如图 1-1-11所示,有一垂直纸面向里的匀强磁场, B = 0.8 T,磁场有明显的圆形边界,圆心为 O ,半径为 1 cm.现在纸面内先后放上圆线圈 A 、 B 、 C ,圆心均在 O 处, A 线圈的半径为 1 cm,10 匝; B 线圈的半径为 2 cm,1 匝; C 线圈的半径为 0.5 cm,1 匝 .问: (1)在 B 减为 0.4 T的过程中, A 和 B 中磁通量改变多少? (2)在磁场转过30°角的过程中, C 中磁通量改变多少?
【简答题】A.Fashions change overtime. B.Men are thriftier than women. C.Skirts and shoes are more important than other clothing. D.Some clothing may suit all occasions.
【单选题】听力原文: There are so many things going on in our modern lives, and change happens so quickly. It is hard to imagine a time when things were slower and you could really see a new thing come into your lif...