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33.一部單相220V\/110V變壓器之滿載負載實驗時,負載為純電阻,測得一次側電壓與電流分別為220V與10A,功率因數接近1,二次側電壓與電流分別為110V與19A,則此變壓器之滿載效率約為多
問題詳情
33.一部單相220V/110V變壓器之滿載負載實驗時,負載為純電阻,測得一次側電壓與電流分別為220V與10A,功率因數接近1,二次側電壓與電流分別為110V與19A,則此變壓器之滿載效率約為多少?
(A)98%
(B)95%
(C)85%
(D)80%
參考答案
答案:B
統計:A:0,B:2,C:0,D:0,E:0
難度:計算中
上一篇 :
32.一部他激式電動機之速度控制實驗,輸出轉矩固定,磁場繞組電壓固定、激磁電流不變,當電樞電壓接上200V時,測得轉速為1500rpm,若將電樞電壓調整為180V時,則測得之轉速約為多少 rpm? (
下一篇 :
34.用三部22.8kV\/380V、100kVA單相變壓器接成Δ-Δ接線之三相變壓器,當有一台單相變壓器故障時,下列敘述何者錯誤? (A)總輸出容量為173kVA (B)二次側線電壓為380V (
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