![](https://img.xkw.com/dksih/QBM/2022/4/8/2953611748925440/2953843581894656/STEM/97945c98-5095-435f-a4a4-e74204474425.png?resizew=472)
(2)如图所示为多用电表的刻度盘。若选用倍率为“×100”的电阻挡测电阻时,表针指示如图所示,则:
![](https://img.xkw.com/dksih/QBM/2022/4/8/2953611748925440/2953843581894656/STEM/1e83e1ae-a7f3-4272-9007-a794af308a38.png?resizew=312)
所测电阻的阻值为
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0047f659c182291c84c224df6b5e993f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0047f659c182291c84c224df6b5e993f.png)
(3)某实验小组做实验描绘一只小灯泡L(额定电压为3.8V)的伏安特性曲线,做实验之前,先用欧姆表测量其内阻约为10
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0047f659c182291c84c224df6b5e993f.png)
A.电压表V1(0~3V,内阻为3k
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0047f659c182291c84c224df6b5e993f.png)
B.电压表V2(0~15V,内阻未知)
C.电流表A(0~0.6A,内阻约为2
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0047f659c182291c84c224df6b5e993f.png)
D.定值电阻R1=2k
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0047f659c182291c84c224df6b5e993f.png)
E.定值电阻R2=15k
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0047f659c182291c84c224df6b5e993f.png)
F.滑动变阻器R(0~10
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0047f659c182291c84c224df6b5e993f.png)
G.直流电源(6V,内阻不计),开关和导线若干。
①为了使测量更加精确,实验中的电压表选择
②请根据所选器材在图示方框内画出满足实验要求的电路图,并标明所选器材的代号
![](https://img.xkw.com/dksih/QBM/2022/4/8/2953611748925440/2953843581894656/STEM/dc13b415-bd4a-477c-a77b-bae327b074b7.png?resizew=248)
相似题推荐
![](https://img.xkw.com/dksih/QBM/2022/5/3/2971409503125504/2972095115304960/STEM/8cab8155-579b-4c3a-99fb-f78638a47a30.png?resizew=324)
(1)乙图螺旋测微器所示的小球的直径d=
(2)实验
(3)当方程式
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/5/4fac9067-1194-4de5-97c6-88a1341d9722.png?resizew=245)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/5/cea6db71-4c17-4a24-8560-1a2406bf9bed.png?resizew=138)
(2)为了测量某一未知电阻
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ce2581ae160692cd7e2686226fe5e2c6.png)
A.电源,电动势E=3.0V
B.电压表
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/46ad1a9cd19361d1f7a2340d76d50c80.png)
C.电压表
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4c688d3183cdee79c0ce7d84a23a38c4.png)
D.电流表
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/acf35aa115963656d885b6440d6caa2c.png)
E.电流表
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c9e65b2e896a5c2371ef4d17d58d2709.png)
F.滑动变阻器
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9efc18a5bb2e53586331b2a58538a48b.png)
G.滑动变阻器
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/19f20f21a9d50b61dac519a3ddab539d.png)
H.开关S、导线若干
在用伏安法测量该电阻的阻值时,要求尽可能准确,并且待测电阻两端的电压从零开始连续调节,则在上述提供的器材中电压表应选
(3)请在虚线框内画出用伏安法测量该电阻阻值时的实验电路图
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/5/65763b4a-c054-4ccb-ae92-a86c396518a8.png?resizew=214)
(4)请根据电路图将下列实物图补充完整
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/5/0fd976e2-8edb-4115-91bc-691050f9e41d.png?resizew=281)
【推荐3】在做测定金属的电阻率的实验中,若待测电阻丝的电阻约为5Ω,要求测量结果尽量准确,备有以下器材:
A.电池组(3V,内阻r=1Ω)
B.电流表(0~3A,内阻约0.0125Ω)
C.电流表(0~0.6A,内阻约0.125Ω)
D.电压表(0~3V,内阻约4kΩ)
