Download practice exam #1

PRACTICE EXAM #1
PSCI 131
WINTER 2014
This exam will not be turned in or graded. Keep it as a study aid. The material on this exam is meant to
give you an idea of what to expect on the real thing; it is not meant to be exhaustive. The format of this
practice test is representative of the format of the real exam; you can expect to see these kinds of question
formats.
ORIGINS OF ASTRONOMY
1. Earth’s seasons are produced by its ___ around the Sun.
a. Rotation
b. Revolution
c. Precession
d. Contraction
e. A and B
f. B and C
2. The ancient Greeks were aware of seven celestial objects that move relative to the background of stars.
These are the Sun, Moon, Earth, and the planets that can be seen without a telescope. TRUE or FALSE
3. When Eratosthenes calculated Earth’s circumference, he used measurements of shadows cast at two
different cities on the same day, and
a.
b.
c.
d.
e.
f.
g.
The distance between those cities in degrees of latitude
The fact that Earth always casts a curved shadow during an eclipse
The distance between those cities in length units (stadia)
Algebraic theorems
A and D
C and D
A and C
4. When Aristarchus proposed that the universe is heliocentric, most other Greek thinkers rejected this idea
because, if it were true, stellar parallax should have been observed. Parallax was not seen by the ancient
Greeks because______________________________________________________________.
5. The Copernican Revolution in Renaissance Europe was
a. The spread of the idea of a heliocentric solar system
b. The takeover of scientific academies by the Church
c. The spread of the idea of a geocentric solar system
d. The arrest of hundreds of prominent scientists for heresy
e. None of the above
6. The fact that a planet is not always the same distance from the Sun, and changes orbital speed during its
year, are consequences of Johannes Kepler’s
a. First Law of Planetary Motion
b. Second Law of Planetary Motion
c. Third Law of Planetary Motion
d. A and B
e. B and C
f. A and C
7. Kepler’s Third Law, p2 = d3, states that period of revolution is proportional to orbital distance. If a
hypothetical planet’s period of revolution is 8 Earth years, what is its orbital distance? Show all
calculations in a legible and orderly way.
Orbital distance: _______ AUs
8. Which of the following is NOT one of Galileo’s contributions to modern astronomy?
a. Observation of the phases of Venus
b. Discovery of moons orbiting a planet other than Earth
c. Discovery of sunspots
d. Observation of asteroids
e. All of the above are contributions made by Galileo
9. Sir Isaac Newton showed that planetary orbits are a balance between the forces of _________ and
__________.
10. Using the moon phases figure below, determine the correct rise time for the third-quarter moon.
a. Noon
b. Sunrise
c. 3 AM
d. Midnight
THE SOLAR SYSTEM
(You will need the Planet Data Table below for some of the questions in this section.)
11. What do astronomers suspect is the reason for the high-density planets being close to the Sun, and the
low-density planets further away?
a. The low-density planets all have weaker gravity, so they have moved further away
b. The high-density planets have very strong magnetic fields that pull them closer
c. During solar system formation, the inner solar system was too hot to retain most ice and gases
d. Astronomers don’t know why
12. Which of the following is NOT a difference between terrestrial and Jovian planets? (circle one answer)
a. Diameter
b. Atmospheric thickness
c. Length of year
d. Length of day
e. Average density
f. Distance from the Sun
g. All of the above are differences between terrestrial and Jovian planets
13. By definition, a major planet has not cleared its orbital path of other objects. TRUE or FALSE
14. The terrestrial planet with the shortest day is ___________.
15. The Jovian planet with the lowest average density is __________.
16. The surface of Venus is the hottest known place in the solar system. Why is its surface so hot?
a.
b.
c.
d.
e.
It has intense volcanism
It radiates a great deal of heat from its interior
Its atmosphere is mostly carbon dioxide
Its atmosphere is mostly methane
None of the above
17. Four of the five officially recognized dwarf planets are located in the Kuiper Belt, which is located
a. Between Mars and Jupiter
b. Between Uranus and Neptune
c. Beyond Neptune
d. None of the above
18. Examine the photo below. Would it be correct to call this object a dwarf planet? Why or why not?
19. In which direction is this comet traveling?
a. To the left
b. To the right
c. Can’t tell from photo
LIGHT, ASTRONOMICAL OBSERVATIONS, AND THE SUN
20. Different wavelengths of visible light are detected by our eyes as different
a. Pitches
b. Colors
c. Shifts
d. Nebulas
e. Trajectories
21. Selective absorption refers to the absorption of unique patterns of __________ by different _________.
22. Which type of spectrum is most often used to determine the composition of a star?
a. Dark-line
b. Bright-line
c. Continuous
d. All of the above
23. The constellation Orion contains a red star and a blue star. Which star is hotter? ____________
24. If Star A is 10 times hotter than Star B, then Star A is emitting ___ times as much energy as B.
a. 10
b. 100
c. 1,000
d. 10,000
e. 100,000
f. 1,000,000
25. Which spectrum in the figure below is from an object that is approaching Earth? ______________
26. Why can’t refracting telescopes be very large?
a. Chromatic aberration problems increase as lens size increases
b. Large lenses are too heavy to be practical
c. Large lenses must be flawless in order to produce good images
d. The focal point of a large lens is too close to the lens
e. None of the above
27. Explain why the collecting dishes of radio telescopes must be much bigger than the mirrors of reflecting
telescopes.
28. The majority of the energy the Sun radiates into space is in the ______________ band of the
electromagnetic spectrum.
29. Which of the following is the deepest solar layer (out of the ones listed)?
a.
b.
c.
d.
e.
Convection zone
Photosphere
Corona
Radiation zone
Chromosphere
30. What solar layer is the source of the solar wind? _____________________
31. The Sun consumes _____________ and produces ___________ and ___________.
BEYOND THE SOLAR SYSTEM
32. Since the Big Bang, about 14 billion years ago, the universe has been ___________.
a. Contracting and heating
b. Expanding and cooling
c. Contracting and cooling
d. Expanding and heating
33. Observations by the Hubble telescope tell astronomers that galaxies seem to be evenly distributed
throughout space. TRUE or FALSE
34. What is the difference between an emission nebula and a reflection nebula?
35. Which area of the Hertzsprung-Russell diagram does a typical star spend most of its life cycle in?
36. What event marks the transition from the nebular to the protostar stage in a star’s life cycle?
a. Gravitational collapse of the core
b. Expansion of the outer shell
c. A supernova
d. Start of nuclear fusion reactions in the core
e. Depletion of hydrogen in the core
37. The stellar life cycle is governed by the balance between the two opposing forces of ________________,
which promotes expansion, and ____________, which promotes contraction.
38. Briefly explain why the surface temperature of a red giant star is cooler than that of a main sequence star,
even though the temperature in a red giant’s core is much hotter than a main sequence star’s core.
39. Heavy elements like gold, uranium, and copper are created by fusion of lighter elements in a
a. Supernova
b. White dwarf
c. Black hole
d. Low-mass star’s core
e. All of the above
40. If black holes are black (i.e. radiation cannot escape their gravity, and therefore they can’t be seen
directly), how have astronomers been able to detect their presence? Explain in one or two brief
sentences.