问题 填空题

欧姆定律的内容是:导体中的______与______成正比,与______成反比.公式为______.

答案

欧姆定律的内容为:导体中的电流与导体两端的电压成正比,与导体电阻成反比,计算公式为I=

U
R

答:电流,导体两端的电压,导体的电阻,I=

U
R

阅读理解

阅读短文,判断下列句子是否符合短文内容。符合的写“A”,不符合的写“B”。

Water is the most important in our lives. Not Many people understand this but it’s quite true. The human body can go without food for a long time. We’ve got many examples for this. Yet two or three dayswithout water can usually make people die. Man can’t live without water.

Many people don’t understand how much water the human body needs to work well, and many people, especially young people, do not drink enough water, even in very hot weather. About two thirds of our body is water. When we do sports, some of the water will get away from our body. If we don’t drink some water, our body won’t have enough water. And if we don’t have enough water, we’ll feel tired and many of us will get ill. So you know how important water is to us.

But at present we face water crisis(危机). Water is becoming less and less. So, we should protect water resources(资源) and try our best to save water in our daily life. Here are some tips for saving water:

1. Turn off the tap(水龙头) in lime.

2. Take shorter showers.

3. Don’t let water run while washing your face and reuse the water after we finish washing.

4. Encourage your friends and neighbors to join in the action of saving water.

小题1: Nobody can live without water.

小题2: About one third of our body is water

小题3: If one doesn't have enough water, he’ll feel tired and may get ill.

小题4: We’d better take longer showers and let water run while washing.

小题5: It’s our duty to protect water resources and save water.

选择题