![](https://img.xkw.com/dksih/QBM/editorImg/2024/3/2/b14d2410-df46-4b8e-b4d9-55a424bcb506.png?resizew=426)
(1)圆柱体的直径为
(2)已知实验中所用的滑动变阻器阻值范围为0~10Ω,电流表内阻约几欧,电压表内阻约20kΩ。电源为干电池(不宜在长时间、大功率状况下使用),电动势E=4.5V,内阻很小。则以下电路图中
A.
![](https://img.xkw.com/dksih/QBM/editorImg/2024/3/2/e50cb0ad-3e6a-4c21-bd8f-e4640c5989f0.png?resizew=156)
![](https://img.xkw.com/dksih/QBM/editorImg/2024/3/2/92fd3913-68f2-42c2-8d6b-a1431acd0ab1.png?resizew=155)
C.
![](https://img.xkw.com/dksih/QBM/editorImg/2024/3/2/82e22b56-edb5-4c90-b78c-7f07bfc46781.png?resizew=144)
![](https://img.xkw.com/dksih/QBM/editorImg/2024/3/2/f5fe42a1-1553-4c77-963e-3fc2c0d5c2c3.png?resizew=137)
(3)若流经金属丝的电流为I,圆柱体两端之间的电压为U,圆柱体的直径和长度分别为D、L,测得D、L、I、U表示的电阻率的关系式为ρ=
2 . 实验小组测量某弹性导电绳的电阻率。实验过程如下:
装置安装和电路连接。如图(a)所示,导电绳的一端固定,另一端作为拉伸端,两端分别用带有金属夹A、B的导线接入如图(b)所示的电路中。先闭合开关S1、S2,调节R,使电压表和电流表的指针偏转到合适的位置,记录两表的示数U0和I0。
(1)然后断开开关S2,电流表的示数
(2)多次拉伸导电绳,每次都测量并记录AB间的距离L和导电绳横截面积S,调节滑动变阻器R的滑片的位置,使电流表的示数为I0,记下此时的电压表示数U。绘制如图(c)所示的图像。已知图线的斜率为k、与纵轴的截距为d,则弹性导电绳的电阻率ρ==
(3)若考虑电流表的内阻,则(2)中的电阻率的测量值
(1)该实验小组用刻度尺测量其长度L、螺旋测微器测量其直径D,某次直径测量结果如图所示:D=
![](https://img.xkw.com/dksih/QBM/editorImg/2023/3/26/e2d7817a-e560-4196-899d-a43fdeea698e.png?resizew=194)
(2)实验使用的滑动变阻器的阻值为0~20Ω,请将如图实际测量电路补充完整
![](https://img.xkw.com/dksih/QBM/editorImg/2023/3/26/e094ef6f-e97c-4754-b122-3308f4d1a3e1.png?resizew=259)
(3)闭合开关前,滑动变阻器的滑片应置于
(4)某次实验时,电压表的示数为U,电流表的示数为I,用实验测量的物理量L、D、U、I表示电阻率,则表达式为ρ=
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ce2581ae160692cd7e2686226fe5e2c6.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/15/5c567772-794e-4205-bba0-78962ea3ab9b.png?resizew=205)
(1)用游标卡尺测量有效长度时,测得的结果如图所示,则长度
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fd1846e964fd60c54888a3c706a97442.png)
(2)她先用多用电表的欧姆挡粗测,发现用“
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2468403b3eba9e40bfa36f464e927738.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2468403b3eba9e40bfa36f464e927738.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/15/4df9432f-3950-4047-9bc7-5082538de8b1.png?resizew=339)
(3)用改换倍率后的欧姆挡测得待测电阻大致阻值如图,现备有下列器材进行进一步测量:后用伏安法更精确地测量其电阻Rx,要求测量数据尽量精确且电压从零开始增加,可供该同学选用的器材除开关、导线、待测电阻Rx外还有:
A.直流电源(24V)
B.电压表(量程0~15V,内阻约10kΩ)
C.电压表(量程0~50V,内阻约50kΩ)
D.电流表(量程0~10mA,内阻约为100Ω)
E.电流表(量程0~25mA,内阻约为30Ω)
F.滑动变阻器(最大阻值50Ω)
G.开关和导线若干
为了保证实验顺利进行,并使测量误差尽量小,电压表应选
(4)本实验的测量电路适合用电流表的
(5)由于电表内阻的影响,Rx的测量值较真实值
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/21/eb957ce1-bb8a-4ffd-908c-4d2e6637ebef.png?resizew=397)
(1)用刻度尺量得铅笔芯长度L=20.00cm,用螺旋测微器测量铅笔芯的直径如图乙所示,则铅笔芯的直径d=
(2)该小组用多用电表测得铅笔芯电阻约为6Ω,实验室还提供了下列器材:
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/21/7ae52c81-dd5f-44df-849c-ce33c0f29d8c.png?resizew=129)
A.电流表(0~3A,内阻约0.5Ω)
B.电流表(0~0.6A,内阻约1Ω)
C.电压表(0~15V,内阻约30kΩ)
D.电压表(0~3V,内阻约6kΩ)
E.滑动变阻器(0~5Ω)
F.电源(电动势为3V,内阻不计)
G.开关、导线若干
为了进一步精确测量铅笔芯的电阻率,且实验要求电压表示数可从零开始调节,电流表应选
(3)请将虚线框中实验电路图补充完整;
(4)实验测量过程中,电压表示数为U,电流表示数为I,则铅笔芯电阻率的计算式为ρ=
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/171102a883b22fe6ca578efc8926f5b8.png)
(1)该实验小组分别用20分度的游标卡尺、螺旋测微器测量其长度
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0c88d9142df6ba8e43c1a93bd04a1362.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fd1846e964fd60c54888a3c706a97442.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9a6d85799453899836bc34ad276ec80e.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/10/5/6ad4486c-cb6f-4b5c-b36d-16c2b90b0405.png?resizew=356)
(2)该实验小组用如图丙所示实验电路测量其电阻值。闭合开关前,滑动变阻器的滑片应置于
![](https://img.xkw.com/dksih/QBM/editorImg/2023/10/5/aa6bc23b-68a3-4dba-a44e-e7d7eadd834a.png?resizew=148)
(3)某次实验时,电压表的示数为U,电流表的示数为I,若用
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b763290c8cb341f8c5b268ccc22e61bc.png)
(1)用游标卡尺测量其长度如图1,由图可知其长度L=
![](https://img.xkw.com/dksih/QBM/editorImg/2022/9/1/fe91dc7f-98d1-4263-9206-1e65f4641b02.png?resizew=449)
(2)该同学想用伏安法精确地测量其电阻R,现有的器材及其代号和规格如下:
待测圆柱体电阻R(电阻约220Ω);
电流表A1(量程0~5mA,内阻约50Ω);
电流表A2(量程0~15mA,内阻约30Ω);
电压表V1(量程0~3V,内阻约10kΩ);
