NAME _____________________________ ID # ____________ LAB # ________
Astronomy 1001 Dr. Thomas W. Jones
Final Exam Fall 2000
Read Instructions Carefully:
The short answer questions of this exam are graded by more than one person, so it is imperative that your NAME BE LEGIBLY WRITTEN ON EACH PAGE OF THE ESSAY PORTION!
1. MARK THE ANSWERS YOU CHOOSE ON THIS TEST AS IT IS YOUR ONLY
OPPORTUNITY TO CHECK WHICH ANSWERS YOU GOT RIGHT OR
WRONG. This will not be done for you at a later time in the departmental office.
Exams will be returned to the alphabetical boxes in the North wall of the Physics
building approximately 3-4 days after the exam.
2. Print your NAME, ID # and SECTION # on your answer sheet where appropriate. Your
SECTION # should read 03. All three items are necessary for the proper scoring and
computer transfer of your scores.
3. Use a pencil, make your marks dark and neat, and erase thoroughly.
4. There is only one answer to each question. Choose the best answer.
5. You may use this test for scratch paper.
6. One page (two sides) of notes is allowed for the exam.
I. Multiple Choice (2 pts. each)
1. The Sun’s corona is characterized by
a) ionized gases
b) hot, low density gas
c) x-ray emission
d) being the source of the solar wind
e) all of a-d
2. When a “compact star” (white dwarf, neutron star or black hole) exists in a binary system with a very close companion “ordinary star,”
a) the ordinary star will explode because of intense gravity
b) mass from the companion may be gravitationally attracted to form a hot “accretion disk” around the compact star
c) a radio pulsar always results
d) the ordinary star is “reborn” as a protostar
e) the two stars will merge to form a quasar
3. The expansion age of the universe is approximately ____________ years
a) 4.5 billion b) infinite c) 15,000,000,000 d) 100 billion years e) 10,000,000
4. Observations show that the Milky Way Galaxy is
a) rotating b) expanding c) contracting d) infinite e) spherical
5. Elliptical galaxies are redder in color than spiral galaxies because they
a) consist primarily of old stars
b) contain a lot of dust
c) contain many planetary nebulae
d) are mostly cold, diffuse gas
e) are seen at low Galactic latitudes where interstellar reddening is strong
6. A nova outburst is caused by a nuclear explosion
a) in the core of a red giant
b) in a sunspot
c) on the surface of a white dwarf in a binary star system
d) within the Schwarzschild radius of a massive black hole
e) on a planet orbiting a white dwarf
7. The mass of a cluster of galaxies can be estimated by measuring the
a) cluster diameter and the average velocity of its galaxies
b) characteristic temperature of its galaxies
c) velocities and distances of its galaxies from earth
d) composition of its gas
e) cluster diameter
8. The convection layer of the sun
a) reaches down to the core where nuclear reactions happen
b) is where radiation carries energy outward
c) includes only some outer layers in the Sun
d) is optically thin (transparent)
e) is restricted to just the central core
9. The greenhouse effect heats a planet because
a) more sunlight gets in
b) the reflection of the upper atmosphere is increased
c) infrared radiation is trapped
d) the winds blow more slowly
e) the sunlight is polarized
10. The method of stellar parallax is a fundamental method for measuring distances to other stars. What basic fact makes this method possible?
