问题 实验题

如图为“研究一定质量气体在压强不变的条件下,体积变化与温度变化关系”的实验装置示意图。粗细均匀的弯曲玻璃管A臂插入烧瓶,B臂与玻璃管C下部用橡胶管连接,C管开口向上,一定质量的气体被封闭于烧瓶内。开始时,B、C内的水银面等高,外界大气压恒定不变。

(1)若气体温度升高,为使瓶内气体的压强不变,应将C管_______(填“向上”或“向下”)移动,直至_____________。

(2)(单选)实验中多次改变气体温度,用Dt表示气体升高的温度,用Dh表示B管内水银面高度的改变量。根据测量数据作出的图线是( )

答案

(1)向下,B、C两管内水银面等高,(2)A

题目分析:(1)气体温度升高,压强变大,B管水银面下降,为保证气体压强不变,应适当降低A管,所以应将C管向下移动,直至B、C两管水银面等高,即保证了气体压强不变.

(2)实验中多次改变气体温度,用表示气体升高的温度,用表示B管内水银面高度的改变量.压强不变时体积变化与温度变化的关系是成正比的,所以根据测量数据作出的图线是A.

阅读理解

Our village carpenter (木匠) , John, came one day and made a dining table for my wife. He made it just the right size for the space between the two windows. When I got home that evening, John was drinking a cup of tea and writing out his bill for the job.

My wife said to me quietly,“That’s his ninth cup of tea today. ”But she said, in a loud voice,“It’s a beautiful table, dear, isn’t it?”

“I’ll decide about that when I see the bill. ”I said.

John laughed and gave me his bill for the work. I read:

One dining table                        10 November, 1998

Cost of wood                            $17. 00

Paint                                   $1. 50

Work, 8 hours ( $1 an hour )            $8. 00

Total                                   $36. 50

When I was looking at the bill, John said, “It’s been a nice day, hasn’t it?Quite sunny. ”

“Yes. ”I said. “ I’m glad it’s only the tenth of November. ”

“Me, too. ”said John. “You wait — it’ll be a lot colder by the end of the month. ”

“Yes,colder — and more expensive! A dining table will be $20 more expensive on November 30, won’t it, John?”

John looked hard at me for half a minute. Was there a little smile in his two blue eyes?I gave his bill back to him.

“If there isn’t too much trouble, John,” I said,“please add it up again. You can forget the date…”

I paid him $26. 50 and he was happy to get it.

小题1:Why did John talk about the weather when the writer was looking at the bill?

A.Because he didn’t want the writer to go through the bill carefully.

B.Because it was really a fine day.

C.Because he wanted the writer to check the bill carefully.

D.Because he wanted to tell the writer what the weather was like.小题2:The writer thought John would ask for _______ if he made a dining table on the last day of November.

A.$20. 00

B.$46. 50

C.$56. 50

D.$26. 50小题3:When the writer gave John the money, he was happy because _______.

A.he got what he should get for his work

B.he got much more money for his work

C.he got the money easily

D.he didn’t have to add up the costs again小题4:From the story we know that ______.

A.John made a mistake in the bill

B.John tried to fool the writer in order to get more money for his work

C.John had written out the bill before the writer got home

D.John still wanted to get $36.50 for his work in the end小题5:What do you think of the writer? He is ______.

A.honest

B.clever

C.foolish

D.afraid

判断题