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120 Cards in this Set
- Front
- Back
- 3rd side (hint)
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The stars of a constellation are all close together in three-dimensional space.
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False
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True/False
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The sidereal day is determined by Earth's rotation with respect to the stars.
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True
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True/False
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Only people in the Moon's umbral shadow can see a total solar eclipse
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True
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True/False
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There is a solar eclipse of some kind every new moon.
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False
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True/False
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According to Kepler's Laws, the planets move in circular orbits.
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False
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True/False
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A planet will speed up as it approaches the sun.
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True
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True/False
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Kepler's third law allows us to find the average distance to a planet from observing its period of rotation on its axis
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False
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True/False
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In blackbody radiation, the energy is radiated uniformly in every region of the spectrum so the radiation body appears black in color.
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False
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True/False
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According to Wien's law, the hotter the star, the redder its color
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False
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True/False
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In the Doppler effect, a red shift of spectral lines shows that the source is receding from us.
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True
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True/False
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That Polaris will not always be the North Polar Star is due to
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B. precession of the Earth's axis
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A. the sidereal day being shorter than the solar day
B. precession of the Earth's axis C. the tilt of the Earth's axis upon the ecliptic D. Polaris's parallax E. retrograde motion |
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While watching a star, you see it moves 15 degrees across the sky. How long have you been watching it?
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A. 1 hour
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A. 1 hour
B. 3 hours C. 15 minutes D. 1.5 hours E. 1.5 minutes |
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You note that a particular star is directly overhead. It will be directly overhead again in
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C. 23 hours 56 minutes
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A. 1 hour
B. 12 hours C. 23 hours 56 minutes D. 24 hours 4 minutes E. 1 year |
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The fact that the Earth has moved along its orbit around the Sun in the time it took to rotate once about its axis is the reason for
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C. the difference between solar and sidereal day
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A. seasons
B. precession C. the difference between solar and sidereal day D. Earth's 23.5 degree tilt E. the position of the celestial equator |
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When the Moon is directly between Earth and the Sun, its phase is
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D. new
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A. full
B. waxing or waning crescent C. first of third quarter D. new E. waxing of waning gibbous |
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What will occur when the full moon is on the ecliptic
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A. a total lunar eclipse
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A. a total lunar eclipse
B. a total solar eclipse C. a partial solar eclipse D. an annular lunar eclipse E. a partial solar eclipse but only if the moon is at perigee |
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The conditions needed to produce a solar eclipse are a
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D. new moon on the ecliptic
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A. new Moon above the ecliptic
B. full Moon on the ecliptic C. full Moon on the Celestial Equator D. new Moon on the ecliptic E. first or third quarter Moon on the ecliptic |
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An annular solar eclipse may occur when
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E. the moon is farthest from Earth (apogee)
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A. the Moon is closest to the Earth (perigee)
B. the Moon is in its gibbous phase C. Earth is closest to the sun (perihelion) D. Earth is farthest from the sun (aphelion E. the Moon is farthest from Earth (apogee) |
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If Scorpius is now prominent in the summer sky, in 13,000 years it will be best seen
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C. in the winter
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A. in the same season
B. in the autumn C. in the winter D. in the spring E. it will not be visible at all in the northern hemisphere |
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The star Wolf 1061 has a parallax of 2.34 arcseconds, while the star Ross 652 has a parallax of 1.70 arcseconds. What can you correctly conclude?
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E. Wolf 1061 must be closer to Earth
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A. both stars are outside the Milky Way galaxy
B. Wolf 1061 must be brighter than Ross 652 C. Wolf 1061 must be larger than Ross 652 D. Ross 652 must be closer to Earth E. Wolf 1061 must be closer to Earth |
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Copernicus' heliocentric theory explains the fact that
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C. Venus retrogrades when it overtakes us at inferior conjunction
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A. planetary orbits are elliptical in shape.