电压表V2(量程0~15V,内阻约25k
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0047f659c182291c84c224df6b5e993f.png)
直流电源E(电动势4V,内阻不计);
滑动变阻器R(阻值范围0~15Ω,允许通过的最大电流2.0A);
开关S;导线若干。
为使实验误差较小,要求测得多组数据进行分析,电流表选用
(3)请在下面框中画出测量的电路图
![](https://img.xkw.com/dksih/QBM/editorImg/2022/9/1/62e0d877-181b-4043-935e-c199a87e45fb.png?resizew=427)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/7/30/5baa7d63-6840-4b3d-ab5e-960685f611d9.png?resizew=399)
(1)补充完成实物图的连线
(2)用螺旋测微器测得导线直径如图甲所示,其读数为
(3)将P移到金属丝
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/84abbfb85a00f48b5db11eeb76b8d134.png)
(4)适当向a端滑动P,闭合开关S,调节电阻箱使电流表示数为
(5)重复步骤(3),直到记录3组L和R值为
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/172722d11ea7e01411fa06dbb82f46ee.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9fbd49bf20f987c05b4d36e31549075c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/87f93f4e10d9672fa6bd67243bc23d4a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9efc18a5bb2e53586331b2a58538a48b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/19f20f21a9d50b61dac519a3ddab539d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5a2c4640b2bee411935f588fc5433c74.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9942091e83e1d59af01f499a0caee212.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cf3834d7ec7531f3c3c0ce9b286f7a49.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6b26d0e154ef213ebe194b8b5e519f13.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c4764374bd2fb78e59cd0b283637baeb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/736a256c1edd1aa8627b3c252f28a022.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c63055a5d6916f99d07fede49120753f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/736a256c1edd1aa8627b3c252f28a022.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9efc18a5bb2e53586331b2a58538a48b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8ca6398de479e3b803ca49c5900333d3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/19f20f21a9d50b61dac519a3ddab539d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3ea8317978ca6eebda7048c90e71fec2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4aa0df7f1e45f9de29e802c7f19a4f64.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b7cdda73986c64dba757a3c420e0586d.png)
实验步骤如下:
A.用10分度游标卡尺测量玻璃管的内径
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5c02bc0c74292b1e8f395f90935d3174.png)
B.向玻璃管内注满纯净水,并用刻度尺测量水柱长度
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0c88d9142df6ba8e43c1a93bd04a1362.png)
C.把S拨到1位置,记录电压表
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c4764374bd2fb78e59cd0b283637baeb.png)
D.把S拨到2位置,调整电阻箱阻值,使电压表
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c63055a5d6916f99d07fede49120753f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c4764374bd2fb78e59cd0b283637baeb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4aa0df7f1e45f9de29e802c7f19a4f64.png)
E.改变玻璃管内水柱长度,重复实验步骤C、D,记录每一次水柱长度
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0c88d9142df6ba8e43c1a93bd04a1362.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4aa0df7f1e45f9de29e802c7f19a4f64.png)
F.断开S,整理好器材。
![](https://img.xkw.com/dksih/QBM/editorImg/2022/7/16/5cb9c63f-c80f-457f-8106-bd99db757af1.png?resizew=630)
(1)测玻璃管内径
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5c02bc0c74292b1e8f395f90935d3174.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7c98c59cd4749afdd21e73529fc84323.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/21f3bf70722b22983c120d008d097602.png)
(2)玻璃管内水柱的电阻
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ce2581ae160692cd7e2686226fe5e2c6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/67c1313842b62428737610b14806d883.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9efc18a5bb2e53586331b2a58538a48b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/19f20f21a9d50b61dac519a3ddab539d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4aa0df7f1e45f9de29e802c7f19a4f64.png)