E.电压表(0~15V,内阻约15kΩ)
F.滑动变阻器(0~20Ω,允许最大电流1A)
G.滑动变阻器(0~2000Ω,允许最大电流0.3A)
H.开关、导线
(1)上述器材中应选用的是
(2)在本实验中,某同学用螺旋测微器和游标卡尺测该电阻丝的直径d和长度L如下图,则用螺旋测微器测金属棒直径为
(3)接通开关,改变滑动变阻器滑片P的位置,并记录对应的电流表示数I,电压表示数U。
(4)用实验过程中测量的物理量对应的字母表示电阻率,则该电阻丝电阻率的表达式为ρ=
①用天平分别测出物块A、B的质量4m0和3m0(A的质量含遮光片)。
②用游标卡尺测得遮光条的宽度d如图乙所示,则遮光条的宽度d=
③将重物A,B用轻绳按图甲所示连接,跨放在轻质定滑轮上,一同学用手托住重物B,另一同学测量出挡光片中心到光电门中心的竖直距离h,之后释放重物B使其由静止开始下落。测得遮光片经过光电门的时间为∆t,则此时重物B速度vB=
(2)要验证系统(重物A,B)的机械能守恒,应满足的关系式为:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/442257676ca155e57db46b636bd32845.png)
直流电源:电动势4V,内阻可不计;
电流表
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/024e2379c58191758f8bd7602a6bcb9f.png)
电流表
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b34a75c2a392f235c5f07b91d9fb58d5.png)
电压表V:量程0~3V,内阻约3kΩ;
滑动变阻器
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9efc18a5bb2e53586331b2a58538a48b.png)
滑动变阻器
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/19f20f21a9d50b61dac519a3ddab539d.png)
开关、导线等。
(1)从甲中读出金属丝的直径
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9a6d85799453899836bc34ad276ec80e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9a6d85799453899836bc34ad276ec80e.png)
(2)在所给的可供选择的器材中,应选的电流表是
(3)本实验应选择电流表
(4)补全实物图,要求:导线不能交叉;
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ce2581ae160692cd7e2686226fe5e2c6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b30db97c39edcede2f0e7d4e075fecec.png)
(2)某同学利用机械能守恒原理
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c92ca27b2f57fe5f4f18bda2ae6285f0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/80b53eab97158937f92039c1e133b0f1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f285174fbf90a9742de57c1e53224cff.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e8e8854159e7443b5fe53436bf9e367f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f40eb362809c6568da7584877c431ae5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b248332648d96a11df8bf37b945ded90.png)
A.c可能是计数时每次都误将49次全振动记为50次 |
B.图线a对应的g值小于图线b对应的g值 |
C.a可能是每次都误将悬点到小球下端的距离记为摆长L |
![](https://img.xkw.com/dksih/QBM/2020/1/9/2373445518417920/2374308414316544/STEM/e80eb108-52b9-46f9-aed1-88d8c756fcde.png?resizew=468)
(2).某同学用伏安法测定待测电阻Rx的阻值(约为10 kΩ),除了Rx,开关S、导线外,还有下列器材供选用:
A.电压表(量程0~1 V,内阻约10 kΩ) B.电压表(量程0~10 V,内阻约100 kΩ)
C.电流表(量程0~1 mA,内阻约30 Ω) D.电流表(量程0~0.6 A,内阻约0.05 Ω)
E. 电源(电动势12 V,额定电流2 A,内阻不计)G.滑动变阻器R0(阻值范围0~10 Ω,额定电流2 A)
①为使测量尽量准确,电压表选用
②在答题卡上画出测量Rx阻值的实验电路图:
![](https://img.xkw.com/dksih/QBM/2020/1/9/2373445518417920/2374308414316544/STEM/57a078a2-62bb-44e1-8fd4-3425862879bc.png?resizew=200)
③该同学选择器材、连接电路和操作均正确,从实验原理上看,待测电阻测量值会
![](https://img.xkw.com/dksih/QBM/2017/2/28/1633763011698688/1637280852975616/STEM/c6e669d4-5b7a-4c71-b0b2-3e2c5d787f01.png?resizew=210)
A.学生电源:直流稳压(电压6 V,额定电流0.6 A)
B.电流表A1(0~0.6 A~3 A,内阻约1 Ω、0.5 Ω)
C.电流表A2(0~100 mA,内阻约10 Ω)
D.电压表V(0~3 V~15 V,内阻约1 kΩ、3 kΩ)
E.螺旋测微器
F.电阻箱R1(0~999.9 Ω,1 A)
G.电阻箱R2(0~9 999 Ω,1 A)
H.单刀双掷开关S一只
(1)选择适当的器材,要求能较准确地测出Rx和电流表内阻RA的值,在虚线框内已经画出设计好的电路图,并标明了所选器材代号,简要说明电流表为什么选A2;
(2)根据给出的设计,简要说明实验步骤,写出Rx和电流表内阻RA的表达式:
A.
B.