B. the sun lies at one focus of an ellipse. C. Venus retrogrades when it overtakes us at inferior conjunction D. all planets orbit roughly in the same plane E. Venus will retrograde when it is closest to the Sun |
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According to the Copernican Model, the retrograde motion for Mars will occur
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E. when Earth overtakes Mars and passes between Mars and the Sun
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A. when Mars laps the Earth and passes between us and the Sun
B. when Mars lies on the far side of the Sun. C. when Mars lies exactly 90 degrees east or West of the Sun D. when Mars reverses its direction as it moves along its inner epicycle E. when Earth overtakes Mars and passes between Mars and the Sun |
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Which of these observations of Galileo refuted the Ptolemaic model
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B. the complete cycle of Venus' phases
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A. the craters on the Moon
B. the complete cycle of Venus' phases C. the visibility of many stars with the telescope D. the revolution of Jupiter's moons around it. E. the rotation of sunspots across the solar surface |
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Kepler's first law worked, where Copernicus' original heliocentric model failed, because Kepler described the orbits as
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C. elliptical, not circular
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A. around the Sun, not the Earth
B. being retrograde C. elliptical, not circular D. due to gravity E. much larger than Copernicus had envisioned |
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A planet whose distance from the Sun is 3 AU would have an orbital period of how many Earth-years?
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B. √27
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A. 3
B. √27 C. √3 D. 9 E. 1/3 |
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If the distance between the two asteroids is doubled, the gravitational force they exert on each other will
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C. be one fourth as great
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A. also be doubled.
B. be half as great. C. be one fourth as great. D. be four times greater E. stay the same |
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Which of the following properties of a star cannot be revealed by spectroscopy alone?
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D. diameter
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A. surface temperature
B. chemical composition C. line of sight motion D. diameter E. none of the above |
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Star 1 has a surface temperature twice as high as that of star 2. Which statement is true?
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B. star 1 appears bluer than star 2
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A. star 1 appears redder than star 2
B. star 1 appears bluer than star 2 C. star 1 rotates twice as fast as star 2 D. star 1 has twice as many spectral lines as star 2 E. star 1 emits twice as much energy as star 2 |
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If a wave's frequency doubles, its wavelength
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B. is halved
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A. is also doubled
B. is halved C. is unchanged, as c is constant D. is now four times longer E. it depends on the altitude |
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If a photon's frequency is doubled
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C. its energy is also doubled
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A. its wavelength is also doubled
B. its speed is halved C. its energy is also doubled D. its energy is unchanged E. its temperature is halved |
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What is true of a blackbody?
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C. Its energy peaks at a wavelength determined by its temperature.
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A. It appears black to us, regardless of its temperature.
B. Its energy is not a continuum. C. Its energy peaks at a wavelength determined by its temperature. D. If its temperature doubled, the peak in its curve would be doubled in wavelength E. It emits energy only at certain specific frequencies |
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The total energy radiated by a blackbody depends on
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A. the fourth power of its temperature
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A. the fourth power of its temperature
B. the square of its temperature C. the square root of its temperature D. the cube of its temperature E. its chemical composition |
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The Sun's observed spectrum is
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D. a continuum with black absorption lines.
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A. a continuum with no lines as shown by the rainbow.
B. a continuum with bright emission lines C. only absorption lines on a black background D. a continuum with black absorption lines. E. only emission lines on a black background |
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The number of lines in a star's spectrum
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D. is in general much larger than the number of chemical elements present on the star's surface
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A. coincides with the number of chemical elements present on the star's surface
B. coincides with the number of chemical elements present throughout the star's volume C. is proportional to the star's rotational speed D. is in general much larger than the number of chemical elements present on the star's surface E. is proportional to the star's temperature |
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Doubling the temperature of a blackbody will increase its emitted energy by
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E. 16 times more
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A. 1.5 times more
B. 2 times more C. 4 times more D. 10 times more E. 16 times more |
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A jar filled with hydrogen and helium is placed directly in front of a second jar filed with air. Using a spectroscope to look at the jar containing air through the one containing H and He you observe dark spectral lines. The jar closer to you contains
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D. cooler gases
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A. opaque gases
B. gases at higher pressure and temperature. C. hotter gases D. cooler gases E. gases at higher pressure |
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When an electron moves from a lower to a higher energy state, a photo is
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C. absorbed
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A. emitted
B. transformed into another photon with higher energy C. absorbed D. captured into an orbit surrounding the nucleus E. exchanged with another electron |
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If the laboratory wavelength of a certain line is 600 nm, but we observe it in the spectrum of a star as 594 nm, then
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A. the source is approaching us
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A. the source is approaching us.
