社群介绍：
<table style="border-collapse: collapse; width: 449.27pt;" border="0" width="599" cellspacing="0" cellpadding="0"><colgroup><col style="width: 449.25pt;" width="599" /> </colgroup>
<tbody>
<tr style="height: 14.25pt;">
<td style="height: 14.25pt; width: 449.25pt;" width="599" height="19">基础知识之磁与磁路感应（一）</td>
</tr>
</tbody>
</table>
