题干

如图所示的是示波管工作原理图:电子经电场加速后垂直射入偏转电场,若加速电压为U1,偏转电压为U2,偏转电场的极板长度与极板间的距离分别为L和d,取“单位偏转电压引起的偏转距离”来描述示波管的灵敏度(该距离越大则灵敏度越高),则下列哪种方法可使示波管的灵敏度提高(  )

A:增大U1

B:增大U2

C:减小L

D:减小d

上一题 下一题 0.0难度 选择题 更新时间:2018-04-25 10:40:39

答案(点此获取答案解析)

D

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