Reference no: EM132450527

1. According to Einstein's General Relativity Theory, the universe has three possible futures (in the absence of any dark energy and/or acceleration).  Which one is correct depends only on the average density of mass in the Universe.  Why is this?a. The density of mass determines the rate of formation of black holes which will eventually collapse the Universe.b. The density of mass tells us whether new matter is constantly forming, thereby producing a steady-state.c. The density of mass tells us the critical value of dark matter which will causes the Universe to be static.d. The density of mass determines the strength of gravity, which counters the expansion rate.
2. What is the essence of the Big Bang Theory?a. A massive explosion created all of the heavy elements in the early universe.b. Dark energy is causing the universe to clump together and eventually it will collapse.c. At one time the universe was very small but it expanded, and is continuing to expand today.d. Heavy elements formed in the early universe as a result of a brief period of rapid fusion.
3. Most of the matter in the universe consists of...a. protons and neutrons.b. fundamental particles, yet to be discovered.c. stray planets and brown dwarfs too dim to be detected by today's telescopes.d. unknown at this time (dark matter).
4. The redshift of distant galaxies in the universe is interpreted as (in Einstein's General Theory of Relativity)...a. galaxies are flying apart from some central explosion.b. the difference in temperatures of distant and nearby galaxies.c. space itself is expanding with time and the wavelengths of light is stretched by the expanding space.d. the slowing of the light (tired light theory).
5. If the average density of mass in the Universe is half the critical density, the Universe will likely...a. collapse.b. expand forever.c. stop expanding but not collapse.d. undergo rapid deflation.
6. Production of protons and antiprotons occurs when...a. the energy of two colliding photons is equal to or greater than the combined mass-energy of a proton/anti-proton pair.b. electron and positron pairs are produced.c. photons at the event horizon of a black hole gain energy from the black hole to produce a proton/anti-proton pair.d. one electron is struck by a sufficiently high energy photon and a proton/antiproton pair forms.
7. What does Einstein's Theory of Special Relativity tell us?a.  Time is not absolute, but stretchy like elastic.b.  Time is compressed by accelerating to high speeds.c.  Mass is increased by accelerating to high speeds.d.  All of the above.
8. Quasars are star-like objects at extreme distances but we can still see them. Why?a. They must be very large.b. They must be very small.c. They must be stars.d. They must be producing very large quantities of energy.
9. The energy source in Seyfert galaxies is thought to be compact. Why?a. The light spectra is similar to those produced by stars in globular clusters.b. The energy is non-stellar in origin.c. We can see the source and it appears compact.d. The luminosity varies on rapid time scales which means they are limited in size.
10. What is the importance of Hubble's Constant?a. it describes the temperature fluctuations in the Cosmic Microwave Background.b. it describes the minimum density needed for gravity to overcome the expansion of the Universe and cause it to collapse.c. it describes the decoupling of photons from matter about 300,000 years after the Big Bang.d. it describes the expansion rate of the Universe, and inversely the age of the Universe.
11. Why do some galaxies have such high red shifts?a. They are spinning.b. They are moving rapidly toward us.c. They are moving faster than the speed of light.d. They are very distant and the space between here and there is expanding.
12. What are some of the observations consistent with the Big Bang Theory?a. The current cosmic background radiation temperature is predicted by the theory.b. The abundance of the lighter elements in the Universe is predicted by the theory.c. The evolution of galaxies and large-scale structure of the Universe matches predictions by the theory.d. All of the above.
13. Which of the following best describes quasars?a. Most are high above the galactic plane.b. Actually, astronomers have been unable to determine the spatial distribution of quasars.c. Located in all directions, they exhibit very high red-shifts.d. Most are in the direction of the Milky Way core, they are are between about 3 and 5 billion light years distant.
14. Which of the following is a characteristic of active galaxies?a. Their energy output is steady in timeb. They generally exhibit no signs of explosive activity.c. They are generally less luminous than normal galaxies.d. Their energy emission cannot be explained as the accumulated emission of their stars.
15. Why might a galaxy cluster cause lensing of a more distant galaxy behind it?a. Because of a magnetic field from a supermassive black hole.b. Because of all the dark energy in the halo of the cluster.c. Because of intervening matter and dark matter.d. Because of all the black holes in the cluster.
16. What does Hubble's Law imply about the history of the Universe?a. Before the Universe started to expand, it had collapsed and expanded many times before.b. The Milky Way galaxy is near the location where the Universe started to expand after it formed.c. The Universe has been expanding forever; it is infinitely old.d. The Universe was once smaller and started expanding at some time in the past.
17. Light from every galaxy outside our local group is redshifted. What is the implication of this?a. The universe is expanding.b. We are precisely at the center of the Universe.c. There should be an equal number of galaxies that are blueshifted out there somewhere.d. The universe is static and unchanging.
18. By what method do we measure the most extreme distances in the universe?a. By using the period of Cepheid variable stars.b. By using the Tully-Fisher correlation.c. By using the trigonometry of Geometric Parallax.d. By using Hubble's law and redshift.
19. Why do we appear to be in the center of the Universe?a. Space is curved, distorting the light coming from objects near us.b. Space is expanding, carrying all galaxies away from each other.c. We are in the center of the Universe.d. Hubble's constant is too small to measure.
20. What observation eventually led astronomers to the Big Bang Theory?a. Einstein's General Relativity Theory.b. Einstein's Special Relativity Theroy.c. Redshift measurements of galaxies indicate an overall expansion of the Universe.d. Active galaxies are undergoing close interaction with other galaxies.