题干

图甲为远距离输电示意图,升压变压器原副线圈匝数比为1:100,降压变压器原副线圈匝数比为100:1,远距离输电线的总电阻为100Ω.若升压变压器的输入电压如图乙所示,输入功率为750kw.下列说法中正确的有(   )

A:用户端交流电的频率为50Hz

B:用户端电压为250V

C:输电线中的电流为30A

D:输电线路损耗功率为180kW

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答案(点此获取答案解析)

A,C

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    Attention from strangers is nothing new to me. Questions about my height is the center of almost every public interaction. My friends say my height is just a physical quality and not a personality aspect. However, when I reflect on my life, I realize that, my height has shaped my character in many ways and has helped to make me who I am.

    I learned how to be kind. When I was younger, some parents in my neighborhood regarded me kind of dangerous because I was so much larger than other children my age. I had to be extra welcoming and gentle simply to play with other children. Of course, now my coaches wish I weren't quite so kind on the basketball court.

    I learned the quality of not being too proud about myself. At 7 feet tall, everyone expects me to be an amazing basketball player. They come expecting to see Dirk Nowitzki, and instead they might see a performance more like Will Ferrell(successfully starred a professional basketball player). I have learned to be modest and to work even harder than my fellows to meet their (and my) expectations.

    I developed a sense of lightheartedness. When people playfully make fun of my height, 1laugh at myself too. On my first day of high school, a girl dropped her books in a busy hallway. I got down to her level and gathered some of her notebooks. As we both stood up, her eyes widened as I kept rising over her. Astonished, she dropped her books again. Embarrassed, we both laughed and picked up the books a second time.

    All of these lessons have defined me. Looking back, I realize that through years of such experiences, I have become a confident, expressive person. Being a 7-footer is both a blessing and a curse, but in the end, accepting who you are is the first step to happiness.