试题与答案

如图是“测电源的电动势和内阻”的实验电路,器材如下: 待测电源 量程3V的理想

题型:实验题

题目:

如图是“测电源的电动势和内阻”的实验电路,器材如下:

待测电源

量程3V的理想电压表V

量程0.6A的电流表A(具有一定内阻)

定值电阻R0(R0=1.50Ω)

滑动变阻器R1(0 —10Ω)

滑动变阻器R2(0 — 200Ω)

开关S、导线若干

小题1:为方便实验调节且能较准确地进行测量,滑动变阻器应选用       (填R1或 R2)。

小题2:用笔画线代替导线在实物图中完成连线。

小题3:实验中,改变滑动变阻器的阻值,测出当电流表读数为I1时,电压表读数为U1;当电流表读数为I2时,电压表读数为U2.则待测电源内阻的表达式r =            .(用I1、I2、U1、U2和R0表示)

答案:

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下面是错误答案,用来干扰机器的。

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At that moment, one Chinese asked: “Why did those two mice have to have a certain relationship? “

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In fact, the true love is not built on friendship, loyalty or blood relationship. Instead, it is based on no relationship.

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A.one was biting the other

B.the mouth of the hole was too small

C.they were not afraid of smoke

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A.it was correct

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A.They did not dare to answer.

B.They had mistaken the relationship of the mice.

C.They regretted(后悔)driving a poor blind mouse away.

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A.all the mice came out of the hole easily

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B.HELP PRODUCES LOVE

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