C.Rx=
A.待测滑动变阻器
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ce2581ae160692cd7e2686226fe5e2c6.png)
B.电流表
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/024e2379c58191758f8bd7602a6bcb9f.png)
C.电流表
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b34a75c2a392f235c5f07b91d9fb58d5.png)
D.电压表
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/48fade4e14bf5845ff14f9e95bb6bfef.png)
E.电压表
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b40f1d184152aa3954752ed70e7d1612.png)
F.滑动变阻器R,全电阻约20Ω
G.直流电源E,电动势3V,内阻不计
H.游标卡尺
I.毫米刻度尺
J.电键S导线若干
(1)用伏安法测定
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ce2581ae160692cd7e2686226fe5e2c6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/024e2379c58191758f8bd7602a6bcb9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b34a75c2a392f235c5f07b91d9fb58d5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/48fade4e14bf5845ff14f9e95bb6bfef.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b40f1d184152aa3954752ed70e7d1612.png)
(2)画出测量电路的原理图,并根据所画原理图将下图中实物连接成测量电路。
(3)为了进一步测量待测量滑动变阻器电阻丝的电阻率,需要测量电阻丝的直径和总长度,在不破坏变阻器的前提下,请设计一个实验方案,写出所需器材及操作步骤,并给出直径和总长度的表达式。
需要的器材:
操作步骤:
直径:
![](https://img.xkw.com/dksih/QBM/2010/8/13/1575049103327232/1575049138716672/STEM/4c54a322-a0bb-4048-98d2-8009fb83839e.png?resizew=202)
![](https://img.xkw.com/dksih/QBM/2010/8/13/1575049103327232/1575049138716672/STEM/22ac1054-b36a-4861-b878-f022804ad1a6.png?resizew=222)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/9/29/c8325151-8b1a-4b00-b1a1-13396290f4f9.png?resizew=183)
(1)图(a)中的A端表盘插孔写
(2)根据题给条件可得R1=
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6496f55810a059cb2da407feaad1db04.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0c841e3b1c64a0088b96b18d422db2d8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8c29a7e8eea08197bf53164a560bee58.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/eebdb972b35aaa81a6662aaf8db1c282.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0c841e3b1c64a0088b96b18d422db2d8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cffa35373ec4e4684107b42adb7a5161.png)
(2)适当调节
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6496f55810a059cb2da407feaad1db04.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0c841e3b1c64a0088b96b18d422db2d8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6496f55810a059cb2da407feaad1db04.png)
(3)依次将
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/18b5acf59efb00b5fe33327b9e0f8494.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b52b4f24969673c863b5aff4fb6751ce.png)
次数 | 1 | 2 | 3 | 4 | 5 | 6 |
砝码质量 | 0.0 | 0.5 | 1.0 | 1.5 | 2.0 | 2.5 |
电压 | 0 | 57 | 115 | 168 | 220 | 280 |
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6d9a21728ff5ec164b3030bd11392841.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b519e5794ef9932b64715619adf860db.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bd2ce588d378b2943bb0451f6b54e48b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b519e5794ef9932b64715619adf860db.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cad135b14c9dcd83eab6618d7694c7b0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f07cc78053b232e92d9cdb59f8deee04.png)
(5)若在步骤(4)中换用非理想毫伏表测量
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8c29a7e8eea08197bf53164a560bee58.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f5076289823db419f94e9c0c8f4aafd9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bd2ce588d378b2943bb0451f6b54e48b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f5076289823db419f94e9c0c8f4aafd9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b519e5794ef9932b64715619adf860db.png)
(1)某同学先用多用电表测量,选择了“×1 k”挡位,并进行了欧姆调零.测量时发现指针指在如下左图所示位置,则应该换
![](https://img.xkw.com/dksih/QBM/2017/2/16/1625344718282752/1630353892753408/STEM/f80cb4574cf14584acc029a17d2dabf0.png?resizew=368)
(2)为了进一步精确地测量该电阻的阻值,该同学用伏安法测电阻.现有如下实验器材:
A.电流表A1(量程0.6 A,内阻0.2 Ω)
B.电流表A2(量程3 mA,内阻20 Ω)
C.电压表V1(量程6 V,内阻约2 kΩ)
D.电压表V2(量程15 V,内阻约12 kΩ)
E.滑动变阻器R
F.电源E(电动势4 V)
G.开关S及导线若干
为了尽量减少误差,电流表选
(3)该同学已完成了部分电路图,请帮助他完成剩余部分.
![](https://img.xkw.com/dksih/QBM/2017/2/16/1625344718282752/1630353892753408/STEM/7343fe4daf0144c5939fd5b47407ee5b.png?resizew=250)