![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f85fca60a11e1af2bf50138d0e3fe62.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/3/29/4704553a-ab04-4249-b798-cba9d97cb9e9.png?resizew=234)
(1)用图甲中的螺旋测微器测量电阻丝的直径d。先将电阻丝轻轻地夹在测砧与测微螺杆之间,当测微螺杆快接近电阻丝时,再旋转
(2)用图乙所示电路图测量电阻丝的电阻
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ce2581ae160692cd7e2686226fe5e2c6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/be9b4a83b9aebebf29de0c4406ebf894.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/3/29/b4a7bd25-9c68-45c1-84b4-6312616ec9c8.png?resizew=535)
(3)第一次按图乙所示的电路测量,调节滑动变阻器的滑片,测得多组电压U及电流I的值;第二次将电压表改接在a、b两点测量,测得多组电压U及电流I的值,并作出如图丁所示的U-I图像。则第一次测量得到的图线是
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ce2581ae160692cd7e2686226fe5e2c6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/171102a883b22fe6ca578efc8926f5b8.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/3/29/19d5c69e-f6c4-420f-b70a-96b621a23c9b.png?resizew=278)
2 . 某科技小组为测量一种新型导电材料的电阻率,取一块厚度均匀、上下表面为正方形的该型导电材料,如图1所示。
(1)科技小组用多用电表的欧姆挡粗测该导电材料沿AC方向的电阻。机械调零、欧姆调零后,选择“挡”,按正确的操作步骤测量电阻,表盘的示数如图2所示,则该导电材料沿AC方向的电阻约为
。
(2)实验小组还想更精确地测量该导电材料沿AC方向的电阻,可供选择的实验器材如下:
A.电源(电动势,内阻不计)
B.定值电阻()
C.定值电阻()
D.电流表(量程
,内阻
)
E.电流表(量程
,内阻
)
F.滑动变阻器(阻值范围为
,允许通过的最大电流为
)
G.足量的导线与开关
为使实验误差尽可能小,要求电表的测量值在满偏值的以上,定值电阻应选用
”或“
”)。利用虚线框中电路图精确测量电阻
,在电路图中标明器材符号
(3)实验中测得两电流表、
的示数分别为
和
,可得电阻
(4)要测量该导电材料的电阻率还需要测量该导电材料的
![](https://img.xkw.com/dksih/QBM/editorImg/2023/3/19/8d38233f-689a-41f0-9b6e-a01c9a2cb802.png?resizew=465)
(1)用毫米刻度尺测量接入电路中的金属丝的有效长度L,再用螺旋测微器测量金属丝的直径D,如图甲所示,则
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9a6d85799453899836bc34ad276ec80e.png)
(2)该同学接着用欧姆表粗测该金属丝的电阻,他进行了如下操作:先用“
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d55519bd96aba05e6f1533ddc7bb63fa.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/aaf3a1e976dc7ccea4600a8ad1121760.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/eebdb972b35aaa81a6662aaf8db1c282.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/67c1313842b62428737610b14806d883.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cffa35373ec4e4684107b42adb7a5161.png)
(3)若用伏安法测量该金属丝的阻值,电路如图丙所示。除电源(电动势为4V,内阻不计)、电流表A(量程为30mA,内阻约
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d941822843eff28c70023ea38051c307.png)
A.电压表
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/48fade4e14bf5845ff14f9e95bb6bfef.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0ad53b547e11f3e4719a70a4b9564cc8.png)
B.电压表
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b40f1d184152aa3954752ed70e7d1612.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c94435abd92f9e157066cfb7f4e1b514.png)
C.滑动变阻器
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9efc18a5bb2e53586331b2a58538a48b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3268ee21400e819481400197ea8dc736.png)
D.滑动变阻器
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/19f20f21a9d50b61dac519a3ddab539d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/db2d4775108dbaaf447c51fe18b088c8.png)
(4)若某次测量中,电压表和电流表示数分别为U和I,请用上述直接测量的物理量(D、L、U、I)写出金属丝的电阻率
