由于线圈本身的电流变化而在本线圈中引起的电磁感应称为自感。
参考答案：对
Stephen Hawking believes that the earth is unlikely to be the only planet _life has developed gradually.
A．that
B．where
C．which
D．whose
A．a为动滑轮，B端钢缆受到滑轮组的拉力大小约为3G
B．a为动滑轮，B端钢缆受到滑轮组的拉力大小约为G
C．a、c为动滑轮，B端钢缆受到滑轮组的拉力大小约为3G
D．a、c为动滑轮，B端钢缆受到滑轮组的拉力大小约为G
G
G