题目

下列说法中正确的是A. 电流做功的过程就是电能转化为内能的过程B. 电功率是表示的电流做功快慢的物理量C. 用电器的电功率越大，做功就越多D. 用电器的额定功率越大，消耗的电能就越多 答案：【答案】B【解析】试题（1）用电器在单位时间内消耗的电能叫电功率。单位时间内消耗的电能越多，消耗电能就越快，功率值越大。（2）电流做功的过程就是消耗电能的过程，电流做了多少功就是消耗了多少电能。所以，电功率是表示用电器消耗电能快慢的物理量，也是表示用电器做功快慢的物理量Dorothy Brown was very happy as she sat in the theatre listening to the music．Today her little daughter Lauren was giving her   36  concert．She had been waiting for this   37  for years and years．“Now it is here at last,” she thought．“How beautiful her   38  is.”The song made her   39  to the days when she was Lauren’s   40 ．As a young   41 , Dorothy wanted to be a concert singer．She studied   42  in France, Italy and in the United States．“You can become a fine   43  in the future,” her teachers told her．“But you must be   44  to study hard and work for many years．There will be   45  time for anything but music in your life.”Dorothy was   46  at that time and she was   47  that music was all she wanted or needed to   48  her life．For almost a year Dorothy   49  of nothing else．Then she   50  David, a young engineer travelling Europe．They soon fell in   51 ．David asked her to be his  52 ．Dorothy also wanted to marry David．But she loved   53 , too．She didn’t know what to do．David was against her being a singer．He said, “If you want to be a singer, you must forget about getting married．You can’t   54  do both.” Thus her days were gone and would never return.Now Lauren became a singer instead of her, which was her   55 .小题1:A．sorryB．successfulC．firstD．wonderful小题2:A．danceB．momentC．showD．party小题3:A．voiceB．faceC．dressD．life小题4:A．think ofB．bring backC．go backD．come back小题5:A．ageB．friendC．motherD．teacher小题6:A．musicianB．pop starC．ladyD．girl小题7:A．FrenchB．musicC．pianoD．dance小题8:A．actressB．studentC．singerD．dancer小题9:A．preparedB．learningC．drivenD．waiting小题10:A．someB．anyC．noD．enough小题11:A．eightB．eighteenC．eightyD．eighty-eight小题12:A．luckyB．sureC．afraidD．fond小题13:A．fillB．liveC．leadD．take小题14:A．heardB．knewC．talkedD．thought小题15:A．saw offB．learned fromC．heard of D．met with小题16:A．loveB．feelingC．musicD．touch小题17:A．assistantB．teacherC．wifeD．student小题18:A．himB．engineeringC．herselfD．music小题19:A．certainlyB．possiblyC．onlyD．mainly小题20:A．thoughtB．hopeC．purposeD．will