問題詳情
2. 發光二極體(LED)是新型的半導體元件，可藉由施加電壓將元件內的電子激發。當這些被激發的電子回復至其原狀態時，便可發光。最近科學家已能製作出可發白光的 LED。白光 LED 具有發熱量低、耗電量小、壽命長、可封裝成帄面光源等優點，有可能逐步取代一般較為耗費能量的傳統光源，成為未來照明設備的主流。下表是白光 LED 光源與傳統照明光源的耗電功率與發光效率之比較。 
根據上表，若欲使 2000 年所產製的白光 LED，發出相當於一個功率 15 W 白熾燈泡的照度，試問約需幾個這種白光 LED﹖
(A) 35 個
(B) 60 個
(C) 85 個
(D) 115 個
(E) 145 個。
根據上表，若欲使 2000 年所產製的白光 LED，發出相當於一個功率 15 W 白熾燈泡的照度，試問約需幾個這種白光 LED﹖(A) 35 個
(B) 60 個
(C) 85 個
(D) 115 個
(E) 145 個。
參考答案
答案：D
難度：適中0.5
統計：A(0),B(0),C(0),D(0),E(0)
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