题目

灯泡L1、L2标有“6V 3.6W”字样，灯泡L3、L4标有“6V 6W”字样；把四个灯泡按如图所示连入电路中都发光，那么最亮的灯泡是_______，最暗的灯泡是_______。 答案：【答案】L1L2【解析】试题分析：如图所示，灯泡L2和L3并联，电压相等，电阻越小，实际功率越大，灯泡L3的电阻较小，所以灯泡L3比灯泡L2亮；灯泡L1与灯泡L4是串联的，通过的电流相等，当电流相等时，电阻越大，实际功率越大，所以灯泡L1的电阻较大，实际功率较大，所以灯泡L1比灯泡L4要亮；灯泡L3It was a rainy morning and the children, mainly boys with various learning difficulties, refused to settle for the start of the lesson. As an inexperienced teacher, I tried every means to get them to be ______, but in vain. my panic was rising and I could feel my heart beating wildly. This was the ______ of my job as a music teacher, I thought -- teaching was not for me. Then I had an idea. Hoping that no one would notice that I was ______ inside, I threw my voice as far as it would reach: "Put your heads on the desks and close your ______! We are going on a journey."____, the children fell silent. "Now what should I do?" I thought to myself. Reaching over to my collection of CDs, I blindly took one out, put it in the machine and played it.Obediently (顺从地), my class lay their heads on their desk, closed their eyes and _____. When the music started, the room as filled with the most beautiful tones and musical colors I could have ever imagined. All the children were ______. When the music finished, I asked them all to raise their _______ slowly so that we could share our musical journey.At this point, when all the children were willing to share their experiences, I began to learn how to ______. The music allow me to learn that teaching is about sharing and respect, tears and smiles, the knowing and the ______ and most of all, an understanding of each other. This was the power that music in the classroom could have.1.A. glad B. safe C. kind D. quiet2.A. end B. aim C. rule D. plan3.A. guessing B. shaking C. responding D. laughing4.A. eyes B. mouths C. books D. doors5.A. Punctually B. Importantly C. Amazingly D. Obviously6.A. slept B. nodded C. waited D. continued7.A. talking B. singing C. dancing D. listening8.A. legs B. heads C. arms D. shoulders9.A. teach B. imagine C. play D. understand10.A. unprepared B. unspoken C. unknown D. unforgotten