A.2 B.3 C.4 D.5
A.10安 B.0.1安 C.1安 D.5安
A.有磁阻就一定有磁通 B.有磁通就一定有磁通勢(shì) C.有磁通勢(shì)就一定有磁通 D.磁導(dǎo)率越大磁阻越大