B. the source is getting cooler C. the source is rotating faster D. the source is receding from us E. some of the radiation is absorbed by our atmosphere |
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In a hydrogen atom, a transition from the 2nd to the 1st excited state will produce
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B. an emission line
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A. a decrease in temperature
B. an emission line C. an absorption line D. a potential collision between the electron and the nucleus E. two separate emission lines |
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The observed spectral liens of a star are all shifted towards the red end of the spectrum. Which statement is true?
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B. This is an example of the Doppler effect
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A. This is an example of the photoelectric effect
B. This is an example of the Doppler effect C. The second law of Kirchhoff explains this. D. The star is not rotating. E. The star has a radial velocity towards us |
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A seismograph could register P but not S waves from an epicenter on the opposite side of the Earth
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True
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True/False
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There is no evidence of plate tectonics on the Moon today
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True
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True/False
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Due to is larger mass, the Sun's gravitational effect on Earth's tides is greater than the Moon's
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False
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True/False
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Neap tides occur at first and third quarter phases of the Moon
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True
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True/False
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The Moon keeps one side facing the Earth because it does not rotate on its axis
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False
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True/False
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Venus' atmosphere is denser than Earth's
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True
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True/False
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Jovian planets exhibit differential rotation
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True
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True/False
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Jupiter's atmosphere looks uniform and calm, with no visible detail
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False
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True/False
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Saturn puts back into space more energy than it receives from the Sun
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True
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True/False
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Triton and Pluto both probably originated in the Kuiper Belt
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True
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True/False
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What is true about solar system densities?
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A. The denser planets lie closer to the sun
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A. The denser planets lie closer to the sun
B. In differentiated planets, the denser materials lie near their surfaces C. Asteroids and comets all have about the same density D. Saturn has the same density as water E. Planetary density increases with increasing distance from the Sun |
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If Earth had no Moon, then tides would
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C. still occur due to the Sun's influence but be weaker
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A. not occur
B. occur more often and with more intensity C. still occur due to the Sun's influence but be weaker D. occur with the same frequency and lower strength E. occur at random times |
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At what phase would you expect to find the most intense tides?
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D. both new and full Moons
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A. new Moon
B. first and third quarter C. full Moon D. both new and full Moons E. Moon phases are not affecting the tides |
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What is true of the Moon's orbital and rotational periods?
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D. they are equal
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A. the rotational period is longer.
B. the orbital period is longer C. the rotational period varies with the Moon's phase D. they are equal E. the orbital period is greatest at full Moon |
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The greenhouse effect on Earth is caused by
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C. the ground reemitting at a longer wavelength part of the solar radiation it absorbs
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A. the solar wind penetrating Earth's magnetosphere
B. convection currents in the troposphere C. the ground reemitting at a longer wavelength part of the solar radiation it absorbs D. exclusively the burning of fossil fuels E. plate tectonics |
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Without the greenhouse effect in our atmosphere,
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B. the Earth's average temperature would be forbiddingly cold
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A. we would not have to worry about any ecological problems.
B. the Earth's average temperature would be forbiddingly cold. C. the amount of nitrogen and oxygen would be much less D. the ice in our poles would have melted long ago E. the whole Earth would be completely submerged. |
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The existence of convection currents in a planet's atmosphere requires that
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A. the temperature decrease with altitude.
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A. the temperature decrease with altitude
B. the temperature be sufficiently elevated C. the density decrease with altitude D. The planet rotate sufficiently rapidly E. The planet be geologically active |
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The average rate of surface erosion on the Moon is far less than here because
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C. the Moon lacks wind, liquid water and an atmosphere
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A. the crust of the Moon is much harder than the Earth's crust.
