問題詳情
16.放射性物質衰變至僅剩原來一半量所需時間稱半生期，已知放射性物質的衰 變爲一級反應，其半生期爲定値，與濃度無關。今有一批含某一種放射性之鋼 筋，其中所含放射性物質的半生期爲一年，且衰變後即無放射性。則四年後剩餘的放射量爲原有的幾倍？ 
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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