问题 不定项选择

如图所示,竖立在水平地面上的轻弹簧,下端与地面固定,将一个金属球放置在弹簧顶端(球与弹簧不粘连),并用力向下压球,使弹簧作弹性压缩,稳定后用细线把弹簧拴牢,烧断细线,球将被弹起,脱离弹簧后能继续向上运动,那么该球从细线被烧断到刚脱离弹簧的这一运动过程中

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A.球所受的合力先增大后减小

B.球的动能减小而它的机械能增加

C.球刚脱离弹簧时的动能最大

D.球刚脱离弹簧时弹簧的弹性势能最小

答案

答案:D

单项选择题 A1型题
阅读理解

At exactly eleven Sir Percival knocked and entered, with anxiety and worry in every line of his face. This meeting would decide his future life,and he obviously knew it.

"You may wonder, Sir Percival,”said Laura calmly, “if I am going to ask to be released (免除)from my promise to many you. I am not going to ask this. I respect my father's wishes too much.”

His face relaxed a little, but one of his feet kept beating the carpet.

"No, if we are going to withdraw. (退出)from our planned marriage, it will be because of your wish, not mine.

“Mine?” he said in great surprise. “What reason could I have for withdrawing?

"A reason that is very hard to tell you," she answered. "There is a change in me.”

His face went so pale that even his lips lost their color. He turned his head to one side.

"What change?" he asked, trying to appear calm.

“When the promise was made two years ago,” she said, 44 my love did not belong to anyone. Will you forgive me, Sir Percival, if I tell you that it now belongs to another person?”

“I wish you to understand, “Laura continued, “that I will never see this person again, and that if you leave me, you only allow mc to remain a single woman for the rest of my life. All I ask is that you forgive mc and keep my secret."

‘I will do both those things, “he said. Then he looked at Laura, as if he was waiting to hear more.

"I think I have said enough to give you reason to withdraw from our marriage, “she added quietly.

“No. You have said enough to make it the dearest wish of my life to marry you, ” he said.

小题1:How did Percival feel during his meeting with Laura?

A.Angry.

B.Calm.

C.Nervous.

D.Excited.小题2:We can learn from the passage that        .

A.Laura had once promised to marry Percival

B.Laura's father wished to end her marriage

C.Percival had been married to Laura for two years

D.Percival asked to be released from the marriage小题3:The passage is probably taken out of              .

A.a novel

B.a report

C.a diary

D.an essay