问题 填空题

(A类题)已知引力常量为G,地球的质量为M,地球自转的角速度为ω0,月球绕地球转动的角速度为ω,假设地球上有一棵苹果树长到了接近月球那么高,则此树顶上一只苹果的线速度大小为______,此速度______(选填“大于”、“等于”或“小于”)月球绕地球运转的线速度.

答案

万有引力提供向心力G

Mm
r2
=mrω2,r=
3
GM
ω2
.根据v=rω0,所以v=ω0
3
GM
ω2

 地球自转的角速度等于同步卫星的角速度,轨道半径越大,角速度越小,知同步卫星的角速度大于月球绕地球转动的角速度,根据v=rω,苹果的线速度大于月球绕地球运转的线速度.

故本题答案为:ω0

3
GM
ω2
,大于

完形填空

Lillian Hanson, a college student, expects to graduate in about two years. What makes Mrs. Hanson different from her classmates is her    46   --73 years old.  She has been studying at college, a few courses at a time, for 27 years.

When Lillian Hanson graduated from high school, she went to the   47   to borrow money for further education. The banker gave her   48   encouragement. He didn't think that a country girl should borrow money to go to college. He thought she should be    49   doing housework or should work on the farm.     50   Lillian Hanson went home and raised a family of nine children instead of going to college.

Mrs. Hanson    51   forgot the dream of getting higher education. When the children

grown up, she   52   again and succeeded. In the class on her first day, when she introduced herself and   53   why she was there and what her aims were, all the other students   54  give her a warm welcome.

Mrs. Hanson finds that the   55   part of going back to school at her age is sitting in class long periods of time. However, she often says she will stick to her dream no matter how difficult it is.

小题1:A. age                           B. interest                      C. accent

小题2:A. club                          B. school                      C. bank

小题3:A. much                                B. no                         C. a little

小题4:A. at college                B. at home                     C. in the office

小题5:A. After                           B. But                         C. So

小题6:A. never                         B. already                      C. often

小题7:A. stopped                         B. tried                        C. refused

小题8:A. regretted                       B. guessed                     C. explained

小题9:A. stood up                       B. ran away                    C. broke out

小题10:A. best                        B. hardest                     C. easiest

单项选择题 共用题干题