B. the Moon is much younger than the Earth C. the Moon lacks wind, liquid water and an atmosphere D. the Moon's magnetic field protects it from the solar wind better than ours does E. the Moon's gravity is far weaker than Earth's |
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On the lunar surface temperature excursions are far more extreme than on Earth because
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B. the Moon lacks an atmosphere
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A. the moon's gravity is only a sixth of Earth's.
B. the Moon lacks an atmosphere. C. the Moon lacks the mitigating effect of oceans D. the Moon rotates too slowly E. the Moon has no magnetic field. |
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We determine the structure of the Earth's core using
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D. seismic wave data (P + S waves)
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A. deep mine shafts
B. satellite imaging C. radar and sonar D. seismic wave data E. magnetic resonance imaging |
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In noting that Earth is "differentiated" we mean that
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A. the density that varies as you descend downward towards its core
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A. the density varies as you descend downward towards its core
B. the Earth is very different from any other planet we study C. the Earth's magnetic field varies at different locations on the globe. D. the Earth's surface displays a wide variety of geological features E. the radioactive heating in the core is increasing with time. |
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The presence of a magnetic field is a good indication that
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C. the Earth has a large amount of swirling molten nickel and iron in its outer core.
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A. the dense earth is made chiefly of iron and nickel
B. the Earth has a huge, nickel-iron meteorite buried under its surface C. the Earth has a large amount of swirling molten nick and iron in its outer core D. the Earth's core is filled with radioactive material E. the Earth's core had time to freeze out solid into a bar magnet |
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How does Mercury's rotation relate to the Sun?
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C. Its rotation rate is 2/3 as long as its year, due to tidal resonances with the Sun
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A. It always keeps one face tidally locked toward the Sun, as our Moon does with Earth.
B. Its year is much shorter than Earth's C. Its rotation rate is 2/3 as long as its year, due to tidal resonances with the Sun. D. Mercury's rotation is retrograde E. It does not spin at all, being stopped by the solar tidal forces |
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Venus' rotation
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E. is retrograde
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A. is the fastest of the terrestrial planets
B. is counterclockwise, like the other planets C. axis is highly tilted to the orbital plane, causing large seasonal changes D. is tidally locked to the Sun E. is retrograde |
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How were Mercury's and Venus's rotation periods determined?
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C. by bouncing radar waves off their surface and measuring Doppler shifts
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A. by looking at surface features with a telescope
B. by computer simulations C. by bouncing radar waves off their surface and measuring Doppler shifts D. using Kepler's third law E. none of the above |
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The scarps on Mercury were probably caused by
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D. the crust cooling and shrinking
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A. tectonic activity
B. meteorite bombardment C. a tidal bulge D. the crust cooling and shrinking E. volcanism |
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The presence of a Mercurian magnetic field is somewhat surprising because
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C. theory predicted that Mercury was spinning too slowly for one
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A. Mercury is low in iron
B. Mercury is too close to the Sun C. theory predicted that Mercury was spinning too slowly for one D. Mercury has no satellites E. Mercury is too hot for its interior to have differentiated |
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The torrid surface temperatures on Venus are the consequence of
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D. a runaway greenhouse effect
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A. Venus' proximity to the Sun
B. intense volcanic activity C. the planet's exceedingly slow rotation D. a runaway greenhouse effect E. powerful convection currents in the atmosphere |
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Small deviations in a planet's orbital motion
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D. imply the gravitational influence of a nearby massive body
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A. show we don't fully understand gravitational forces yet
B. indicate the presence of an extensive atmosphere C. indicate the presence of a powerful magnetic field D. imply the gravitational influence of a nearby massive body E. show the planet's orbit is not stable |
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Jupiter and the other Jovian planets are noticeably oblate because
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C. they are mostly fluid bodies that are spinning rapidly
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A. they all have strong magnetic fields that deform their shape
B. their powerful gravity acts more strongly on the poles than at the equator C. they are mostly fluid bodies that are spinning rapidly D. they are tidally distorted by the pulls of their satellite systems E. all of the above are correct |
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Which of these is true about the seasons of Uranus?
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B. the strange axial tilt produces extreme seasonal variations
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A. with an axial tilt of 29 degrees, they are not that different from our own.
