问题 选择题
2002年诺贝尔物理学奖中的一项,是奖励美国科学家贾科尼和日本科学家小柴晶俊发现了宇宙X射线源.X射线是一种高频电磁波,若X射线在真空中的波长为λ,以h表示普朗克常量,c表示真空的光速,以E和m分别表示X射线每个光子的能量和质量,则(  )

A.E=,m=0

B.E=,m=

C.E=,m=0

D.E=,m=

答案

答案:D

写作题

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