问题 实验题

小明通过实验研究小灯泡灯丝电阻随其两端电压的变化情况.实验时使用的是额定电压为2.5V的小灯泡,通过实验测出了若干组灯丝两端的电压和通过灯丝的电流,并根据实验数据画出了如图所示的图象.由图象可知,灯丝两端电压为2V时,通过灯丝的电流为 _________ A,此时灯丝的电阻为_________Ω;在实验过程中,随着小灯泡两端电压的变大,小灯泡灯丝的电阻值 _________ (选填“保持不变”、“变小”或“变大”).

答案

0.2,10,变大.

阅读理解

阅读理解。

    A little old man and his wife walked slowly into McDonald's one cold winter evening. They took a table

near the back wall, and then the little old man walked to the cash register (收银处) to order. After a while

he got the food back and they began to open it.

   There was one hamburger, some French fries and one drink. The little old man carefully cut the hamburger

in half and divided the French fries in two piles (堆). Then he neatly put the half of the food in front of his

wife. He took a sip of the drink and his wife took a sip. "How poor the old people are!" The people around

them thought. As the man began to eat his hamburger and his French fries, his wife sat there watching him

and took turns to drink. A young man came over and offered to buy another meal for them. But they refused

(拒绝) politely and said that they got used to sharing everything.

   Then a young lady asked a question of the little old lady. "Madam, why aren't you eating? You said that you

share everything. Then what are you waiting for?" She answered, "The teeth."

1. What did the old man order? [ ]

A. One hamburger and one drink.

B. Some French fries and two cups of coffee.

C. One hamburger, some French fries and one drink.

D. One hamburger, some cups of coffee.

2. What did they do after they opened the food? [ ]

A. They left McDonald's.

B. They shared the food.

C. They began to look for seats.

D. They ate the hamburger.

3. What's the meaning of the phrase "took a sip"? [ ]

A. Drank something slowly.

B. Had a rest.

C. Had some snacks.

D. Did nothing.

4. As the old man began to eat things, his wife sat there ______. [ ]

A. talking with him

B. looking at him quite angrily

C. watching him and took turns to drink

D. arguing (争论) with him

5. What can we know from the whole passage? [ ]

A. The old lady wasn't hungry at all.

B. The two old people shared the same teeth.

C. The old lady had a toothache.

D. The old lady didn't feel well.

单项选择题 B1型题