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/171102a883b22fe6ca578efc8926f5b8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b30db97c39edcede2f0e7d4e075fecec.png)
(1)数据分析。打点计时器在随物体做匀变速直线运动的纸带上打点,纸带的一部分如图甲所示,B、C、D为纸带上标出的连续三个计数点,相邻两计数点之间还有四个计时点未标出。若打点计时器所接交流电源的频率为
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b72e1aa573e51d8c2aea247529b69bd9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/380bbacf854e30e2e747fc286d2b9997.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bf15322699ee692781e91e11ee58b91b.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/2/18/74545740-3499-44d9-a98d-eebb4341b00d.png?resizew=411)
(2)实验原理。用橡皮筋、细绳套和弹簧测力计完成“探究两个互成角度的力的合成规律”实验。若A、B两同学根据实验数据分别作出的力的示意图如图乙和丙所示,则
![](https://img.xkw.com/dksih/QBM/editorImg/2023/2/18/f3b43632-0d7c-41bd-b648-384d0205df12.png?resizew=260)
(3)实验仪器。用螺旋测微器测量某金属丝的直径,若示数如图丁所示,则该金属丝的直径为
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/21f3bf70722b22983c120d008d097602.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/2/18/a0d6b927-6bdb-44c3-993b-bf7b74f5900e.png?resizew=172)
(1)用螺旋测微器测量吸管的直径,测量数据如图甲所示,则
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9a6d85799453899836bc34ad276ec80e.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/3/16/c5397e5e-b271-4ceb-b112-0363efa0b565.png?resizew=279)
(2)用毫米刻度尺测出接入电路中的吸管长度
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e566bad16f727c20b0c1dbabb90a3ec8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d55519bd96aba05e6f1533ddc7bb63fa.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/eebdb972b35aaa81a6662aaf8db1c282.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/aaf3a1e976dc7ccea4600a8ad1121760.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cffa35373ec4e4684107b42adb7a5161.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/3/16/736b652f-9bb9-469c-a7ff-935370cca338.png?resizew=338)
(3)其他实验器材有:
A.电源E(电动势为
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ec6ec06bd32883db9b4ea250b06d4313.png)
B.滑动变阻器(总阻值约为
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5d757a8853133814c9a9753443c1cf82.png)
C.电压表(量程为
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b383457dadfc62b6d16e22467ce48dd2.png)
D.电流表(量程为
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/39e26041fbb5ca7b1017e8dea923a2e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0b132e0cbd0e446630f4bb65804ce581.png)
E.开关K,导线若干。
利用上述实验器材设计电路,其中滑动变阻器应选用
(4)正确连接好电路,进行实验测量,将待测果汁两端的电压和流经它的电流记录在表格中如下:
次数 | 1 | 2 | 3 | 4 | 5 |
![]() | 0.16 | 0.28 | 0.48 | 0.55 | 0.78 |
![]() | 0.10 | 0.20 | 0.30 | 0.40 | 0.50 |
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4e43cca5751eff3d24b64cb51006d6d7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b30db97c39edcede2f0e7d4e075fecec.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/04bd482c8aa483cd59b4c22636960fe0.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/3/16/85f44ed5-9124-48e2-a2cb-0485f58a311e.png?resizew=328)
6 . 小李同学在“测定金属的电阻率”实验中。
(1)因电表内阻未知,用如图甲所示的电路来判定电流表该内接还是外接。正确连线后,合上开关S,将滑动变阻器的滑片P移至合适位置。单刀双掷开关K掷到1,电压表的读数U1=1.65V,电流表的示数如图乙所示;将K掷到2,电压表和电流表的读数分别为U2=1.75V,I1=0.33A.由此可知应采用电流表
