当接在电感两端的直流电源突然断开时，其电感上感应出的电压大小

搜题请搜索小程序“爱下问搜题”

问题单项选择题

当接在电感两端的直流电源突然断开时，其电感上感应出的电压大小及方向的变化是（）.

A.大于电源电压幅值，方向相同

B.等于电源电压幅值，方向相反

C.小于电源电压幅值，方向相同

D.小于电源电压幅值，方向相反

答案

参考答案：B

听力题

小题1:After the hard work, I felt very t________.

小题2:He won a g______ medal in the 2012 London Olympics.

小题3:I have two f__________ friends. One is Japanese, and the other is American.

小题4: We open the window every day to let the fresh a______ in.

小题5:The skirts here are all beautiful. I don’t know which one I should c________.

小题6:The flu s___________ quickly in crowded places.

名词解释

或然性原则