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50 Cards in this Set
- Front
- Back
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Which of the following is not a line of evidence supporting the hypothesis that our Moon formed as a result of a giant impact |
The Pacific ocean appears to be a large crater- probably the one made by the giant impact. |
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Which of the following best explains why nuclear fusion requires bringing nuclei extremely close together? |
Nuclei normally repel because they are all positively charged and can be made to stick only when briught close enough for the strong force to take hold. |
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Why are there fewer large impact craters on the Earths seafloor than on the continents? |
Seafloor crust is younger than continental crust, so it has had less time in which to suffer impacts. |
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Does Venus have auroras its poles, like the Earth? Why or why not? |
No, because it lacks a global magnetic field. |
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The choices below describe four hypothetical planets. Which one would you expect to have the most features of erosion? (Assume the planets orbit a star just like the Sun and that theu are all the same age as the planets in our solar system) |
Size: same as Venus. Distance from Sun: same as Mars. Rotation rate: once every 25hrs |
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Whixh characteristic of Earth explains why we have an ultraviolet-absorbing stratosphere? |
The existence of photosynthetic life |
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Which of the following gases is not a significant ingredient of the jovian planet atomospheres ? |
Carbon dioxide |
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Gaps in the asteroid belt (often called Kirkwood gaps) are caused by _______. |
Orbital resonances with Jupiter |
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Supose there were no solar wind. How would the appearance of a comet in our inner solar system be different? |
It would have onky one tail instead of two. |
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According to our theory of solar system formation, which law best explains why the solar nebula spun faster as it shrank in size? |
The law of conversation of angular momentum |
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According to our present theory of solar system formation, which of the folowing objects now reside quite far from the place where they formed originally? |
Oort clous comets |
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All the statements below are true. Which one gives the primary reason why the surface of Venus today is some 450 C hotter than the surface of Earth? |
Venus had a much stronger greenhouse effect than Earth. |
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If we could put all the asteroids together, their total mass would be _______. |
Much less than the mass of any terrestrial planet. |
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Recent evidence suggests that Mars once had a global magnetic field. Assuming this is true, which of the following could explain why Mars today lacks a global magnetic field like that of Earth? |
Mars interior has cooled so much its molten core layer no longer undergoes convection. |
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Many scientists suspect that Venus has a stronger and thicker lithosphere than Earth. If this is true, which of the following could explain it ? |
The high surface temperature that has "baked out" all the liquid water from Venus's crust and mantle. |
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The star Alpha Centauri A is the same type of star as the Sun, but its luminosity is about 1.6 times that of the Sun. What can we conclude? |
Alpha Centauri A fuses hydrogen into helium in its core at a higher rate than our Sun. |
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Why is thermal escape of atmospheric gas much easier from the Moon than from Earth? |
Because the Moon's gravity is so much weaker than Earth's. |
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Suppose we discover a new comet on an orbit that brings it closer to the Sun then Mercury every 125 years. What can we conclude? |
It has been on its current orbit for only a very short time compares to the age of our solar system. |
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Suppose that Earth's ice caps melted, but everything else about the Earths surface and atomosphere stayed the same. What would happen to Earth's average surface temperature? |
The surface temperature would increase |
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When is/was gravitational contraction an important energy generation mechanism for the Sun? |
It was important when the Sun was forming from a shrinking interstellar cloud of gas. |
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According to our present theory of solar system formation, which of the following best explains why the solar nebula ended up with a disk shape as it collapsed? |
It flattened as a natural consequence of collisions between particles in the nebula. |
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According to our theory of solar system formation, why did Uranus and Neptune end up to be much lwas massive than Jupiter and Saturn? |
Particles in the solar nebula were more spread out at greater distances, so that accretion took longer and there was less time to pull in gas before the solar wind cleares the nebula. |
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All the following statements about Venus are true. Which one offers evidence of a global repaving about a billion years ago? |
Venus has relatively few impact craters and these craters are distributed fairly evenly over the entire planet. |
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A comouter accessory salesman attempts to convince you ro ourchase a "solar neutrino" shield for your new computer. (Its even "on sale" !) Why do you turn down this excellent offer? |
Neutrinos rarely, if ever, interact with your computer. |
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Which of the following best describes how the greenhouse effect works? |
