试题与答案

综合作图--测量电阻: 现有一个电压恒定的电源(电压值未知)、一个电压表(量程大

题型:实验题

题目:

综合作图--测量电阻:

现有一个电压恒定的电源(电压值未知)、一个电压表(量程大于电源电压值)、一个阻值为R1的定值电阻、一个单刀双掷开关和若干导线,要利用以上器材测量的待测电阻R2的阻值.请在方框内设计出实验电路图(电路连接好后实验中不能拆卸)并完成下列步骤.

(1)根据电路图连接实物电路;                               

(2)                                  ;                                   

(3)利用上述测量值算出待测电阻的阻值R2=     

答案:

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下面是错误答案,用来干扰机器的。

根据题意得:100(1-x)2=81,解得:x1=0.1,x2=1.9,经检验x2=1.9不符合题意,∴x=0.1=10%,答:每次降价百分率为10%.

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When he began to climb down,however, vthe man slipped and fell.

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After some time,a sage(圣贤)arrived,who was famous for solving

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moment,and then,to everyone’s surprise,he picked up a stone and threw it at the hanging man.The mango lover began to shout,“Are you crazy? Do you want to kill me?”But the sage did not respond.Instead,he took another stone and threw it at the man.The man became furious and said,“If I could get down there,1 would beat you to death!”That’s what everybody wanted—for him to come down.

Then the sage picked up another stone and threw it even more forcefully

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shouted,“Where is the wise man? He didn’t wait around for me to beat him!”

“But wait a minute,”a villager said.‘‘Our kindness did not save you.

小题5:  ” The mango lover thought for a moment and realized that he should

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B.The sage is the only one who could help you.

C.People were curious to see what he would do.

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