问题 选择题

用一只量筒、水、一根细针做实验,来测小木块(能放进量筒中)的某些物理量。下列说法中正确的是

A.能测木块的体积

B.能测木块所受的浮力

C.能测木块的质量

D.能测木块的密度

答案

ABCD

A、在量筒中倒入适量的水,记下体积,将木块按入水面以下,记下总体积,两者之差就是木块体积.此选项正确;

B、浸没的木块受到的浮力等于排开的水重,测出排开的水的体积,用F=GgV可以得到浮力.此选项正确;

C、漂浮物体的质量等于排开的液体的质量.使木块漂浮,测出排开的水的体积,利用m=mV得到木块质量.此选项正确;

D、选项C得到木块的质量,选项A得到木块的体积,利用ρ="m/" V 可以得出木块的密度.此选项正确.故选A、B、C、D.

单项选择题
完形填空

I live in Albuquerque, New Mexico, and some homeless people frequent the stoplights. I often gave money to the homeless, feeling  36 for their bad luck. But later I became a single mom with no home, a huge debt. As a result, I  37 giving and became very  38 .                                   

Things started to 39  for me. Again I had a home, and plenty of food, and I started to   40   myself out of debt. One day we saw a homeless person with the  41  , “Will work for food.” I 42  . My daughter commented, “Mommy, you 43   to give to those people in  44  .’’ I replied, “Honey, they just use that money for alcohol or other 45 things.” She didn’t respond. But when I said that, it didn’t feel right.

Three days later, I was driving to 46 up my daughter from school. A man was standing on the corner, and something deep 47   me said, “Just help him.” 48   I rolled down my window, and he ran over with enthusiasm, saying “God bless you, I only need 77 cents.” I  49 into my ashtray and strangely enough, there sat three quarters and two pennies.

I scooped(抓起)it up and gave it to him. He  50  with joy and tears in his 51  , “Wow, you just made it  52   for me to see my mom for Christmas! Thank you; the bus that had this great sale is  53   in 20 minutes!” It was a moment I’ll never forget. I think that man won’t forget it either, 54   I was the one who got the best  55   in life -- GIVING.

36. A. pleased             B. sorry                C. nervous          D. notable 

37. A. stopped            B. refused           C. considered               D. continued  

38 A. bitter                B. disappointed     C. satisfied          D. happy

39. A. reform                      B. decline           C. end                D. change

40. A. pull                B. drive              C. persuade         D. concern 

41. A. gesture             B. symbol           C. sign                  D. sentence 

42. A. passed by           B. gave in          C. stood up            D. held on  

43. A. expected            B. attempted       C. promised            D. used

44. A. shock                 B. happiness        C. comfort                D. need 

45. A. dim              B. bad                   C. exciting         D. anxious 

46. A. pick                 B. look              C. ring               D. beat  

47. A. beside             B. inside          C. behind          D. above

48. A. So                B. Otherwise      C. However       D. Moreover 

49. A. climbed            B. jumped         C. saw              D. reached

50. A. turned around     B. broke down    C. burst out         D. spoke up

51. A. eyes              B. face           C. nose              D. mouth

52. A. necessary       B. possible             C. important      D. nice

53. A. taking             B. operating       C. leaving              D. driving

54. A. but            B. or                    C. and           D. nor       

55. A. award                 B. message            C. gift            D. lesson