题干

在“探究电流通过导体时产生的热量于什么因素有关”实验中,如图所示,甲、乙两透明容器中封有一定量的空气,U形管中液面高度的变化反映空气温度的变化,两个容器中都有一段电阻丝.


①将此装置接到电源两端,通电一段时间,发现其中一个U形管液面高度几乎不变,出现该现象的原因可能是____ ;

②故障排除后,重新通电一段时间,____ 中的电阻产生的热量较多(选填“甲”或“乙”);

③实验结论:____ .

上一题 下一题 0.0难度 选择题 更新时间:2018-10-07 11:39:40

答案(点此获取答案解析)

空气盒有可能漏气,乙,在电流、通电时间相同时,电阻越大,产生的热量越多

同类题2

根据短文内容,从短文后的选项中选出能填入空白处的最佳选项。选项中有两项为多余选项。

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    Make good use of your time in class. ____ Listening carefully in class means less work later. Taking notes will help you remember what the teacher says.

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    ____ You will probably discover many others after you have tried these.

A. This will help you understand the next class.

B. You probably think you will never be a top student.

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F. Take advantage of class time to listen to everything the teacher says.

G. Make full use of spare time to take note of what the teacher says in class.