B. the strange axial tilt produces extreme seasonal variations C. at the Uranian equator the sun would never set D. at the Uranian equator, the sun would always pass overhead every 16 hours E. Uranus is too far from the Sun to have seasons |
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The reason the Jovian planets lost very little of their original atmosphere is due to their
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D. large mass and low surface temperature
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A. rapid rotation
B. strong magnetic fields C. ring systems D. large mass and low surface temperature E. many moons |
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The reason why Jovian planets are believed to possess rocky cores is because
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C. otherwise they would be more oblate than they are
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A. they have strong magnetic fields
B. they are very massive C. otherwise they would be more oblate than they are D. they emit more heat than they receive from the Sun E. otherwise they would become stars like the Sun |
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What is thought to cause Io's volcanism?
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C. tidal stresses from both Jupiter and Europa
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A. Jupiter's magnetosphere
B. Jupiter's gravity C. Tidal stresses from both Jupiter and Europa D. radioactive decay of uranium in its dense core E. Meteoritic bombardment |
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Europa is of great interest to planetary scientists because
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A. is likely to have liquid water under a thick icy layer
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A. is likely to have liquid water under a thick icy layer
B. its orbit is unique in the solar system C. is destined to be torn apart by Jupiter's tidal forces D. it has a dense atmosphere E. is geologically very active |
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What likely enabled Titan to retain a dense atmosphere?
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B. it's extremely low surface temperatures
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A. The influence of Saturn's rings.
B. Its extremely low surface temperatures C. The fact that its atmosphere is continually replenished by volcanic activity D. the absence of other large moons orbiting Saturn E. the intense greenhouse effect produced by methane |
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The Cassini Division is a gap in Saturn's rings caused by
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D. gravitational interaction with Mimas
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A. Saturn's excess heat
B. two shepherding moons C. Saturn's magnetic field D. gravitational interaction with Mimas E. the icy ring particles melting |
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Inside a planet's Roche limit
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A. large moons are likely to be torn apart by the planet's tidal forces
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A. large moons are likely to be torn apart by the planet's tidal forces
B. is where large moons form C. ring systems cannot exist D. there is a gap in a planet's magnetic field E. hydrogen can only exist in its liquid metallic form |
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Triton's ultimate fate will be
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E. to be torn apart by tidal forces as it spirals inward towards Neptune
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A. to collide with Proteus, a smaller Neptunian moon
B. to become tidally locked with Neptune C. to collide with Neptune D. to be ejected from the solar system E. to be torn apart by tidal forces as it spirals inward towards Neptune |
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Pluto has been demoted from the status of a major planet primarily because
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A. it has characteristics similar to other discovered Kuiper Belt objects
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A. it has characteristics similar to other discovered Kuiper Belt objects
B. it does not have a magnetic field C. it does not have satellites D. it does not have an atmosphere E. its orbit around the Sun is retrograde |
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Granulation is the most direct evidence of solar convection
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True
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True/False
|
|
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During the nuclear fusion process, mass is converted into energy
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True
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True/False
|
|
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A star twice as luminous as the Sun must be twice as hot
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False
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True/False
|
|
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The most favorable environment for stellar formation is given by hot and bright nebulae
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False
|
True/False
|
|
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The predominant color of emission nebulae is blue
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False
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True/False
|
|
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21 cm radiation is a result of an electron in hydrogen flipping its spin direction
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True
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True/False
|
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Gold is race since the only time it can be formed is during the core collapse of a supernova
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True
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True/False
|
|
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Novae and supernovae are essentially the same phenomenon
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False
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True/False
|
|
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A neutron star is what remains after a Type II supernova explosion has destroyed the rest of the star
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True
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True/False
|
|
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The "pulse" from a pulsar is due to the rapidly expanding and contracting outer shell of the star
|
False
|
True/False
|
|
|
What is the meaning of the solar constant?
