planet formation,
c. Because lava flows are liquid
what is the expected order from LOW density
to HIGH density?
d. Because liquid water on the surface is
impossible without a liquid core.
a. Jupiter, Mercury, Venus, Mars
e. By putting one’s ear to the ground in
a quiet location, one can hear the liquid core
sloshing around.
30. Which is the LEAST helpful in
distinguishing the Large-Impact model of
the moon’s formation from other models?
a. the measured angular momentum of the
Earth-moon system
b. that the moon is poor in iron
c. that the moon has many craters
d. that moon composition is similar to
Earth’s mantle
e. the moon lacks volatile elements
b. Mercury, Venus, Mars, Jupiter
c. Mars, Jupiter, Venus, Mercury
d. Jupiter, Mars, Venus, Mercury
e. Venus, Mars, Jupiter, Mercury
33. Earth’s atmosphere
atmosphere
−−−−−−
than Mars’
a. is thinner
b. is thicker
c. is redder
d. has a higher fraction of carbon dioxide
e. reveals less evidence for living organisms
34. Why is Mars’ moon Deimos covered with
31. Which of the following accurately describes
more meteoritic debris than its other moon
the differentiation process?
Phobos?
a. High density materials sink toward the
a. because Deimos is farther from Mars
center and low-density materials rise toward the
b. because Deimos has a smaller escape
surface of a molten body.
velocity
–6–
c. because Deimos is not spherical
d. because Deimos orbits Mars in the
prograde direction
e. because Deimos is a captured asteroid
b. the atmospheric temperature
c. the mass of a methane molecule
d. a and c
e. a, b, and c
35. Which best describes what happened to
liquid water that once flowed on Mars?
38. Which of the following is/are important
in preventing a naturally occurring runaway
a. radiation from the sun dissociated water greenhouse effect on a planet?
and the hydrogen escaped while the oxygen got
a. water oceans
trapped in rocks.
b. ozone
b. radiation from the sun dissociated water
c. industrialization
and the oxygen escaped while the hydrogen got
trapped in rocks.
d. active volcanos
c. heat from the currently active volcanos
e. a and b
evaporated the water.
39. Which of the following are true AND
d. gravity pulled the water from high
support the solar nebula hypothesis?
latitudes down to the south pole where the
a. All of the planets orbit the Sun near the
water froze.
Sun’s equatorial plane
e. due to the seep slopes of the river beds,
b. All of the planets orbit in the same
gravity accelerated the flowing water so much
direction
that the Sun rotates.
that the water escaped off the surface
36. The orbital period of the moon around
Earth is about 27 days. What is the rotation
period of the moon about its own axis?
a. 9 days
b. 18 days
c. 27 days
d. 36 days
e. 45 days
37. Which of the following is/are important for
determining whether methane (CH4 ) is retained
by a planet’s atmosphere vs. lost into space?
a. the escape speed of the planet
c. Most planets rotate in the same direction
as the Sun.
d. Young stars are often observed to be
surrounded by gas and dust disks
e. all of the above
40. An astronomer determines that the ratio of
temperatures of two blackbody stars A and B is
TA /TB = 3 What is the ratio of the wavelengths
where the intensity of the radiation spectrum
peaks?
a. λA /λB = 3
b. λA /λB = 72
c. λA /λB = 1/72
–7–
d. λA /λB = 1/9
e. λA /λB = 1/3
True or False:
41. The Zeeman effect allows the strength of
the magnetic field on the sun to be mapped.
42. The solar nebula from which the planets
formed was composed mostly of helium
43. Lunar maria are older than the lunar
highlands.
44. The active plate motions on Earth reduce
the size of shield volcanos compared to those on
Mars and Venus
45. The strength of Balmer lines and the
spectral classification of stellar types (e.g.
O,B,A,F,G,K,M) can be used to infer a star’s
photospheric temperature.
46. We know the average density of each of
the planets because spacecraft have sampled
material from each of them.
47. Convection does not play a significant role
in transporting heat from the interior of the sun
to its surface.
48. The properties of the Earth’s magnetic field
suggest the presence of an active core dynamo.
49. The jumbled terrain on the Moon opposite
to the Imbrium Basin is evidence for plate
tectonics
50. The diameter of the sun is smaller than the
distance between the sun and any of the known
planets of the solar system.
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Answers
28. D
1.B
29. B
2.B
30. C
3.A
31. A
4.B
32. D
5.A
33. B
6.D
34. A
7.A
35. A
8.C
36. C
9.E
37. E
10. E
38. E
11. E
39. E
12. A
40. E
13. A
41. T
14. C
42. F
15. D
43. F
16. E
44. T
17. A
45. T
18. A
46. F
19. C
47. F
20. B
48. T
21. C
49. F
22. E
50. T
23. D
24. E
25. B
26. B
27. A