Quiz
EXAM 3: practice test
Questions in this quiz (30)
1The mass of a star can be determined if
- AYou can measure relative line strenghs in the spectrum
- BThere is line splitting in the spectrum
- CIt is in a binary star system
- DThe Zeeman effect is large enough
2All stars dont EVOLVE in exactly the same way or at exactly the same rate. Stars evolve differently because they are formed with different initial
- Amasses
- Bcompostition
- Cmagnetic fields
- Dgas pressure
3Neutron stars are COMPOSED of _______________.
- Ahydrogen, with some helium
- Bcarbon with some oxygen
- Cdegenerate neutrons, with some heavy elements
- DHelium with some carbon
- Eiron with some lead
4Why do Neutron stars rotate rapidly?
- AThe supernova explosions acts as a rocket to speed up the rotation
- BMagnetic fields act to speed up the rotation of the neutron star
- CAngular momentum is conserved, a neutron star speeds up its rotation as it contracts.
- DNeutron stars form from binary stars, so they naturally have very high rotation rates
5X-rays are emitted strongly from the two best black hole candidates, Cyg X-1 and IMC X-3, X-rays from black homes are expected to be from....
- Aan accretion disk of material around the black hole
- Ba companion star, greatly distorted by the tidal forces
- Cthe high temperature of black hole itself
- Dthe supernova remnant surrounding the black hole
6The event horizon of a black hole
- AIs believed to be a singularity
- BIs the surface of the black hole, similar to the surface of the Earth
- CHas a radius equal to the Schwarzshild radium
- DMarks the boundary where in-falling material starts to emit X-rays
7Whether a star will END its life as a black hole, a neutron star, or a white dwarf depends on its
- AMass
- Bradius
- Crotation rate
- Dsurface temperature
- EComposition
8When might it be possible to detect a black hole?
- AA black holes can be detected if their incredibly strong gravity disrupts stars inside our galaxy
- BBlack holes are only black in the visible part of the spectrum. X-ray and gamma ray energy can escape from inside the event horizon
- CBlack holes are impossible to detect, they give off no electromagnetic energy
- DBlack holes might be detected by the motion of a binary companion
- Eblack holes create quantum strings in space, which provides a convenient route fro interstellar travel. Look for the paths of interstellar spaceships
9Harlow Shapley used globular clusters to show that the
- AMilky way is just one of many island universes
- BSolar system is located far from the center of the milky way
- CUniverse is expanding
- DMIlky way is actually a globular cluster itself
- EMilky way is not much bigger than the Solar System
10Which of the following is a characteristic of the halo of the milky way galaxy?
- ACircular star orbits
- Byoung stars
- Cactive star formation regions
- DHigh metal abundance
- EHigh content of interstellar dust
11One problem in trying to figure out the structure of our Galaxy was that
- AThere is no way to measure the distances greater than about 120 light years.
- BThe galaxy looks uniform in all directions from earth
- CThe positions of stars in the Galaxy change so rapidly that it is difficult to make an accurate picture of any give year.
- Dour view of much of our galaxy is blocked by the comet cloud of the Oort cloud
- EInterstellar dust hides many stars, so we only see nearby stars in our galaxy.
12The distribution of globular clusters in the sky as seen from Earth is
- Ahomogeneous
- Bisotropic
- Cboth homogeneous and isotropic
- Dneither homogeneous nor isotropic
13Why do astronomers use Cepheid variable stars to measure galaxies distances?
- AThe faster they vary, the more distant they are
- Btheir luminosity can be determined from their period of variation
- Cthey obey Hubble's law
- Dthey are the most common type of main-sequence star visible in galaxies
- Ethey all lie in the same spot on the HR diagram
14What observations suggest the mass of a spiral galaxy like our own goes much farther out than its visible disk?
- AThe orbits of the open dusters in the disk
- Bx-ray images of other galaxies disks from Chandra x-ray telescope
- Cthe rotation curve including the outermost portions of the disk of the galaxy
- DRadio maps of spiral arms, since the radio emission can see farther into the galaxy
- EIR observations of distant brown dwarfs which are not seen easily in visible light
15An astronomer living in galaxy 7 billion light years away from here would see
- ASome distant galaxies have redshifts and some have blueshifts
- Bmany more nearby quasars than we see
- Cour galaxy approaching theirs
- Dthe more-or-less same relation between redshift and distance that we see.
