在研究“导体的电阻跟横截面积关系”的实验中,用图所示的装置把两根电阻AB和CD分

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问题:

在研究“导体的电阻跟横截面积关系”的实验中,用图所示的装置把两根电阻AB和CD分别接入电路,AB比CD的横截面积小.将AB连入电路时,电流表示数为I1;将CD连入电路时,电流表示数为I2,且I2>I1

(1)AB和CD两根电阻丝还要满足的条件是:①______;②______.

(2)分析实验结果,得出的结论是______.

考点:影响电阻大小的因素
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焦炭塔冲塔后,会发生()。

A、顶温上升

B、塔压力上升

C、分馏塔底温度上升

D、分馏塔底液面上升

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健康新地平线的含义是什么?

题型:填空题

The Body Temperature

The temperature of your body should be always just the same, no matter whether the weather is hot or cold. That is why the doctor uses his thermometer (温度计)when your are sick.

The body keeps the same temperature all the time ,because it balances the heat it produces and it gives off. It is always burning up food and , producing heat. It can produce heat faster when it needs to give off heat than when it becomes too warm. Let’s see how this happen.

The heat of your body is given off mainly through the skin. When you are cold, your skin is tight and shows “good flesh”. When you get chilly, you must dance around to keep warm or else you will shiver. Then your muscles begin to work, burn up fuel, and produce more heat. It is not pleasant to shiver, so you usually prefer to warm up by exercise, or put on more clothes to keep heat in.

When you are warm, the skin is loose and soft. It is so supplied with blood that heat is given off rapidly. If you get too warm, you begin to sweat ,and more body heat is used in evaporating the moisture(水蒸气) from your skin. You wear less clothing, too, in warm weather or warm room, so that warm can be given off freely. You feel less like exercising because your body is warm already, and the extra heat produced by exercise makes you uncomfortable.

You can see from the way you feel differently in different kinds of weather. In summer, when it is warm, you feel tired and lazy. You do not care to work or play, but enjoy lying and doing nothing. When you get out of doors in winter, the cold air makes you feel lively. You want to play.

小题1:Which is another title suitable of the passage?

A.The Patients’ Temperature

B.The Body Temperature Should Always Be the Same

C.The Body Temperature

D.The Temperature and Your Skin小题2:How does the body keep the same temperature all the time?

A.It is always producing heat from food.

B.It gives off the heat produced in it.

C.It balances the heat it gets and loses.

D.It stops producing heat when necessary.小题3:When one feels chilly, which of the following will he do?

A.His skin becomes tight in order to keep warm.

B.He does exercises to make his muscle produce more heat.

C.He puts on more clothes to keep heat in.

D.He keeps shivering to produce more heat.小题4:When in summer, people prefer to_____.

A.work

B.play

C.do exercise

D.relax and do nothing

题型:填空题

关于居民营养状况调查和监测的意义,下列叙述错误的是()

A.了解居民营养状况动态变化情况

B.推测营养与疾病间的关系

C.掌握某一时间断面居民营养状况

D.反映社会营养措施的效果

E.获得机体生理需要量资料

题型:填空题

两谷坡相交部分叫谷底,谷底最低点连线称为()

A.等深线

B.山脊线

C.山谷线

D.地性线

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