(2)完成上述实验后,小李同学进一步尝试用其他方法进行实验:
此时所用测量仪器均已校准。待测金属丝接入电路部分的平均长度为50.00cm。
①用螺旋测微器测量金属丝的直径如丙图所示。
②用伏安法测金属丝的电阻Rx,实验所用器材为:电池组(电动势3V,内阻约1Ω)、电流表、电压表、滑动变阻器R(0~20Ω,额定电流2A)、开关、导线若干。小李同学利用以上器材正确连接好电路,进行实验测量,记录数据如下:
次数 | 1 | 2 | 3 | 4 | 5 | 6 | 7 |
U/V | 0.10 | 0.30 | 0.70 | 1.00 | 1.50 | 1.70 | 2.30 |
I/A | 0.020 | 0.060 | 0.160 | 0.220 | 0.340 | 0.460 | 0.520 |
图丁是测量Rx的实验器材实物图,图中已连接了部分导线,滑动变阻器的滑片P置于变阻器的一端。请根据上述表格的实验数据,补充完成图丁中实物间的连线
③小李同学在坐标纸上建立U、I坐标系。如图戊所示,图中已标出了与测量数据对应的坐标点。描绘出UI图线。由图线得到金属丝的阻值Rx可以估算出金属丝电阻率约为
A.1×10-2Ω·m B.1×10-3Ω·m C.1×10-6Ω·m D.1×10-8Ω·m
![](https://img.xkw.com/dksih/QBM/editorImg/2023/3/5/868a2b30-be1e-4b78-ba87-5da470f3e29e.png?resizew=98)
(1)用螺旋测微器测量金属丝的直径,示数如图所示,可得金属丝直径的测量值d=
(2)实验中除开关、若干导线之外还提供下列器材:
A.待测金属丝
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ce2581ae160692cd7e2686226fe5e2c6.png)
B.电源(电动势3V,内阻不计)
C.电流表
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a18722354086c42e62334983fc50eb6a.png)
D.电流表
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c9e65b2e896a5c2371ef4d17d58d2709.png)
E.灵敏电流计G(满偏电流
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e2e64be02afecfa2ad4aadf27d29ef3f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b0a8da8589c913fcfc1fcb2572c6eceb.png)
F.滑动变阻器(0~10Ω,允许通过的最大电流为1A)
G.电阻箱
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/be9b4a83b9aebebf29de0c4406ebf894.png)
①为了测量金属丝两端的电压,需要对电表进行改装得到一个量程为0~3V的电压表,则选择的器材为
②用所给的器材设计一个电路图,要求测量范围大一些,且测量尽量准确。
(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/78aa8e890d2ac882e0fe79598811777a.png)
A.电源E(电动势为
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/781884d55a55b3574cafbf362d2b3a59.png)
B.电压表V(量程为
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9cd1fc5aefd9457c7ae9fa5acbcdcdd1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/813431bcf2e3dcda7c2139e646811bd6.png)
C.电流表A1(量程为
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4b5c929172bbfc21741fa7ef1f53b7bb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/910928687da37388715dd531939fbfed.png)
D.电流表A2(量程为
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9a9d332743ec267382cd99600b757cd3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/47367bf5c848198638bc6d92ebe37262.png)
E.滑动变阻器R2(最大阻值
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/77a6041c88c8701ce1068b611f27aa4a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6699c896d7394a071917fe3922f3864f.png)
(1)用游标卡尺测得该材料的长度L如图甲所示,读数
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fd1846e964fd60c54888a3c706a97442.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9a6d85799453899836bc34ad276ec80e.png)
(3)设测得导电材料的电阻为R,导电材料的长度为L,导电材料的直径为D,求得导电材料的电阻率为
![](https://img.xkw.com/dksih/QBM/editorImg/2023/2/12/4b8393ae-2906-4714-a61c-a2979d020203.png?resizew=551)
(1)用螺旋测微器测量金属丝的直径,其中某次测量结果如图甲所示,则金属丝的直径d=
(2)在用欧姆表“×10”挡粗测金属丝电阻值时,在规范操作下,发现欧姆表指针偏转角较小,因此需重新选择
(3)改用如图丙所示电路测量该金属丝的阻值。在开关闭合前滑动变阻器的滑动端应置于图中的
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b30db97c39edcede2f0e7d4e075fecec.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/2/12/e2640119-0430-4fb5-94e7-72ce9cf6361d.png?resizew=177)