- EAll of the above
16Quasars must be small because they
- Ahave high radial velocities
- Bare very luminous
- Chave luminosity that fluctuate rapidly
- DAre surrounded by quasar fuzz
- Eradiate huge amounts of energy
17We conclude that the universe is expanding because
- AWe observe the galaxies getting smaller and smaller every year.
- Bthe proper motions of galaxies suggest they are moving away from a point
- Cwe observe galaxies disappearing from view every year
- Dredshifts of distant galaxies are proportional to the galaxy's distance from us
- Eall of the above
18The blue-shift exhibited by some nearby galaxies lends support to the
- Abig bang model, because those galaxies are expanding towards us
- Blocal group concept because nearby galaxies interact gravitationally
- Cevolution theory because galaxies change color as they evolve
- Doscillating universe theory because some galaxies are moving together already
- Estatic theory because the local universe is apparently not expanding
19To which of the following objects does Hubble's law apply
- Astars in the Milky way
- Ball galaxies
- Cdistant galaxies
- Dnearby stars in the Milky way
- Eall of the above
20We only observe events that happened in the past becasue
- Ait takes time to analyze the data
- Bthe speed of light is finite not infinite
- Cthe universe is very old
- Dour telescopes are not yet large enough
- Ethe light has been red-shifted.
21Imagine that some galaxies have unusually rapid rotating pulsars called sonic pulsars. Suppose that careful research showed that only the galaxies with large redshifts have sonic pulsars. This most likely indicates that
- Aintracluster dust increases pulsar rotation rates
- Breshifting increases pulsar rotation rates
- Csound travels faster than radio emission
- Donly old galaxies have sonic pulsars
- Esonic pulsars existed in the past but not today
22Which is in the correct order of nearest us to farthest away?
- Aquasar Mk141, the crab nebula, the large magellanic cloud
- Bthe crab nebula, quasar Mk141, the large magellanic cloud
- Cthe crab nebula, the large magellanic cloud, quasar Mk141
- Dthe large magellanic cloud, the crab nebula, quasar Mk141
23In which of these would you find more "high metallicity stars"
- Ain a quasar
- Bin a giant elliptical galaxy
- Cin a n active galaxy
- Din a globular cluster
- Ein a nearby spiral galaxy
24No stars can form in elliptical galaxies because those galaxies do not have significant
- Asupernova remnants
- Binterstellar clouds
- Cplanetary nebula
- Dmagnetic fields
- Ehelium
25What can we conclude from the pattern of reshifts and blueshifts of the galaxies that we observe
- Aall galaxies are rotating at approximately equal rates
- Bcosmic rays seem to originate only from the redshifted galaxies
- Calmost as many galaxies are moving towards us as we are moving away from us
- Dthe universe itself is expanding in all directions
- Ealmost all galaxies are moving toward each other, and will eventually collide
26Which is true about quasars? they are
- Athought to represent an active period in the earliest stages of the life of a galaxy
- Btypically the size and absolute brightness of a typical large star
- Cthe brightest stars in the universe
- Dstars in the last stages of their lives when they die in a last outpouring of energy
- Eextremely old galaxies
27How do we determine the distance to quasars?
- Aby measuring their reshift and using the Hubble law
- Bby comparing photographs taken many years apart
- Cby taking a spectrum and using Wien's law
- Dby measuring the Doppler shifts of stars at the edges of the galaxies
- Eby using parallax and the Tully-fisher Law
28Using your knowledge about stars and galaxies, which of the following would you suspect has the largest redshift?
- Aa dwarf elliptical galaxy
- Ba spiral galaxy
- Ca seyfert galaxy
- Da red giant star
- Ea star like the sun
29Which of these galaxies is an elliptical galaxy?
- AAndromeda
- BMilky Way
- CM87
- DLarge Magellanic Cloud
30From the theme song of the television show "The big bang", you could learn correctly that originally " the whole universe was "
- Athe size of a peanut
- Binfinetly dense
- Cin a hot dense state
- Da mathematical improbability
- Ecomposed of hydrogen
Information
- Description
- Stellar evolution, Nebula, Death of low mass stars, High Mass Stellar Evolution, supernova, blackholes, Galaxies, Milky way Galaxy, and Cosmology
- Author
- Alaina Goff
- Language
- English
- Views
- 2
- Tags
- Rating
- No ratings yet Rate this quiz