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如图所示,两根足够长的光滑平行金属导轨MN、PQ间距为l=0.5m,其电阻不计,两导轨及其构成的平面均与水平面成30°角.完全相同的两金属棒ab、cd分别垂直导轨放置,每棒两端都与导轨始终有良好接触,已知两棒质量均为m=0.02kg,电阻均为R=0.1Ω,整个装置处在垂直于导轨平面向上的匀强磁场中,磁感应强度B=0.2T,棒ab在平行于导轨向上的力F作用下,沿导轨向上匀速运动,而棒cd恰好能够保持静止.g取10m/s2,求:

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阅读下面短文,按照句子结构的语法性和上下文连贯的要求,在空格处填入一个适当的词或使用括号中词语的正确形式填空。

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    “Get used to the speed. It makes New York feel slow.”

    Meanwhile, I am making friends from all over ____ world. My British friends share their Chinese experiences with me when we have afternoon tea at Sinan Mansions. Sometimes, I share my adventures ____ Russia with my American friends. We ____(attract) by global culture and ideas.

    I still remember the first time I met one of my best friends, Hans from Belgium. When he knew where I came from, he ____ (sudden) spoke in the Wenzhou dialect.

    That shocked me. He told me ____ he had many friends from Wenzhou, ____ he can speak a little “Wenzhou hua (dialect of Wenzhou)”.

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