|
D. the amount of energy Earth receives per unit area and per unit time
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A. the regularity of the 11-year sunspot cycle
B. the fact that features on the Sun appear to never change C. the stability of the Sun's luminosity for as long as life has existed on Earth D. the amount of energy Earth receives per unit area and per unit time E. the fact that the amount of hydrogen turning into helium in the core is fixed |
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The outward pressure of hot gas in the Sun
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A. is balanced by the inward gravitational force
|
A. is balanced by the inward gravitational force
B. is increasing the Sun's diameter C. is cooling the photosphere D. is responsible for variations in the sunspot cycle E. weaken the magnetic field |
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What two energy transport mechanisms are found in the Sun?
|
B. radiation, convection
|
A. convection, conduction
B. radiation, convection C. conduction, radiation D. nuclear fusion, radiation E. nuclear fission, convection |
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What natural barrier must be overcome for two protons to collide and fuse together?
|
C. electrostatic repulsion
|
A. gravity
B. dark energy C. electrostatic repulsion D. nuclear energy E. degenerate electron pressure |
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Sunspots are dark splotches on the Sun. What statement is true?
|
C. They are extremely hot, but cooler than the surrounding areas of the photosphere
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A. They are hotter than the surrounding areas of the photosphere
B. they are extremely cold objects, as cold as Pluto C. They are extremely hot, but cooler than the surrounding areas of the photosphere D. They are solid bodies floating on the surface of the Sun E. They are not associated with magnetic field lines |
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Today, the primary source of the Sun's energy is
|
D. the nuclear force fusing hydrogen into helium
|
A. oxidation of carbon in the core
B. gravitational collapse of the helium towards the core C. dark energy D. the nuclear force fusing hydrogen into helium E. the nuclear force creating energy from uranium fission |
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A star is 10 parsecs from Earth. Which statement is true?
|
E. The star's parallax is 0.1 arcseconds
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A. The star's parallax is 10 arcseconds
B. The star is in a different galaxy C. The star's luminosity cannot be determined D. The star's proper motion cannot be determined E. The star's parallax is 0.1 arcseconds |
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What can be said with certainty about a red star and a blue star?
|
B. The blue star is hotter than the red star
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A. The red star is more massive than the blue star.
B. The blue star is hotter than the red star C. The red star has a greater Doppler shift than the blue star D. The blue star has a greater proper motion than the red star E. The red star is closer to Earth than the blue star |
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On an H-R diagram, one plots
|
C. luminosity versus temperature
|
A. temperature versus mass
B. radius versus luminosity C. luminosity versus temperature D. radius versus mass E. distance versus luminosity |
|
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On an H-R diagram, the Sun lies
|
E. at about the middle of the main sequence
|
A. at the top left
B. at the top right C. at the bottom left D. at the top of the main sequence E. at about the middle of the main sequence |
|
|
A star near the lower right of the H-R diagram is likely to be
|
C. red with low luminosity
|
A. red, with high luminosity
B. blue, with high luminosity C. red, with low luminosity D. hot, bright and very large e. yellow, with luminosity similar to our Sun's |
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Stars A and B appear equally bright but A is more luminous than B
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D. A is farther than B
|
A. A is larger than B
B. A is younger than B C. A is hotter than B D. A is farther than B E. A is denser than B |
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|
The Doppler shift is used to find
|
B. spectroscopic binaries
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A. eclipsing binaries
B. spectroscopic binaries C. visual binaries D. merging binaries E. collapsing binaries |
|
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What effect do clouds of dust have on light passing through them?
|
B. They dim and redden the light of more distant stars
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A. The light that passes through them is blue-shifted due to the cloud's approach
B. They dim and redden the light of more distant stars C. Even a little dust can completely block all light D. The dust's motion causes the light of stars beyond to twinkle E. The clouds' motion causes all light to be red-shifted as it passes through them |
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What two things are needed to create an emission nebula?
|
D. hot stars and interstellar gas, particularly hydrogen
|
A. interstellar gas and dust
B. hydrogen fusion and helium ionization C. cool stars and much interstellar dust D. hot stars and interstellar gas, particularly hydrogen E. hydrogen gas and carbon dust |
|
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The most favorable environment for stellar birth is
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C. a dark nebula
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A. a thin emission nebula
B. a cool reflection nebula C. a dark nebula D. a globular cluster E. an open cluster |
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|
With respect to a globular cluster, an open cluster is
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C. populated by younger, hotter, fewer stars
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A. more easily penetrated by radio waves
B. populated by older dimmer and more isolated stars C. populated by younger, hotter, fewer stars D. populated by fewer emission nebulae E. generally closer to Earth |
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Why are star clusters ideal to study stellar evolution?
