一个质量不计的轻弹簧,竖直固定在水平桌面上,一个小球从弹簧的正上方竖直落下,从小

题型:选择题

问题:

一个质量不计的轻弹簧,竖直固定在水平桌面上,一个小球从弹簧的正上方竖直落下,从小球与弹簧接触开始直到弹簧被压缩到最短的过程中,小球的速度和加速度的大小变化情况是(   )

A.加速度越来越小,速度也越来越小

B.加速度先变小后变大,速度一直是越来越小

C.加速度先变小,后又增大,速度先变大,后又变小

D.加速度越来越大,速度越来越小

考点:牛顿第二定律
题型:选择题
完形填空。
       When I was in the third grade, I wanted to be just like Mrs. Abshere. She always had a   1   for her
  students. She made us feel both special and wanted. I _2   felt that Mrs. Abshere cared about me. Her
  patience and kindness helped me   3   many hard times.
       One day, after I got home, the police suddenly came and arrested (逮捕) my parents. I was   4   to
  death! I held on to my brother and sister as we were   5   a children's home.
       As my parents waited for their   6  , my brother, sister and I waited in the children's home. Soon days
  turned into weeks. When I was told that they would be in prison for six months, I   7   on my bed and
  cried for hours. I was mad at the world and no longer saw any future for myself. Just at this very moment
  one of the girls came running up to me. "Hey, there's a lady here to see you. I think it's your mom." _8_ it
   be true?
       When I got to the end of the hallway, there stood Mrs. Abshere! She held her arms out to me.
  "Honey, I know   9   is better than your mom, but I love you, too!" I hugged her and  10   thanked God
  for bringing this angel thirty miles out of her way to see me.
       As I  11  Mrs. Abshere around the grounds, I began to feel  12   again. I was so excited to show her
   off to all my new friends.
       Two weeks later, I said good-bye to all my friends and moved across the state to live in another city
  with my grandparents.
       Sixteen years later, I  13  Mrs. Abshere, so that I could tell her how grateful (感激的) I was. When I
   found her, we had the most wonderful conversation. I felt so much  14  telling her that I was only a year
  away from becoming a teacher myself. "Oh! That's great. You can teach students in my room!"  15 ,
  perhaps I will be returning to Mrs. Abshere's classroom soon, only this time as a peer (同行) and a very
  grateful friend.
( )  1  A. message    
( )  2  A. surely      
( )  3  A. with        
( )  4  A. lonely      
( )  5  A. invited    
( )  6  A. news       
( )  7  A. jumped      
( )  8  A. must        
( )  9. A. nobody      
( ) 10. A. carefully  
( ) 11. A. walked      
( ) 12. A. wonderful  
( ) 13. A. searched for
( ) 14. A. patience    
( ) 15. A. so          
B. game    
B. truly  
B. through
B. bored  
B. pushe d
B. reply  
B. fell    
B. can    
B. somebody
B. seriously
B. helped  
B. hopeful
B. rang up
B. shame  
B. because  
C. smile    
C. mainly  
C. out      
C. frightened
C. found    
C. letters  
C. spread  
C. could    
C. anybody    
C. nervously
C. talked  
C. interested
C. called on
C. pride    
C. however  
D. prize      
D. hardly    
D. off        
D. sorry      
D. driven    
D. sentence  
D. slept      
D. may        
D. everybody  
D. silently  
D. saw        
D. relaxed    
D. bumped into
D. hope      
D. though    
题型:选择题

少尿是指24小时尿量少于

A.50ml

B.100ml

C.200ml

D.400ml

E.1000ml

题型:选择题

我省静宁县“香怡”牌苹果醋饮品,被誉为“新一代黄金饮品”,因其解酒护肝、减肥美容、提升免疫力等功效成为人们的新宠.苹果醋(化学式为C4H6O5)是这种饮品的有效成分.

(1)苹果醋中碳、氢、氧三种元素的质量比是(最简整数比)______;

(2)苹果醋中氢元素的质量分数是(精确到0.1%)______.

题型:选择题

原子弹在广岛、长崎爆炸 ,爱因斯坦认为自己一生中最大的错误和遗憾是建议罗斯福研制核武器,并不无遗憾地说:“早知如此,我宁可当个修表匠。”这说明爱因斯坦

A.认为自己应该另选其他职业

B.坚决反对核战争

C.真正知道了核爆炸的危害

D.主张以和平方式解决国际冲突

题型:选择题

掌握"适度"原则的哲学依据是:

A.质和量的统一

B.肯定和否定的相互渗透

C.矛盾同一性和斗争性的相互联结

D.内容和形式的相互转化

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