题目

滑动变阻器是靠改变连入电路中电阻线的 来改变电阻的；要改变灯泡的电流，变阻器应与灯泡 联。 答案：【答案】长度、串【解析】试题分析：滑动变阻器是靠改变连入电路中电阻线的长度来改变电阻的；要改变灯泡的电流，变阻器应与灯泡串联。Mr Wu is writing reports about his students. Help him complete the following sentences. (1)Molly always makes lots of mistakes in her Maths homework, she is very________.