题干

用图所示的光电管研究光电效应的实验中,用某种频率的单色光a照射光电管阴极K,电流计G的指针发生偏转.而用另一频率的单色光b照射光电管阴极K时,电流计G的指针不发生偏转,那么(   )

A:a光的波长一定大于b光的波长

B:增加b光的强度可能使电流计G的指针发生偏转

C:用a光照射光电管阴极K时通过电流计G的电流是由d到c

D:只增加a光的强度可使通过电流计G的电流增大

上一题 下一题 0.0难度 选择题 更新时间:2012-10-31 07:26:29

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D

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