问题 问答题

小强同学探究水的蒸发与水面上的空气流动的速度的关系,做了如下的实验:取两个大小不同的蝶子,分别倒入少量的水,然后对着其中一个碟子对其吹热风,这个碟子的水很快变干,于是小强同学得出结论,水面上的空气流动越快水蒸发越快的结论,你认为小强的得出的结论对吗?他所用的探究方法有什么不妥之处?

答案

两个碟子不同,代表了液体的表面积不同,又用电吹风给碟子里的水吹热风时,在加快了液面空气流动的同时,也提高了液体的温度.影响液体蒸发快慢的因素三个都发生了变化,因此小强的结论不妥当.

要探究液面上空气流动的速度对液体蒸发快慢的影响,就要控制液体的温度和表面积都不变,只让液体上方的空气流动速度不同;采取的办法可以用电吹风吹冷风,观察水蒸发的快慢即可.

阅读理解

阅读理解。

     Mr. and Mrs.Turner live outside a small town.They have a big farm and they are always busy working on it. Their son, Peter, studied at a middle school. The young man studied hard and did well in his lessons. It made them happy.

     Last month Peter finished middle school and passed the entrance examination (升学考试).Mrs.Turner was very happy and told the farmers about it.

     Yesterday morning the woman went to the town to buy something for her son. On the bus she told one of her friends how clever and able her son was. She spoke very loudly. All the people in the bus began to

listen to her.

     "Which university (大学) will your son study in?" a woman next to her asked.

     "In the most famous university in our country!" Mrs. Turner said happily.

     "The most famous university?""Oxford University (牛津)."

     Most of the passengers (乘客) looked at her carefully. Some of them said to her, "Congratulations!"

A woman said, "I'm sure he'll know Fred Smith.""Who's Fred Smith?""He's my son." "Does he study in

the university, too?" "No, "said the woman. "He is one of the professors."

l. The story happened in _______.

A. America

B. France

C. Germany

D. England

2. Mr. and Mrs. Turner were happy because _______.

A. their son did well in his lessons

B. they have a big farm

C. they have a good harvest

D. their son studied at a middle school

3. Mrs. Turner wanted everyone to know _______.

A. her son finished middle school

B. her son was handsome

C. her son was going to study in a university

D. her son was very friendly to others

4. Mrs. Turner spoke so loudly in the bus that _______.

A. her friend could hear her

B. all the people could hear her

C. she hoped to make all the people happy

D. she hoped they would say congratulations to her

5. Which of the following is true? _______.

A. The woman wasn't interested in Mrs. Turner's words

B. Mrs. Turner knew nothing about the famous university

C. The woman wanted to stop Mrs. Turner from showing off (炫耀)

D. The woman next to Mrs. Turner wanted to show off her son, too

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