A.3 B.2 C.4 D.5
A.有磁阻就一定有磁通 B.有磁通就一定有磁通勢 C.有磁通勢就一定有磁通 D.磁導(dǎo)率越大磁阻越大
A.歐姆定律 B.楞次定律 C.焦耳定律 D.法拉第電磁感應(yīng)定律