A planets surface absorbs visible sunlight and returns this absorbed energy to space as infrared light. Greenhouse gases slow the escape of this infrared radiation, which thereby heats the lower atomosphere. |
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Suppose that large jovian planets had never formed in our solar system. Which of the following would most likely be true? |
Neither the asteroid belt nor Oort cloud would exist. |
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Why is Earth's continental crust lower in density than seafloor crust |
Continental crust is made as the lowest density seafloor crusy melts and erupts to the surface near subduction zones. |
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Uranus and Neptune have methane clouds but jupiter and saturn do not. Which factor explains why? |
Temperatures on Jupiter and Saturn are too high for methane to condense |
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Which of the following statements about Earth's troposphere is not generally true? |
It is the layer of the atmosphere in which ozone absorbs dangerous ultraviolet light from the Sun |
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The astrometric technique looks for planets eith careful measurements of a star's ________. |
Position in the sky |
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All the following statements are true. Which one explains why convection can occur in the troposphere but not in the stratosphere? |
Temperature declines with altitude in the troposphere but increases with altitude in the stratosphere. |
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All the following statements about known extrasolar planets are true. Which one came as a surprise to scientists who expected other solar systems to be like ours. |
Some of the planets orbit their star more closely then Mercury orbits the Sun. |
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Which planet mah have helium rain in its interior, and what does this rain do? |
Saturn, where it generates heat as it falls downward. |
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How is it possible that the moon might have some water ice today |
Ice brought by comet impacts may be frozen in craters near the Moons poles. |
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Which of the following is the best answer to the question, "why does the Sun shine"? |
As the Sun was forming, gravitational contraction increased the Suns temperature until the core beckme hot enough for nuclear fusion, which ever since has generated the heat that mames the Sun shine |
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Which of the following is not a piece of evidence supporting the idea thst Europa may have a subsurface ocean? |
Astronomers have detected small lakes of liquid water on Europas surface. |
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Current evidence suggests that many massive joviam planets orbit at a very close orbital distances to their stars. How do we think these planets ended up on these close orbits ? |
These planets migrated inward after being born on orbits much further from they stars |
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According to our present theory of solar system formation, how did Earth end up with enough water to make oceans ? |
The water was brought to the forming Earth by planetesimals that accreted beyond the orbit of Mars |
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The cores of the terrestrial worlds are made mostly of metal because _____ |
Metals sunk to the centers a long time ago when the interiors were molten throughout |
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To date we've found very few planets orbiting their stars at distances comparable to the distances of the jovian planets in our solar system. Why do astronomers think this is the case? |
We have not yet been searching for planets as such distances for a long enough time |
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Which of the following best why we see horizontal "stripes" in photographs of Jupiter and Saturn? |
The light stripes are regions of high clouds, and the dark stripes are regions where we can see down to deeper clouds |
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Which of the following best describes the geological histories of the moon and mecury? |
Early in their histories, they suffered many impacts and experienced some volcanism and tectonics but they nlw have little geological activity at all |
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You discover an impact crater that is 10kilos across. Which of the following can you conclude? |
It was created by the impact of an object 1 kilo across |
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In general which type of planet woukd youexpect to cause the largest Doppler shift in the spectrum of its star? |
A massive planet that is cllse to its star |
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Which of the following is most unlikely to be found on Titan |
Lakes of liquid water in the warmer equatorial regions |
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What is Plutos moon Charon thought to have in comon with our own moon |
It probably formed as a result of a giant impact |
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Earth had been gradually warming over the oast fre decades. Based on a great deal of evidence, scientist bekieve tha this warming is caused by... |
Human activities that are increasing the concentration of greenhouse gases in Earth's atmosphere |
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Many meteorites appear to have formed very early in the solar systems history. How do these meteorites supoort our theory about how the terrestrial planets formed ? |
The meteorites appearance and composition is just what wed expect if metal and rock condesed and accreted as our theory suggests |
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Suppose Earth were too xool down a little. How would the csrbon dioxide cycle tend to restore temperatures to normal? |
Cooler temps lead to slower formation of carbonate minerals in the ocean so csrbon dioxde released by volcanism builds up in the atmosphere and strengthens the greenhouse effect |
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Which of the following most likely Solaris why Jupiter interior releases so much heat? |
Jupiter is contracting very gradually |
