問題詳情
17.自耦变压器铁芯上只绕有一个线圈，原、副线圈都只取该线圈的某部分，一升压式自耦调压变压器的电路如图所示，其副线圈匝数可调。已知变压器线圈总匝数为1900匝；原线圈为1100匝，接在有效值为220V的交流电源上。当变压器输出电压调至最大时，负载R上的功率为2.0 kW。设此时原线圈中电流有效值为I1，负载两端电压的有效值为U2，且变压器是理想的，则U2和I1分别约为
(A).380V和5.3A
(B).380V和9.1A
(C).240V和5.3A
(D).240V和9.1A
(A).380V和5.3A
(B).380V和9.1A
(C).240V和5.3A
(D).240V和9.1A
參考答案
答案：B
難度：適中0.5
統計：A(0),B(0),C(0),D(0),E(0)
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