1 . 小明利用如图甲所示的电路,测量额定电压为2.5V的小灯泡的额定功率。电源电压为3V,滑动变阻器最大阻值为20Ω。
(1)请用笔画线代替导线将图甲的电路连接完整,要求:闭合开关后滑动变阻器的滑片向右滑时灯变亮
(2)在确认电路和器材无误后,小明开始进行实验,当滑动变阻器的滑片P移到某位置时,电压表示数如图乙所示,为了测出小灯泡的额定功率,他应将滑片P向
(3)小明在实验中移动滑片P时,突然小灯泡的灯丝烧断了,则电压表的示数将
(4)小明换用相同规格的小灯泡重新进行实验,实验结束后,他利用实验数据绘制了如图丙所示的图像。由图像可知:小灯泡的额定功率为
(5)小明做完实验后用如图丁所示的电路也测出了额定电压为2.5V的小灯泡的额定功率。已知定值电阻的阻值为R0,电源电压保持不变,请完成下列实验步骤:
闭合开关,移动滑片P,使电流表A2的示数为
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5d757a8853133814c9a9753443c1cf82.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2024/1/22/8d1242b9-cb54-4fa0-a31d-892b1759e956.png?resizew=607)
(1)在连接电路时,滑动变阻器的滑片P应移到
(2)连好电路,闭合开关,移动滑片P到某一位置时,电压表示数(如图乙所示)为
(3)王敏同学移动滑片P,记下多组对应电压表和电流表的示数,并给制成图丙所示的
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dd1fd3cc33190245791eddc26c629b9f.png)
(4)王敏的同桌丽丽认为不用电压表也可以测量小灯泡的额定功率,丽丽向老师要了一个阻值为
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/98749c62acf2448a2d8b6a8055d2a7c5.png)
①只闭合开关
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a454a2c91ace8ef50412a6adf91f8086.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/530f5b63e797195906285c0c03eb9276.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2f1ac49b4139636fb1809fe970b23a87.png)
②保持滑动变阻器滑片位置不变,
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2d1a0fd1ad044a9ecfcba672779bd678.png)
③小灯泡额定功率的表达式为
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1d7648e5363f4e448af38e52e4c682ab.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2024/1/13/dbd8e8ed-6911-4de7-8e84-8e69d436f1e2.png?resizew=688)
(1)用笔画线代替导线,将图-1中所示的器材连接成完整电路;
(2)电路连接正确后,闭合开关,小灯泡发光,此时电压表的示数为2.0V,为了测量小灯泡的额定电功率,这时应该向
(3)根据实验数据得到小灯泡
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dd1fd3cc33190245791eddc26c629b9f.png)
(4)实验小组根据小灯泡的
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dd1fd3cc33190245791eddc26c629b9f.png)
(5)在测量小灯泡电功率的实验过程中,电流表坏了,实验小组找来一只阻值合适的定值电阻
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/be9b4a83b9aebebf29de0c4406ebf894.png)
①断开
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d43eb0b274e00cbbc4a210da4165042.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/530f5b63e797195906285c0c03eb9276.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4c76eaa6628066e3bd985ca5945b5839.png)
②
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/530f5b63e797195906285c0c03eb9276.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d43eb0b274e00cbbc4a210da4165042.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b52b4f24969673c863b5aff4fb6751ce.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/df2542a7471f08320b0e2ccc3fe0b886.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4c76eaa6628066e3bd985ca5945b5839.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b52b4f24969673c863b5aff4fb6751ce.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/be9b4a83b9aebebf29de0c4406ebf894.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2024/3/2/d2942d1e-6c5a-4041-a81a-28e6fb2dc4f9.png?resizew=394)
(1)请你用笔画线代替导线,将实物电路连接完整
(2)实验中,小王同学连接好电路后,闭合开关,发现小灯泡不亮,且电压表无示数,电流表有示数,则故障的原因可能是
(3)故障排除后,闭合开关,移动滑动变阻器的滑片到某一点,电压表的示数如图所示,要测量小灯泡的额定功率,应将滑片P向
(4)某同学在实验中,不小心将滑动变阻器损坏(不能使用)了,一时又找不到其他变阻器。你能否利用身边的物品替代滑动变阻器完成该实验,说出你的做法:
(5)小红同学在实验结束与同学讨论时说:“该实验电路也可以用来研究电流与电压的关系”。小红的说法是否正确,为什么
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/49322e3ac2dff94f7d13c7f535e61118.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4d64b26bd3eaeebadf07fef49e260282.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2024/3/1/4c9b5792-9a44-4e80-8f3f-a74d7fa23896.png?resizew=329)
(1)本实验测量电功率的原理是
(2)闭合开关后,移动滑动变阻器的滑片,当滑动变阻器接入电路中的电阻变大时,电压表的读数也随着变大,发生这一现象的原因是
(3)电路检查无误后,闭合开关,移动滑动变阻器滑片P到某处,电压表示数为
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/de60a1d55b525f90366b7360dca983bc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/49322e3ac2dff94f7d13c7f535e61118.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/811ddb62dded70f279710ae6c0fdbb80.png)
(4)某兴趣小组的同学还想接着利用此电路探究电流与电阻的关系,于是将图甲中的小灯泡换成了
![](https://img.xkw.com/dksih/QBM/editorImg/2024/3/1/241d354b-83b1-4322-8d54-8727c2402c23.png?resizew=644)
(1)图-1是小明测量小灯泡额定功率的实验电路图,图中有一根导线连接错误,请在这根导线上打“×”,并在图中改正;
