如图所示，电源电压保持不变，R1是个定值电阻，R2是滑动变阻器，S2为单刀双掷开关，假设灯泡L的电阻不变，下列说法正确的是_刷题宝

题干

如图所示，电源电压保持不变，R₁是个定值电阻，R₂是滑动变阻器，S₂为单刀双掷开关，假设灯泡L的电阻不变，下列说法正确的是（　　）

A：S₁断开，S₂掷到1，滑片P向左移动，电流表A示数变大

B：S₁断开，S₂掷到1，滑片P向右移动，电压表V₁和V₂示数之和变大

C：S₂掷到2，S₁由闭合到断开，电压表V₂与电流表A示数之比变小

D：S₂掷到2，S₁由闭合到断开，电流表A示数变小，灯泡L亮度不变

上一题下一题 0.0难度选择题更新时间:2019-07-16 01:37:30

答案(点此获取答案解析）

A,D

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