问题 选择题
“嫦娥一号”的姐妹星“嫦娥二号”,于2010年10月1日18时59分57秒在西昌卫星发射中心发射升空,并获得了圆满成功.在奔月的天路上飞驰112个小时后,于10月6号上午“嫦娥二号”在近月点100公里处踩下刹车,成功实施第一次近月制动.这标志着“嫦娥二号”由地月转移轨道进入周期约12小时的环月轨道,从追月者到绕月者,变成了月球的卫星,关于“嫦娥二号”的下列说法中正确的是(  )

A.最后一次在近地点加速后的卫星的速度必须等于或大于第二宇宙速度

B.卫星在到达月球附近时需刹车减速是因为卫星到达月球时的速度大于月球卫星的第一宇宙速度

C.卫星在到达月球附近时需刹车减速是因为卫星到达月球时的速度大于月球卫星的第二宇宙速度

D.若绕月卫星要返回地球,则其速度必须加速到大于或等于月球卫星的第三宇宙速度

答案

答案:C

问答题 简答题
问答题

A Frenchman, the psychologist Alfred Binet, published the first standardized test of human intelligence in 1905. (46)But it was an American, Lewis Terman, a psychology professor at Stanford, who thought to divide a_test taker’s "mental age," as revealed by that score, by his or her biological age to derive a number that he called "IQ". It would be hard to think of a pop-scientific coinage that has had a greater impact on the way people think about themselves and others.

(47)No country: embraced the IQ more thoroughly than the U.S., where millions of people have their IQ measured annually, many with a direct descendant of Binet’s original test, although not necessarily for the purpose Bin et intended. He developed his test as a way of identifying public school students who needed extra help in learning, and that is still one of its leading uses.

But the broader and more controversial use of IQ testing has its roots in a theory of intelligence—part science, part sociology—that developed in the late 19th century, before Binet’s work and entirely separate from it. (48)Championed first by Charles Darwin’s cousin Francis Galton, it held that intelligence was the most valuable human attribute, and that if people who had a lot of it could be identified and put in leadership positions, all of society would benefit.

Terman believed IQ tests should be used to conduct a great sorting out of the population, so that young people would be assigned on the basis of their scores to particular levels in the school system, which would lead to corresponding socioeconomic destinations in adult life. The beginning of the IQ-testing movement overlapped with the eugenics movement—hugely popular in America and Europe among the "better sort".

In 1958 a British sociologist named Michael Young coined the word "meritocracy" to denote a society that organizes itself according to IQ-test scores. Terman and many other early advocates of IQ testing had in mind the creation of an American meritocracy, though the word didn’t exist then. (49)They believed IQ tests could be the means to create, for the first time ever, a society in which advantage would go to the people who deserved it rather than to those who had been born into it.

In order to believe this, though, you have to believe that merit and a score on an IQ test are the same thing. (50)Long before IQ was invented, America prided itself on beinga country without a class system, in which people of talent and industry would rise and be rewarded. The advent of intelligence tests did not dramatically affect the degree of social mobility in the U.S.—at least not enough for any change to show up in the social-science data.

(47)No country: embraced the IQ more thoroughly than the U.S., where millions of people have their IQ measured annually, many with a direct descendant of Binet’s original test, although not necessarily for the purpose Bin et intended.