B. ultraviolet29 a) What determines whether or not a star explodes as a supernova? Explain the events that lead up to the actual explosion. (4 pts.)Fall 2002 Exam IIMULTIPLE CHOICE QUESTIONS (50 pts.)Choose the BEST answer to each of the following questions using what you have learned inASTR 101. Indicate your choice on the scantron. (2 pts. each)1. In the Cygnus X-1 system, the X-rays are explain by astronomers asA. strong radiation emitted by a supergiant star.B. a distant galaxy that has recently been born.C. coming from very hot gas in a black hole’s accretion disk.D. what’s left after a pulsar stopped pulsing.E. matter and antimatter annihilation.2. According to Einstein’s theory of general relativity, the gravitational force results fromA. pressure exerted by radiation.B. interatomic forces between masses.C. curvature of space by mass.D. the expansion of the universe.E. the relative weights of the objects involved.3. The 65 million year old clay layer containing Iridium that is observed all over the Earth iscited as support forA. the formation of the Moon.B. continental drift.C. magnetic reversal.D. a large asteroid impact.E. the presence of an atmosphere rich in oxygen.4. Magnetic fields inhibit the convective flow of energy to the Sun’s photosphere and disrupt thegranulation pattern. This process leads to the formation ofA. prominences.B. sunspots.C. meteorites.D. hydrogen absorption lines.E. hydrogen emission lines.5. Life on Earth chemically depends on which atom that forms long chains with itself leading tocomplex molecules?A. oxygenB. hydrogenC. ironD. nitrogenE. carbon6. Given positions of stars A and B in the spectroscopic binary shown below, which spectrumshowing the H Alpha and H Beta absorption lines would represent the binary star’s spectrum atthis time?Diagram will be given in Discussion Session7. Using the Bohr atomic model representation, which atom has just absorbed a photon?Indicate A or B or C =proton =electronDiagram will be given in discussion session8. Interstellar dust lying between a star and an observer on Earth will cause the star to appearA. dimmer and redder.B. dimmer and bluer.C. brighter and redder.D. brighter and bluer.E. unaffected due to the wavelength of visible light.9. Titan, moon of Saturn, is of interest and will be visited by the Cassini probe that will arrive atSaturn in 2004. What observation of Titan did the earlier Voyager mission make?A. Voyager photographed active volcanoes on Titan's surface.B. Voyager detected a ring around this satellite.C. Voyager noticed a large amount of radio emission from Titan.D. Voyager couldn't photograph Titan's surface due to its orange, hazy atmosphere.E. Voyager's life detection experiments gave inconclusive results.10. The reason that astronomers use the concept of absolute magnitude is toA. make life difficult for ASTR 101 students.B. allow stars to be compared with the effects of differing distances removed.C. allow stars to be compared with the effects of differing masses removed.D. allow stars to be compared with the effects of differing temperatures removed.E. allow stars to be compared with the effects of differing radii removed.11. The Leonid meteor shower occurred Nov. 18-19. The shower meteors seen were originallypart of A. the asteroid belt.B. the Sun.C. one of the rings of Saturn.D. a comet.E. debris surrounding the Moon.12. If a scale model of the Solar System were placed on Byrd Stadium football field here at theUniversity of Maryland, using the same scale, the closest star (other than the Sun) would beA. a few hundred feet away.B. a few miles away.C. a few hundred miles away.D. a few thousand miles away.E. at the Moon’s distance.13. A planetary nebula, like the Ring Nebula shown in class, isA. evidence that planets exist around other stars.B. gas that is about to collapse and form planets.C. a giant molecular cloud that is about to form new stars.D. a very dense cloud with many organic molecules.E. gas ejected by a star, which is becoming a white dwarf.14. If the Earth were struck by a sizeable asteroid (more than 10 km across), it is most likely thatA. our protective atmosphere would cause the asteroid to vaporize.B. the impact would split the Earth into two.C. an environmental crisis would trigger a mass extinction.D. it would make a crater that would exist for billions of years.E. the dinosaurs would return.15. A gigantic solar flare occurred on the Sun this morning. Mrs. Deming was excited and toldher ASTR 101 class to expect (if it is clear)A. a full moon tonight.B. an eclipse.C. a meteor shower.D. an aurora.E. dangerous cosmic rays.16. Emission nebulae, like the North American Nebula, appear red due to emission by hydrogenatomsA. as electrons move from level 2 to level 3.B. as electrons move from level 3 to level 2.C. as the electrons break completely free from the nuclei.D. due to the electrons and protons colliding.E. as fusion begins in the cloud.17. If you were thrown onto the surface of Mars without a spacesuit, what would be your mostlikely cause of death?A. You would be crushed to death by the high atmospheric pressure.B. You would slowly freeze to death.C. You would suffocate and have problems dealing with the low atmospheric pressure.D. Volcanic activity would bury you.E. Hungry martian microbes would eat you.18. At the center of the Crab Nebula supernova remnant in Taurus lies aA. white dwarf.B. planet.C. black hole.D. pulsar.E. protostar.19. Jupiter's ring was first detectedA. by Galileo with his telescope.B. when Voyager flew by Jupiter.C. using a radio telescope.D. using the Hubble Space telescope.E. by amateur astronomers as they watched the comet hit Jupiter.20. The peak or maximum wavelength that you are emitting right lies in which portion of theelectromagnetic spectrum?A. X rayB. ultravioletC. visibleD. infraredE. radio21. The protons and neutrons in a helium nucleus are held together by theA. gravitational force.B. electromagnetic force.C. strong nuclear force.D. chemical force.E. all of the above.22. The classroom demonstration in which a student was placed in the spinning chair withweights was meant to show what happensA. as a neutron star collapses and its rotation speeds up.B. when gravity is balanced by rotation.C. when a fast-spinning object ejects matter into space.D. as weightlessness takes control.E. to stars in a binary system when one explodes.23. Radio waves have _______wavelength and _____photon energy