a) stars revolve about the center of the galaxy
b) Earth rotates once a day
c) Earth wobbles on its axis
d) Earth revolves around the Sun once a year
e) some stars pulsate
11. Roughly how much older than the Earth is the Universe (measured since the Big Bang)?
a) Only slightly older
b) 15 or 20 times as old
c) more than 30 times as old
d) 2 or 3 times as old
e) unknown
12. A black hole is
a) an old white dwarf star that has cooled off and shrunk
b) a dense object whose gravity can capture light
c) another name for a black body radiator
d) a pulsar with a mass less than 1.4 solar masses
e) the center of a sunspot
13. In general, the red-shifts of normal galaxies
a) are greater for older galaxies
b) are greater for more distant galaxies
c) depend on their temperatures
d) depend on their classification types
e) depend on their predominant types of stars
14. The first clear evidence that we are not near the center of the Milky Way came from studies of
a) the number of distant stars in the plane of the galaxy
b) HII regions
c) the distribution of globular clusters in the sky
d) open (galactic) clusters
e) Cepheid variables
15. In which of the following ways was Earth considerably different 3 billion years ago?
a) At that time, Earth was much more massive, because it had not yet lost much material into space
b) At that time, Earth was much less massive, because it had not yet gathered most of its mass from meteoroids and asteroids
c) Earth was then much closer to the Sun
d) At that time, Earth rotated on its axis only once a year
e) The atmosphere did not contain much free molecular oxygen then
16. The force that holds electrons in an atom is
a) electrical b) gravity c) magnetic d) not known e) weaker than gravity
17. Which of the following is NOT used by astronomers to estimate distances of galaxies?
a) supernovae b) proper motion c) doppler shifts d) Cepheid variables e) red supergiants
18. In the Sun, significant nuclear reactions occur only in the central core. Why?
a) hydrogen is more abundant there than on the surface
b) the pressure and temperature are highest there
c) nuclei are more fragile there
d) nuclei are more stable there
e) there si a black hole at the sun’s center
19. The cosmic abundance of helium traces back to conditions
a) a million years after the Big Bang
b) in the first generation of stars in our galaxy
c) in the cloud that formed the Solar System
d) in the first few minutes of the Big Bang
e) in the center of the Sun today
20. During most of a star's life it produces energy by fusion of
a) uranium to plutonium
b) hydrogen to helium
c) helium to carbon
d) helium to oxygen
e) carbon to oxygen and heavier elements
21. Roughly what percentage of the total mass of all the planets is in Jupiter?
a) 70 b) 10 c) 99.9 d) .01 e) 5
22. Both Venus and Mars have
a) atmospheres of carbon dioxide
b) clouds of sulfuric acid
c) retrograde rotation
d) ice caps of carbon dioxide
e) a day (period of rotation) longer than the year (period of revolution)
23. What is the approximate age of the Earth, estimated from radioactive dating of meteorites and other evidence?
a) 4.5 billion years
b) 4.5 million years
c) 1 million years
d) 20,000,000,000 years
e) 6000 years
24. Massive stars remain on the main sequence
a) longer than less massive stars because they have more fuel
b) for shorter times than less massive stars, because they use up fuel faster
c) about the same lengths of time as less massive stars
d) for lengths of time that are unpredictable
e) massive stars are giants, so not on the main sequence
25. When we observe distant galaxies within reach of our telescopes we are also
a) observing the beginning of the universe
b) observing the edge of the universe
c) looking backwards in time
d) looking forward in time
e) none of a--d
26. The 3K cosmic background radiation is evidence that
a) the Solar System is surrounded by a giant dust cloud
b) the universe is oscillating
c) the universe has expanded from a much denser and hotter state
d) most material in the universe is at 3K
e) the universe was originally cold helium
27. The most likely power source for a quasar is
a) a supermassive star
b) colliding stars
c) a supermassive black hole
d) matter-antimatter annihilation
e) an intense magnetic field
28. Black-body radiation has a wavelength of maximum emission which depends on
a) which types of atoms are present (spectroscopy)
b) temperature
c) density of the matter
d) gas pressure
e) strength of gravity
29. General Relativity predicted
a) deflection of starlight by the Sun
b) the sunspot cycle
c) the strength of the solar magnetic field
d) that other giant planets besides Saturn should have rings
e) nucleosynthesis of helium
30. The most damaging blow to Earth-centered theories of the universe came from the
a) discovery of sunspots
b) fact that bodies of different weight, fall at the same rate
c) discovery that the moon orbits Earth
d) discovery of Jupiter's moons and phases of Venus
e) doppler shifts of stars
NAME _____________________________ ID # ____________ LAB # ________
Astronomy 1001 Dr. Thomas W. Jones
Final Exam Fall 2000
II Short Essay Questions (5 pts. each)
1. Outline briefly key stages in the Big Bang model for evolution of the universe to the present. Be sure to include how cosmic conditions have changed over time and a rough accounting of when the different chemical elements hydrogen (H), helium (He), carbon (C), and oxygen (O) were formed. Also indicate in a similar way when galaxies, clusters and stars formed, and finally indicate when in this picture the sun and earth came into existence.
NAME _____________________________ ID # ____________ LAB # ________
Astronomy 1001 Dr. Thomas W. Jones
Final Exam Fall 2000
2. Briefly compare the accepted cosmology of 15th century Europe to the cosmology of 21st century main stream astronomers. Comment on the size of the universe in the two cosmologies as well as the relationships between the earth, planets, the sun, stars and Milky Way.