Download ASTR1010_Exam3_Sp11

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NAME________________________________________________________________________________________
ASTR 1010 – THIRD EXAM
Friday, April 22, 2011
Professor Loris Magnani
There are 33 questions on this exam. Write your answer right on this exam either
by circling one of the 5 choices or writing the letter corresponding to your choice
next to the question. If you circle more than one answer, make sure you make clear
to me which answer is your actual choice, because if I have any doubts, I will just
mark the question as being wrong. Each correct answer is worth 3 points for a total
of 99 points. There is also a bonus question at the end of the exam that is worth 3
points. Since everyone gets 1 free point for writing their name in the space above,
the maximum score you can get on the exam is 103. There is only one best answer
to each question. There is a sheet at the end of this exam with formulas and
constants that you may need. You may use a calculator. GOOD LUCK!
1. The Earth’s current atmosphere is composed primarily of
a) nitrogen
b) oxygen
c) carbon dioxide
d) water vapor
e) hydrogen
2. In addition to volcanic outgassing, what other mechanism produced the
secondary atmospheres of the terrestrial planets?
a) the solar wind
b) the Sun’s magnetic field
c) the planet’s magnetic field
d) cometary impacts
e) plate tectonics
3. Water pressure in the Earth’s oceans increases by 1 bar for every 10 meters of
depth. Approximately how deep would have to go to experience pressures equal
to the atmospheric surface pressure on Venus?
a) 1 meter
b) 10 meters
c) 100 meters
d) 1 kilometer
e) 10 kilometers
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4. Which of the following is not considered a greenhouse gas?
a) water vapor
b) methane
c) oxygen
d) carbon dioxide
e) chlorofluorocarbons
5. What is the heating mechanism for the stratosphere?
a) terrestrial infrared radiation
b) optical light from the Sun
c) x-rays from the Sun
d) solar wind particles
e) ultraviolet radiation from the Sun
6. Jupiter’s composition most nearly resembles which of the following objects?
a) the Sun
b) Venus
c) the Earth
d) a comet
e) an asteroid
7. What are the characteristics of the jovian planets in contrast to those of the
terrestrial planets?
a) large sizes, high density, rings, many satellites
b) small sizes, low density, many satellites
c) large sizes, low density, rings, many satellites
d) small sizes, high density, many satellites
e) large sizes, low density, cryovolcanoes
8. The belts and zones seen in Jupiter’s outer atmosphere are produced by a
combination of Hadley circulation, fast rotation and what other mechanism?
a) the Second Law of Thermodynamics
b) the Coriolis effect
c) synchrotron radiation
d) thermal radiation
e) all of the above
9. In a magnetic field, fast-moving charged particles produce a type of radiation
know as
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a)
b)
c)
d)
e)
thermal radiation
Compton scattering
magnetic resonance radiation
Kelvin-Helmholtz radiation
synchrotron radiation
10. What is the source of color in Jupiter’s atmosphere?
a) methane
b) different compounds forming icy layers at different heights
c) heat from the planet’s interior
d) different isotopes of oxygen
e) carbon dioxide
11. The distance from the center of a planet to the point where an asteroid or a
moon would begin to break up is called
a) the Roche Limit.
b) the Schwarzschild Radius.
c) the Parsifal Mosaic.
d) the Helmholtz Region.
e) the Neufeld Zone.
12. The gaps in the asteroid belt produced by a resonance with Jupiter are called
a) Neufeld Zones
b) Kirkwood Gaps
c) A’Hearn Gaps
d) Van Nostrand Zones
e) None of the above
13. Where can one find the Trojan Asteroids?
a) six degrees east and west of Jupiter along the ecliptic
b) at the Earth’s L5 equilibrium point
c) between the orbits of Mars and Jupiter
d) between the orbits of Earth and Mars
e) 60 degrees east and west of Jupiter, along Jupiter’s orbit
14. The tidal bulge raised by the Earth on the Moon produces a slowing of the
Earth’s rotational period. What happens to the Moon?
a) It gets closer to the Earth.
b) It moves farther away from the Earth.
c) Its rotational period also increases.
d) Its rotational period decreases.
e) Nothing.
15. Libration of the Moon is produced by tidal bulge of the Moon always pointing
towards the Earth and by
a) the Moon’s increase in angular momentum.
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b)
c)
d)
e)
the Earth’s changing velocity as it orbits the Sun.
the Moon’s changing velocity as it orbits the Earth.
Spring and Neap tides.
spin-orbit resonances.
16. Mars’ atmosphere is currently composed primarily of
a) oxygen.
b) nitrogen.
c) argon.
d) carbon dioxide.
e) carbon monoxide.
