【如图所示,ab两端电压U不变,若cd两端接理想电压表,则示数为60V,若cd两端接理想电流表,则示数为3A,若cd两端接电阻R3,则R1、R2、R3上消耗的电功率相等.电阻R1、R2、R3的阻值分别为______】
<p>问题:【如图所示,ab两端电压U不变,若cd两端接理想电压表,则示数为60V,若cd两端接理想电流表,则示数为3A,若cd两端接电阻R3,则R1、R2、R3上消耗的电功率相等.电阻R1、R2、R3的阻值分别为______】<p>答案:↓↓↓<p class="nav-title mt10" style="border-top:1px solid #ccc;padding-top: 10px;">马士英的回答:<div class="content-b">网友采纳 cd端接电压表时:I=U(R1+R2),IR2=UR2R1+R2=60V①;cd端接电流表时:R2短路,I′=UR1=3A②;cd端接R3,功率相等,R2和R3并联:U2=U3,由P=U2R可得R2=R3,I1=I2+I3=2I3=2I2,由题意知三个电阻消耗的功率相等,由P=I2R...
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