問題詳情
17.如图，一理想变压器原副线圈的匝数比为1：2；副线圈电路中接有灯泡，灯泡的额定电压为220V，额定功率为22W；原线圈电路中接有电压表和电流表。现闭合开关，灯泡正常发光。若用U和I分别表示此时电压表和电流表的读数，则 
(A)
(B)
(C)
(D)
(A)
(B)
(C)
(D)
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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