(3)利用记录的多组水柱长度
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0c88d9142df6ba8e43c1a93bd04a1362.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4aa0df7f1e45f9de29e802c7f19a4f64.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c44f4a09777a224f8fa909e7e2c3338b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b30db97c39edcede2f0e7d4e075fecec.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9942091e83e1d59af01f499a0caee212.png)
(4)电导率是电阻率的倒数,是检验纯净水是否合格的一项重要指标,那么不合格的纯净水的电导率相对
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/627d1038ec568d0540e3258528b2533f.png)
操作如下:
(1)测量热敏电阻在
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/627d1038ec568d0540e3258528b2533f.png)
A.电源E(电动势为
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0ae62ccc477cd41615b417464841047f.png)
B.电流表A(量程为
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5c5c631f2750511e61b1fbcca001dd5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a24b21ca0718323a3bb9818a3f92875c.png)
C.电压表V(量程为
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0ae62ccc477cd41615b417464841047f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c2d5329b0fe942daf249a6d207b5d8ea.png)
D.滑动变阻器
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9efc18a5bb2e53586331b2a58538a48b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5d757a8853133814c9a9753443c1cf82.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/000fc5a7140553c3fc4b3e446287962e.png)
E.滑动变阻器
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/19f20f21a9d50b61dac519a3ddab539d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/859576753fd99be483c2574d2e521a9c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c6df49dc3857b53963eab2d7f5f8279a.png)
F.热敏电阻
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/088fe9f953944af0c5512dd2deb5d1bd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2b5b18cd21d4707d48838853590ded22.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/7/8/7cb88f62-c79a-40c8-a3c8-1784a81c30dc.png?resizew=756)
①为了更准确测定阻值,滑动变阻器应选择
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9efc18a5bb2e53586331b2a58538a48b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/19f20f21a9d50b61dac519a3ddab539d.png)
②对热敏电阻加热至60℃,保持温度不变,调节滑动变阻器,得到电压表和电流表的多组数据,已在图8丙中描好点,请在图中
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dd1fd3cc33190245791eddc26c629b9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/40542af817ca6d3721cac25bba07f91f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cffa35373ec4e4684107b42adb7a5161.png)
(2)调试报警器
①按照图丁连接器材,报警器报警最低电流为
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d806f3c728bdd69b0ac1bcb1e211692d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4d64b26bd3eaeebadf07fef49e260282.png)
②在常温下,闭合开关
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d43eb0b274e00cbbc4a210da4165042.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/779629f16056a50f4c06e3996d8e1c82.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4e474bdf61fb3f97f6219aa10aca2e12.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/530f5b63e797195906285c0c03eb9276.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5a2c4640b2bee411935f588fc5433c74.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/98e2599548b7b123f3c8d0b91aacd5de.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/21e68c031d480eb06470a68a3554a3e0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/486f30b44d1e6ffde2b0682808ca010b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6505d03797e57e7f1c8afcefec368175.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c117c482b73f77e39cfffe4292cb648d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5a2c4640b2bee411935f588fc5433c74.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/98e2599548b7b123f3c8d0b91aacd5de.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/21e68c031d480eb06470a68a3554a3e0.png)