如图所示,水平虚线
、
之间是匀强磁场,磁场方向水平向里,磁场高度为
。竖直平面内有一等腰梯形线框,线框的质量为
,底边水平,其上下边长之比为
,高为
。现使线框
边在磁场边界
的上方
高处由静止自由下落,当
边刚进入磁场时加速度恰好为0,在
边刚要进入磁场前的一段时间内,线框做匀速运动,重力加速度为
,求:
(1)
边刚进入磁场时的速度
的大小;
(2)在
边刚要进入磁场前,线框做匀速运动的速度
的大小;
(3)从线框开始下落到
边刚进入磁场的过程中,线框中产生的热量
。
![](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/3eabd5f3a86afe49dcd70571e2b96cfd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/294f5ba74cdf695fc9a8a8e52f421328.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/771f4d980ae7c47a692797f3994efae5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15752847ab476edec45450680887baa8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/172722d11ea7e01411fa06dbb82f46ee.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/73465a1f9aa03481295bf6bd3c6903ac.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9e52a8f07834cbbbe4224962672fbbb2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/276509f01529d982ab21e479a4619268.png)
(1)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f44c235d8b49207ad3f2d77dc5d6cf20.png)
(2)在
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9e52a8f07834cbbbe4224962672fbbb2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/814f55724f7ee57bd395eb3b95393c68.png)
(3)从线框开始下落到
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9e52a8f07834cbbbe4224962672fbbb2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/acc290b44635265137fdf13146b6a6d9.png)
![](https://img.xkw.com/dksih/QBM/2020/12/26/2622646538674176/2624777598164992/STEM/b2a43ad68c644eb0ac6e6b607ce81f2e.png?resizew=233)
更新时间:2020-12-29 19:46:36
|
【知识点】 求线框进出磁场时电阻上生热
相似题推荐
解答题
|
适中
(0.65)
【推荐1】如图所示,足够长的间距
的平行光滑金属导
、
固定在水平面内,左端连接一个阻值
的定值电阻,导轨间存在一个宽度
的匀强磁场区域,磁感应强度大小为
,方向如图所示。一根质量
,阻值
的金属棒a以初速度
从左端开始沿导轨滑动,穿过磁场区域,金属棒始终与导轨垂直且接触良好,导轨电阻不计,求:
(1)金属棒a刚进入磁场时所受安培力的大小;
(2)金属棒a穿过磁场过程中通过回路的电荷量;
(3)金属棒a穿出磁场时的速度;
(4)金属棒a穿过磁场过程中电阻R上产生的焦耳热。(此问结果保留两位有效数字)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8dc8ec343f3ef653d766c6a3241ae6f9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411461db15ee8086332c531e086c40c7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7a5f1641947153c80b987320885a2b57.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/281daf740a8ffd2c64652caf47ea5d81.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/58d6961838f6bd0917fe95735d7c53dc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4468e92eda1761771f3fa39a416b9fd4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ccc94f2ea411c691d91a4fc6665c24ce.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9fef7ab7166b566761cb79353e7fb88d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1d2a037e97d9c91e080844e111bc3183.png)
(1)金属棒a刚进入磁场时所受安培力的大小;
(2)金属棒a穿过磁场过程中通过回路的电荷量;
(3)金属棒a穿出磁场时的速度;
(4)金属棒a穿过磁场过程中电阻R上产生的焦耳热。(此问结果保留两位有效数字)
![](https://img.xkw.com/dksih/QBM/2022/5/2/2977853460439040/2979192663400448/STEM/cceda6de-29e8-4a08-9425-ae11253c0040.png?resizew=298)
您最近一年使用:0次
解答题
|
适中
(0.65)
【推荐2】如图所示,宽
、长
的矩形闭合线框
,电阻为
,线框以速度
垂直于磁场方向匀速通过匀强磁场区域,匀强磁场宽
,磁感应强度
,问:
![](https://img.xkw.com/dksih/QBM/editorImg/2022/9/3/13f52966-f385-43bf-8ea0-779f61294439.png?resizew=122)
(1)
边进入磁场后,它所受到的磁场力多大?
(2)整个过程中线框产生的热量是多少?
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c29b08b992c5ceb3bb100089f53c75e8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/aabff8f0bf8de7b74e2afbccc545e7ac.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/35893041a02be39c9d0c1e9b329556eb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f170a0904fd9872e2d1e1918c727c053.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/785bb089dfef418d777ab042f56cbf5a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4caccca18d49c06b4d0188b3f1de77b8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b802d2c2db8db4f1f65480513be9ec5b.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/9/3/13f52966-f385-43bf-8ea0-779f61294439.png?resizew=122)
(1)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/69225cfdfbc0a9a1ccfdd15c46353b8f.png)
(2)整个过程中线框产生的热量是多少?
您最近一年使用:0次