【简答题】将区间改写成集合(-∞,-3)=____________________
【判断题】理想电流源的输出电流是一个与端电压和电流的正方向,但不能规定电动势的方向。()
【单选题】We ran to the trees, ___ we couldn't see any more monkeys.
【单选题】It was so dark that we couldn't see each other 's faces .
【单选题】We couldn't see _____ because the light in the room was poor. [ ]
【简答题】电动势的单位与电压单位相同,也是伏特(V)。电动势是一个标量,同电流一样也有自己的规定方向,即规定:自负极通过 ________ 到正极的方向为电动势的方向。
【单选题】We couldn't see_____ because the light in the room was poor.
【单选题】It was do dark that we couldn't see each other 's faces .
【判断题】电动势的方向与电压一样,都是从正极指向负极( )