题目

Because of modern (技术), we have a much higher standard of living. 答案：【1】technology如图所示，理想变压器的初、次级线圈分别接着定值电阻R1、R2，且R1=R2，初、次级线圈的匝数比n1∶n2=2∶1，交流电源电压为U，则（    ）A.R1两端的电压为                        B.R1两端的电压为 C.R2两端的电压为                       D.R2两端的电压为