小东在实验室探究电流与电阻的关系。（1）在研究过程中，小东

（1）在研究过程中，小东用到了控制变量法，应保持电路中电阻R的不变；现在电路中的电阻R=10Ω，闭合开关后，电流表和电压表的读数分别为6V、0.6A，记录数据后，把电路中的电阻R换成20Ω，下一步应该操作。

（2）小东测量了每个已知阻值的定值电阻的电流，记录了如下表所示的实验数据。请你对表格中的数据进行分析，归纳出在通过导体的电流与导体电阻阻值之间的关系是：。

答案

（1）两端电压调节滑动变阻器滑片，使电压表示数为6V

（2）当电阻两端电压为6V不变时，通过导体的电流与导体的电阻成反比，比例系数为6AΩ

题目分析：要探究电流和电阻的关系，应保持电阻两端的电压不变；分析表格中数据，得出电流和电阻的关系：电压不变，导体中的电流与电阻成反比．

（1）电流和电压、电阻有关，要探究电流与电阻的关系，应保持电路中电阻R两端的电压不变；

换接不同的电阻后，电阻两端的电压也会发生变化，应通过调节话懂不懂滑片，使电压表的示数保持6V不变；

（2）由表格中数据知，电压保持6V不变，导体的电阻越大，通过的电流越小，且电阻增大为原来的几倍，电流便减小为原来的几分之一，可得电阻两端电压不变，通过导体的电流与导体的电阻成反比．比例系数为6AΩ

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