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C. Their stars are all about the same age and distance from us
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A. The combined light of all the stars makes them easier to see.
B. Like our Sun, they lie in the plane of the Milky Way C. Their stars are all about the same age and distance from us D. Their stars are all about the same mass and temperature E. their stars are all the same stage in evolution |
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A star will spend most of its life
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B. on the main sequence
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A. as a protostar
B. on the main sequence C. inside its planetary nebula D. as a red giant E. in a sustained helium flash lasting billions of years |
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A solar mass star will evolve off the main sequence when
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D. hydrogen has been completely converted into helium in the core
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A. it completely runs out of hydrogen
B. it expels a planetary nebula to cool off and release radiation C. it explodes in a violent nova D. hydrogen has been completely converted into helium in the core E. it loses all its neutrons, so fusion must cease |
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An iron core cannot counterbalance a giant star's gravity because
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E. iron cannot fuse into other elements and produce additional energy in fusion
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A. iron is heavy, and settles to the Earth's core
B. iron decays rapidly into lead C. iron is too dense and produces too much gravity D. iron produces strong magnetic fields E. iron cannot fuse into other elements and produce additional energy in fusion |
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The heaviest nuclei of all are formed
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E. in a type II core collapse supernova event
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A. in the horizontal branch
B. in dense white dwarfs C. during nova explosions D. in the ejection of matter in the planetary nebula E. in a type II core collapse supernova event |
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What can you conclude about a Type I supernova?
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A. It was originally a low-mass star
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A. It was originally a low-mass star
B. It was originally a high-mass star C. Its spectrum will show large amounts of hydrogen D. Its core was mostly iron E. The star never reached Chandrasekhar limit |
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Which of these does not depend on a close binary system to occur?
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C. a type II (core collapse) supernova
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A. a nova
B. a type I supernova C. a type II supernova D. all of these need mass transfer to occur E. none of these depend on mass transfer |
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Two important properties of young neutron stars are
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C. extremely rapid rotation and a strong magnetic field
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A. extremely slow rotation and a strong magnetic field
B. extremely rapid rotation and a weak magnetic field C. extremely rapid rotation and a strong magnetic field D. no rotation and a weak magnetic field E. no rotation and no magnetic field |
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In the lighthouse model of a pulsar
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C. if the beam sweeps across us, we will detect a pulse of radiation
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A. the star literally turns on and off like a lighthouse beacon,
B. all pulsars must have their poles pointing permanently towards us. C. if the beam sweeps across us, we will detect a pulse of radiation D. the period of pulsation must speed up as the neutron star continues collapsing E. the period of pulsation slows down due to the drag of the remnant on its field |
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You would expect millisecond pulsars to be
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A. part of a binary system
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A. part of a binary system
B. isolated in space C. rotating slowly D. most common in open clusters E. collapsing rapidly |
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What would happen if more mass was added to a 1.4 solar mass neutron star?
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E. It would blow off mass as an X-ray burster
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A. It would erupt as a Type I supernova
B. It would eventually become a black hole, via a hypernova explosion C. It would grow larger, temporarily becoming a red giant again D. All of its protons and electrons would turn into neutrons E. It would blow off mass as an X-ray burster |
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If the Sun were replaced by a one solar mass black hole
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B. we would still orbit it in a period of one year
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A. all terrestrial planets would fall into it immediately
B. we would still orbit it in a period of one year C. we would immediately escape into deep space, driven out by its radiation D. our clocks would all stop E. life here would be unchanged. |
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Which statement about black holes is true?
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A. Their escape velocity is greater than the speed of light
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A. Their escape velocity is greater than the speed of light.
B. They form from low mass stars C. They form from an event horizon at ten times the Schwarzschild radius D. Their main sequence mass was 1000 solar masses E. Their event horizon is a solid surface boundary |
