空心螺线管中通以稳恒电流I,环内磁感应强度为<img src="https://zk.995w.com/lqwvjeImg/e4/e442c543943929fca1ffd5026cbf0816.png"style="width:26px;height:32px;">,当充满磁介质后,保持电流不变(忽略自感),磁感应强度为<img src="https://zk.995w.com/lqwvjeImg/c8/c80dfaeae739a217c0998a9c60ab34fc.png"style="width:21px;height:22px;">,则( )。<br>·<img src="https://zk.995w.com/lqwvjeImg/c8/c80dfaeae739a217c0998a9c60ab34fc.png"style="width:21px;height:22px;">一定大于<img src="https://zk.995w.com/lqwvjeImg/e4/e442c543943929fca1ffd5026cbf0816.png"style="width:26px;height:32px;"><br>·<img src="https://zk.995w.com/lqwvjeImg/c8/c80dfaeae739a217c0998a9c60ab34fc.png"style="width:21px;height:22px;">一定小于<img src="https://zk.995w.com/lqwvjeImg/e4/e442c543943929fca1ffd5026cbf0816.png"style="width:26px;height:32px;"><br>·<img src="https://zk.995w.com/lqwvjeImg/c8/c80dfaeae739a217c0998a9c60ab34fc.png"style="width:21px;height:22px;">一定等于<img src="https://zk.995w.com/lqwvjeImg/e4/e442c543943929fca1ffd5026cbf0816.png"style="width:26px;height:32px;"><br>·当磁介质是铁磁质时必有<img src="https://zk.995w.com/lqwvjeImg/c8/c80dfaeae739a217c0998a9c60ab34fc.png"style="width:21px;height:22px;">一定远大于<img src="https://zk.995w.com/lqwvjeImg/e4/e442c543943929fca1ffd5026cbf0816.png"style="width:26px;height:32px;">