问题 多选题

我国将于今年下半年发射目标飞行器“天宫一号”,若“天宫一号”能在离地面约300km高的圆轨道上正常运行,两月后再发射“神舟八号”飞船并与其进行对接试验.下列说法中正确的是(  )

A.“天宫一号”的发射速度应大于第二宇宙速度

B.对接前,“神舟八号”欲追上“天宫一号”,必须在同一轨道上点火加速

C.对接时,“神舟八号”与“天宫一号”的加速度相等

D.对接后,“天宫一号”的速度小于第一宇宙速度

答案

A“天宫一号”的发射速度不应小于第二宇宙速度,若大于则会脱离地球的吸引.故A错误

     B 若在同一轨道加速,则会做离心运动,不会相遇.故B错误

     C 对接时,半径相同,则加速度相等.故C正确

     D 所有卫星的运行速度都小于第一宇宙速度.故D正确

故选:C    D

阅读理解

I attended a birthday party in 1991. My teacher was then 59 years old. But her fellow teacher said that we were celebrating her 39th birthday! We were all surprised and puzzled.

After the party I was told by the fellow teacher that American women have a special saying about birthdays. If a woman is over 40, or even if she is 80, her birthday is always the 39th. If she is in her thirties, her birthday will be the 29th. And in her twenties, it’s the 19th. They usually have their “real” birthday when they are below 20.

This shows that American women, especially elderly women, are very sensitive(敏感的) about their ages. But my teacher always says, “We want to be younger,” so about the age of Western women, my advice is that if you don’t know it, don’t ask about it; if you really know it, don’t mention it.

小题1:The writer felt the birthday party he attended was ___________.

A.very interesting

B.very strange

C.very common

D.very sensitive小题2:The writer must be from______________.

A.Western countries

B.Eastern countries

C.China

D.the United States小题3:In order to please an old Western woman , you can say to her,“____________”

A.You are so old that you shouldn’t do that.

B.How old are you?

C.You look so young and beautiful.

D.Can I help you, granny?小题4:The writer wants to tell us__________________.

A.that a Western woman always celebrates her 39th birthday

B.not to ask a Western woman’s age whether you know her well or not

C.to ask a Western woman’s age freely

D.not to attend an old Western woman’s birthday party

问答题