一理想变压器的原线圈连接一只交流电流表，副线圈接入电路的匝数可以通过触头Q调节，如图所示。在副线圈两输出端连接了定值电阻R0和滑动变阻器R，在原线圈上加一电压为U的交流电，则
A．保持Q位置不动，将P向上滑动时，电流表的读数变大
B．保持Q位置不动，将P向上滑动时，电流表的读数变小
C．保持P位置不动，将Q向上滑动时，电流表的读数变大
D．保持P位置不动，将Q向上滑动时，电流表的读数变小
BC
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| Liu Ying is my twin sister. We 1 black hair and round faces. We like 2 pop music. But 3 some ways, we look different. She has 4 hair than me. When my parents' friends come to our home, Katrina often sits on the sofa and says 5 , but I like to talk with them. So you can see she's much 6 than me. Katrina likes reading, drawing and cooking. I just like swimming and running. She has 7 more hobbies than me, but she is not as athletic 8 me. Because Katrina studies very hard, she does better than 9 at school. My parents often say to me, "Although Katrina is only 20 minutes younger than you, you 10 learn from her." | ||||
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