17. What is the gas in the Earth’s stratosphere that absorbs ultraviolet radiation?
a) oxygen
b) water vapor
c) deuterium
d) methane
e) ozone
18. The Earth’s naturally occurring greenhouse effect raises the Earth’s
temperature by about
a) 3 degrees
b) 12 degrees
c) 23 degrees
d) 35 degrees
e) 58 degrees
19. The primary atmospheres of the terrestrial planets were composed of
a) hydrogen and helium
b) water vapor and carbon dioxide
c) methane and nitrogen
d) carbon dioxide and water vapor
e) carbon dioxide and nitrogen
20. Order the following from lowest atmospheric pressure to highest atmospheric
pressure at the surface:
a) Earth, Venus, Mars
b) Mars, Venus, Earth
c) Venus, Earth, Mars
d) Earth, Mars, Venus
e) Mars, Earth, Venus
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21. The equilibrium temperature for Jupiter should be 109 K, but instead we find
an average temperature of 124 K. How much more energy is Jupiter radiating
into space than it absorbs from the Sun?
a) 9% more
b) 24% more
c) 67% more
d) 88% more
e) 109% more
22. Why is Jupiter’s atmosphere more colorful than that of Saturn?
a) The composition of Jupiter is substantially different from that of Saturn.
b) Jupiter’s larger gravity compresses the various layers of its atmosphere
so that we can see deeper into it.
c) Saturn’s faster rotation forces the colorful layers deeper into its
atmosphere.
d) The magnetosphere of Jupiter produces stronger auroras which, in turn,
produce a more colorful atmosphere.
e) Jupiter’s faster rotation dredges up more colorful compounds from its
interior.
23. The magnetosphere of Jupiter is produced by its interior layer of
a) liquid molecular hydrogen
b) liquid ammonia and methane
c) iron-nickel
d) metallic hydrogen
e) anhydrous ammonia
24. The charged particles in Jupiter’s plasma torus come primarily from
a) comets
b) the solar wind
c) Europa
d) Interstellar space
e) Io
25. The marked oblateness of the giant planets is produced by
a) their large magnetospheres
b) the angular momentum from their ring systems
c) their rapid rotation
d) the angular momentum from their satellites
e) all of the above
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26. How much stronger would the lunar tides be if the Moon was half of its current
distance from the Earth?
a) They would be the same strength.
b) They would be twice as strong.
c) They would be half as strong.
d) They would be four times as strong.
e) They would be eight times as strong.
27. What is a Lagrangian point?
a) A place where solar tides are highest.
b) A point where a body is in gravitational equilibrium.
c) A point in an elliptical orbit where the Sun’s gravity is strongest.
d) A place where solar tides are weakest.
e) A place where lunar tides are weakest.
28. Synchronous rotation is an example of what kind of orbital resonance?
a) 1:1
b) 1:2
c) 1:4
d) 2:1
e) 4:1
29. Imagine that you could drill a hole from one side of the Earth, through the
center, and out the other side. If you lowered yourself into the hole, all the way
to the center of the Earth and stayed there, what would be your weight at the
center of the Earth?
a) Zero; you would be weightless.
b) Your weight would not change from its value at the surface.
c) Your weight would double.
d) Your weight would equal that of the Earth.
e) Your weight would be infinite.
30. Calculate the orbital radius of the Kirkwood gap that is in a 4:1 orbital
resonance with Jupiter. Take Jupiter’s period around the Sun to be exactly 12
years.
a) 1.6 AU
b) 2.1 AU
c) 2.5 AU
d) 4.0 AU
e) 5.2 AU
31. What is the most common element on Jupiter and Saturn?
a) hydrogen
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b)
c)
d)
e)
helium
nitrogen
oxygen
carbon
32. If Earth’s atmospheric pressure at sea-level is 1 bar, approximately what is the
surface atmospheric pressure on Mars?
a) 0.001 bar
b) 0.01 bar
c) 0.1 bar
d) 1 bar
e) 10 bar
33. We know that running water must have once been present on the surface of
Mars. What does that say about the atmosphere of the planet at that time?
a) It must have been thinner back then.
b) It must have been composed primarily of nitrogen.
c) It must have been composed primarily of hydrogen and helium.
d) It must have been thicker back then.
e) It must have been much colder back then.
SPECIAL BONUS QUESTION (3 points):
Approximately how much stronger is Jupiter’s magnetic field compared to that of
the Earth (comparing the strength of the field at the Earth’s surface and the Jovian
cloud tops).
a) They’re the same strength.
b) Jupiter’s is 10 times stronger
c) Earth’s is 10 times stronger
d) Jupiter’s is 100 times stronger
e) Earth’s is 100 times stronger