雅思听力
雅思阅读
2018-05-17 13:30
来源:
作者:
Answer keys and explanations:
1. E
See the sentences in paragraph 1(There's a dimmer switch inside the sun that causes its brightness to rise and fall on
timescales of around 100,000 years - exactly the same period as between ice ages on Earth. So says a physicist who has
created a computer model of our star's core.) and para.2 (Robert Ehrlich of George Mason University in Fairfax, Virginia,
modelled the effect of temperature fluctuations in the sun's interior.)
2. A B
See para.3: ?i style='mso-bidi-font-style: normal'>Grandpierre and a collaborator, Gábor ágoston, calculated that
magnetic fields in the sun's core could produce small instabilities in the solar plasma.
3. C
See para.8: Edwards believes the small changes in solar heating produced by Milankovitch cycles are then amplified by
feedback mechanisms on Earth.
4. D
See para.11: Nigel Weiss, a solar physicist at the University of Cambridge, is far from convinced. He describes Ehrlich's
claims as "utterly implausible".
5. False
See para.5: for the past million years, ice ages have occurred roughly every 100,000 years. Before that, they occurred
roughly every 41,000 years.
6. False
See para.7: "In Milankovitch, there is certainly no good idea why the frequency should change from one to another,"
... Nor is the transition problem the only one the Milankovitch theory faces.
7. Not Given
See para.8: if sea ice begins to form because of a slight cooling, carbon dioxide?is locked into the ice. That weakens
the greenhouse effect. (The passage doesn抰 mention anything about locking Co2 into ice artificially.)
8. True
See para.9: there is no lack of such mechanisms. "If you add their effects together, there is more than enough
feedback to make Milankovitch work,"?"The problem now is identifying which mechanisms are at work." This is why
scientists like Edwards are not yet ready to give up on the current theory.
9. True
See the sentences in para.9 (According to Edwards, 卙e says. "I can't see any way of testing [Ehrlich's] idea to see
where we are in the temperature oscillation.") and para.10 (Ehrlich concedes this. "If there is a way to test this theory on
the sun, I can't think of one that is practical).
10. constant
See para.2: According to the standard view, the temperature of the sun's core is held constant by the opposing
pressures of gravity and nuclear fusion.
11. orbit
See para.6: Most scientists believe that the ice ages are the result of subtle changes in Earth's orbit, 匛arth's orbit
gradually changes shape from a circle to a slight ellipse and back again roughly every 100,000 years.
12. instabilities
See para.3: ?i style='mso-bidi-font-style:normal'>magnetic fields in the sun's core could produce small instabilities in
the solar plasma. These instabilities would induce localised oscillations in temperature.
13. cycles
See para.4: …allow the sun's core temperature to oscillate around its average temperature of 13.6 million kelvin in
cycles lasting either 100,000 or 41,000 years.
14. random
See para.4: Ehrlich says that random interactions within the sun's magnetic field could flip the fluctuations from one
cycle length to the other.
新东方留学院校库,留学选校有门道
A BETTER YOU,A BIGGER WORLD!
版权及免责声明
①凡本网注明"稿件来源:新东方"的所有文字、图片和音视频稿件,版权均属新东方教育科技集团(含本网和新东方网) 所有,任何媒体、网站或个人未经本网协议授权不得转载、链接、转贴或以其他任何方式复制、发表。已经本网协议授权的媒体、网站,在下载使用时必须注明"稿件来源:新东方",违者本网将依法追究法律责任。
② 本网未注明"稿件来源:新东方"的文/图等稿件均为转载稿,本网转载仅基于传递更多信息之目的,并不意味着赞同转载稿的观点或证实其内容的真实性。如其他媒体、网站或个人从本网下载使用,必须保留本网注明的"稿件来源",并自负版权等法律责任。如擅自篡改为"稿件来源:新东方",本网将依法追究法律责任。
③ 如本网转载稿涉及版权等问题,请作者见稿后在两周内速来电与新东方网联系,电话:010-60908555。
雅思听力
雅思阅读