1 1) Which of the following statements about globular clusters is false? a) Globular cluster stars are very metal- poor relative to the Sun. b) Globular cluster stars are more than 12 billion years old. c) Globular clusters are distributed spherically around the Milky Way. d) Globular clusters contain many thousands of stars. e) Globular cluster ages increase with distance from the Milky Way. 2) Which of the following characteristics of stars has the greatest range in values? a) mass b) core temperature c) radius d) surface temperature e) luminosity 3) The light radiated from the Sun's surface reaches Earth in about 8 minutes, but the energy of that light was released by fusion in the solar core about a) a thousand years ago. b) a hundred years ago c) ten years ago. d) one year ago. e) a million years ago. 4) What happens to the surface temperature and luminosity when a protostar radiatively contracts? a) Its surface temperature remains the same and its luminosity decreases. b) Its surface temperature and luminosity remain the same. c) Its surface temperature decreases and its luminosity increases. d) Its surface temperature and luminosity decrease. e) Its surface temperature and luminosity increase. The following questions refer to the H- R diagram below that shows the life track of a 1- solar- mass star, with various stages labeled with Roman numerals. 5) Which stage lasts the longest? a) viii b) I c) iv d) iii e) vi
2 6) In the end, the remaining core of this star will be left behind as a) a supernova. b) a white dwarf made primarily of carbon and oxygen. c) a white dwarf made primarily of silicon and iron. d) a neutron star. e) a black hole. 7) What is the Sun mainly made of? a) hydrogen and oxygen b) oxygen and carbon c) hydrogen and helium d) carbon and nitrogen e) nearly equal portions of all the elements 8) Which of the following comprise the oldest members of the Milky Way? a) red giant stars in spiral arms b) globular clusters c) Cepheid variables d) the Sun and other solar mass stars e) stars 9) How do we know what happens at the event horizon of a black hole? a) Astronomers have analyzed the light from matter within the event horizon of many black holes. b) Astronomers have detected X rays from accretion disks around black holes. c) Astronomers have sent spacecraft through the event horizon of a nearby black hole. d) Physicists have created miniature black holes in the lab. e) We don't know for sure: we only know what to expect based on the predictions of general relativity. 10) What is an astronomical unit? a) any basic unit used in astronomy b) the average speed of the earth around the Sun c) the diameter of the earth's orbit around the Sun d) the average distance from the earth to the Sun e) the length of time it takes the earth to revolve around the Sun 11) What do we mean by the singularity of a black hole? a) It is the center of the black hole, a place of infinite density where the known laws of physics cannot describe the conditions. b) An object can become a black hole only once, and a black hole cannot evolve into anything else. c) There are no binary black holes each one is isolated. d) It is the "point of no return" of the black hole; anything closer than this point will not be able to escape the gravitational force of the black hole. e) It is the edge of the black hole, where one could leave the observable universe 12) On a Hertzsprung- Russell diagram, where would we find white dwarfs? a) upper left b) lower right c) lower left d) upper right
3 13) Cluster ages can be determined from a) main sequence fitting. b) pulsating variable stars. c) visual binaries. d) main sequence turnoff. e) spectroscopic binaries. 14) The spectral sequence sorts stars according to a) radius. b) mass. c) luminosity. d) surface temperature. e) core temperature. 15) On a Hertzsprung- Russell diagram, where on the main sequence would we find stars that have the greatest mass? a) upper right b) lower left c) lower right d) upper left 16) What is nuclear fusion? a) an explosion caused by putting together two volatile chemicals b) a process that only occurs in bombs c) the process of splitting nuclei to produce energy d) the process of combining lightweight nuclei to make heavier nuclei e) the process of turning matter into pure energy 17) According to the universal law of gravitation, if you triple the distance between two objects, then the gravitational force between them will a) decrease by a factor of 9. b) decrease by a factor of 6. c) decrease by a factor of 3. d) increase by a factor of 3. e) increase by a factor of 9. 18) If the moon was new a week ago, what would its phase be now? a) first quarter d) waxing gibbous b) full e) waning crescent c) third quarter 19) If the Moon rises at sunset, what is its phase a) Full b) 1st quarter c) 3rd quarter d) New e) Waning gibbous 20) The length of the Moon's rotation period a) is equal to its orbit period due to the tidal effect of the Earth. b) is gradually decreasing due to tidal drag from the Earth. c) has not changed since the Moon formed. d) is about 24 hours long. e) will eventually be equal to a Solar year.
4 21) In following the Main Sequence on the H- R diagram in the direction of increasing temperature, one is also following a sequence of a) increasing mass d) decreasing stellar diameter b) decreasing mass e) increasing age c) decreasing luminosity 22) Einstein concluded that mass a) causes space to curve b) increases the speed of light c) has no effect on light d) decreases as you go faster e) has no relationship with energy 23) One major success of the Big Bang Theory for the origin of the universe is that it predicted the a) cosmic background radiation d) spin of spiral galaxies b) existence of galaxies e) blueshifts of quasars c) amount of iron atoms in the universe 24) In order for a solar eclipse to occur, the Moon must be a. near new Moon. b. near first or last quarter. c. high in the sky. d. near full Moon. e. in a retrograde loop. 25) The fact that the escape velocity from the Moon is less than that from the Earth is due primarily to a. the Moon's distance from the Earth. b. the smaller mass (81 times less than the Earth's mass). c. the smaller radius (about one- fourth the Earth's radius). d. the higher temperature of the Moon. e. the Moon being alternately closer and farther from the Sun than the Earth as it orbits the Earth each month. 26) What single property of a star most determines its evolution (life cycle)? a) A) mass d) D) radius b) B) chemical composition e) E) surface temperature c) C) luminosity 27) What is the physical significance of the constellations, including the 12 signs or constellations of the zodiac? a) none, they are just random projections of stars onto the celestial sphere. b) your future is determined by which constellation the sun was in when you were born. c) the stars that compose the constellations are gravitationally bound. d) each constellation always has a planet in it. e) you can see all the constellations from all locations on Earth.