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[Reading Comprehension]

试题详情

文章:

Line        When asteroids collide, some collisions cause
 an asteroid to spin faster; others slow it down. If
 asteroids are all monoliths—single rocks—undergoing
 random collisions, a graph of their rotation rates
(5)should show a bell-shaped distribution with statistical
 “tails” of very fast and very slow rotators. If asteroids
 are rubble piles, however, the tail representing the
 very fast rotators would be missing, because any
 loose aggregate spinning faster than once every few
(10)hours (depending on the asteroid’s bulk density)
 would fly apart. Researchers have discovered that
 all but five observed asteroids obey a strict limit on
 rate of rotation. The exceptions are all smaller than
 200 meters in diameter, with an abrupt cutoff for
(15)asteroids larger than that.
      The evident conclusion—that asteroids larger than
 200 meters across are multicomponent structures
 or rubble piles—agrees with recent computer modeling
 of collisions, which also finds a transition at that
(20)diameter. A collision can blast a large asteroid to bits,
 but after the collision those bits will usually move
 slower than their mutual escape velocity. Over several
 hours, gravity will reassemble all but the fastest
 pieces into a rubble pile. Because collisions among
(25)asteroids are relatively frequent, most large bodies
 have already suffered this fate. Conversely, most
 small asteroids should be monolithic, because impact
 fragments easily escape their feeble gravity.


题目:

According to the passage, which of the following is a prediction that is based on the strength of the gravitational attraction of small asteroids?

选项:

答案:

B

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解答:

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解答: 张慧雯

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解答:

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解答: 张慧雯老师

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