【单选题】在下列关于自感和位移电流的表述中,正确的是:
A.
自感系数的定义式为L=Φm/I,所以I越大,L越小
B.
自感是对线圈而言的,对直导线回路不存在自感问题
D.
位移电流是电荷的定向运动产生的,也能激发磁场
【单选题】—This book is a little hard. ________read something easier? —AIl right. [ ]
【简答题】Why are changes in prices hard to measure?
【判断题】自感是对线圈而言的,直导线不存在自感问题。
【判断题】逻辑函数 化简为最简与或式为F=C 。( )
【简答题】Why
was van den Bercken surprised by the music she found on
the Internet? (5.0分)A. She
didn’t know Handel wrote keyboard music . B. It
was extremely difficult to play.
【判断题】用PL实现逻辑函数时,首先将逻辑函数化简为最简与或式()