问题 选择题

图为伽利略制造的第一个温度计,它可以测量气体的温度.若外部大气压不变,在气温发生变化时,球形容器内气体的体积随之发生变化,使玻璃管内液面上升或下降,从而测量出气温的高低.以下说法正确的是(  )

A.当气温升高,球内气体体积膨胀,玻璃管内液面下降

B.当气温升高,球内气体体积缩小,玻璃管内液面上升

C.当气温降低,球内气体体积缩小,玻璃管内液面下降

D.当气温降低,球内气体体积膨胀,玻璃管内液面上升

答案

当外界气温上升的时候,球形容器内的气体受热膨胀,由于密闭,所以压强增大,使管内的液面下降;

反之,当外界气温下降的时候,球形容器内的气体收缩,由于密闭,所以压强减小,管内的液面上升.故B、C、D错误.

故选A.

完形填空

阅读短文,从A—G七个句子中选择正确选项还原到文中,使短文内容完整,将答案定在答题纸的相应位置上.

Many teenagers have hobbies. But sometimes these hobbies can get in the way of schoolwork, and parents might worry about their child's success at school. Teenagers often think they should be allowed to practice their hobbies as much as they want, Do you agree?

Liu Yu, a fifteen-year-old boy from Shandong, is a running star. He is on his school running team and has always wanted to be a professional athlete. 小题1:___"Of course we want to see Liu Yu achieve his dreams," says Mr Liu, "and we know how much he loves running. That's great, and my wife and I have watched him in every one of his races. 小题2:___ But we do think that our son needs to be realistic. Now that he is getting older, he needs to think about what will happen 小题3:____ Liu Yu doesn't really agree. "Well, I think I should be allowed to make decisions for  myself," he says. "My parents have always taught me the importance of working hard and not just to do what I enjoy. I understand this. 小题4:___ Being a professional runners is the only thing I have ever wanted to do.

Mr and Mrs Liu believe that Liu Yu should study hard in the evenings, and so they don't allow him to practice running on school nights."I know this seem strict," says Mrs Liu,"but we think we're doing the right thing. He has to understand that very few people can become professional athletes. It's very difficult dream to achieve.  We don't allow him to practice every day 小题5:_____

A.if he doesn't become a professional runner in the end.

B.So, we don't agree that he is always running.

C.However, his parents won't allow him to train as much as he would like to.

D.No one could stop me running.

E.A.But I 'm serious about running.

F.because we think he needs to spend time on his homework.

G.We have nothing against running.

问答题 简答题