問題詳情
19．下表给出了一些金属材料的逸出功。 
现用波长为400nm的单色光照射上述材料，能产生光电效应的材料最多有几种？（）(普朗克常量h=6.6×10-34J·s，光速c=3.00×108m/s)
(A)．2种
(B)．3种
(C)．4种
(D)．5种
现用波长为400nm的单色光照射上述材料，能产生光电效应的材料最多有几种？（）(普朗克常量h=6.6×10-34J·s，光速c=3.00×108m/s)(A)．2种
(B)．3种
(C)．4种
(D)．5种
參考答案
答案：A
難度：適中0.5
統計：A(0),B(0),C(0),D(0),E(0)
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