题目1A. <img src="https://tihai-oss-cloud.itihey.com/img/4e9e68c9280686f0044382757bc57492.PNG">B. 铁磁质的相对磁导率µr >>1, 且为常数C. <img src="https://tihai-oss-cloud.itihey.com/img/119137fa91357a8af108fed4411fed28.PNG">D. <img src="https://tihai-oss-cloud.itihey.com/img/deb2682196077f4791d10522a8adf3ac.PNG">