题目

小金进行课外实验探究时,发现了一些有趣的实验现象,如图所示:①根据电路图,连接电路(钨丝由一个白炽灯除去玻璃罩制成); ②闭合开关S,小灯泡L发光,钨丝不发光; ③向钨丝吹气时,小灯泡L变亮,钨丝不发光; ④用酒精灯给钨丝加热,小灯泡L逐渐变暗直至熄灭,移除酒精灯后,小灯泡L逐渐恢复亮度。 下列分析正确的是( ) A . 步骤②可推得,通过钨丝的电流小于小灯泡L的电流 B . 步骤③可推得,钨丝的电阻增大了 C . 步骤④可推从A、B、C、D四个选项中,找出其划线部分与所给单词的划线部分读音相同的选项。1.complete                                                   A.president            B.honest                 C.recently               D.expensive2.among                                                                                       A.official               B.worry                 C.remove               D.mostly3.performed                 A.practiced           B.advanced           C.judged               D.operated[来源:Z。xx。4.orange                                                       A.celebrate            B.operate               C.candle                D.average 5.whole                                                                                        A.write                  B.whisper              C.wheel                 D.wheat
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