(2)在连接电路时,开关应处于
(3)闭合开关,移动滑片P直到电压表示数为2.5V,此时电流表示数如图-2所示,电流大小为
(4)该同学又设计了如图-3所示的测量电路,测量额定电压为
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/feaac21e2a7876602c16119c03f8e683.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/be9b4a83b9aebebf29de0c4406ebf894.png)
①闭合开关S,把开关
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/45b849494ea9d2a2417459713d32a432.png)
②保持滑动变阻器滑片位置不变,把开关
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/45b849494ea9d2a2417459713d32a432.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/be9b4a83b9aebebf29de0c4406ebf894.png)
③即可得出小灯泡的额定功率
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6283e5681784d1a97aea16bfb4a5b0a9.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2024/2/26/c159c021-abd4-4977-8dd1-980187f2a15a.png?resizew=487)
(1)如图甲所示,用毛皮摩擦过的橡胶棒靠近吸管的一端,发现它们互相排斥,说明吸管带的是
(2)如图乙所示,小明用A、B两个金属夹子将一根铅笔芯接入电路中,当B夹子左右移动时,小灯泡的亮度会发生变化,说明导体的电阻大小与
(3)在测量额定电压为2. 5V的小灯泡的电功率实验中,根据实验数据绘制出如图丙所示的I~U图像,则小灯泡的额定功率为
![](https://img.xkw.com/dksih/QBM/editorImg/2023/12/25/ded9a50f-f37e-4094-a906-ec96b6321072.png?resizew=210)
A.探究电流与电压的关系——保持 |
B.探究电流与 |
C.测量 |
D.测量 |
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/267feba236a22d3b0203270b9cee8abf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5b1dd08b7554f95138ccc039c8aa133.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/12/19/e9b0c727-09df-490f-80be-a97ca5af1ab6.png?resizew=528)
(1)根据实验要求连接的电路如图-1所示,闭合开关S,发现小灯泡不发光,电流表无示数,电压表有示数且超过量程,则电路故障可能是小灯泡
(2)排除故障后,同学们继续进行实验,记录的实验数据如下表,当电压表示数为
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5b1dd08b7554f95138ccc039c8aa133.png)
①小灯泡的额定功率为
②小灯泡的亮度随着实际功率的增大而
③小灯泡的灯丝电阻随着实际功率的增大而变大,其原因是小灯泡的灯丝电阻与
实验序号 | 电压U/V | 电流I/A | 电阻R/ | 电功率P/W | 小灯泡的亮度 |
1 | 1.5 | 0.24 | 6.25 | 0.36 | 较暗 |
2 | 2.5 | 正常 | |||
3 | 3.0 | 0.32 | 9.38 | 0.96 | 很亮 |
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cffa35373ec4e4684107b42adb7a5161.png)
(4)实验后同学们想测量另一个额定电压为
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4c76eaa6628066e3bd985ca5945b5839.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9efc18a5bb2e53586331b2a58538a48b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/be9b4a83b9aebebf29de0c4406ebf894.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/df2542a7471f08320b0e2ccc3fe0b886.png)
①闭合开关
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/910f1655703721b51006b887a2394b6d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/907d9bd02fd9c4257518438b2d24eb56.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/779629f16056a50f4c06e3996d8e1c82.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9fd5f9ecb870fedb5b9a608d9ca2f911.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f833a7beb83820ecede0234c671f1878.png)
②闭合开关
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/779629f16056a50f4c06e3996d8e1c82.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/910f1655703721b51006b887a2394b6d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/907d9bd02fd9c4257518438b2d24eb56.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/78cdfb19ccbde81ef1eae7ede2b961c9.png)
③不改变滑片P的位置,闭合开关
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/910f1655703721b51006b887a2394b6d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/779629f16056a50f4c06e3996d8e1c82.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/907d9bd02fd9c4257518438b2d24eb56.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1121190db07ad1d64015a3dc4873d65d.png)
④则待测小灯泡的额定功率的表达式:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1d7648e5363f4e448af38e52e4c682ab.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4c76eaa6628066e3bd985ca5945b5839.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9fd5f9ecb870fedb5b9a608d9ca2f911.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f833a7beb83820ecede0234c671f1878.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1121190db07ad1d64015a3dc4873d65d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/be9b4a83b9aebebf29de0c4406ebf894.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2024/2/10/17ca8440-d2a0-4aa6-9886-1703c2addf39.png?resizew=516)