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如图所示装置由水平轨道、倾角θ=37°的倾斜轨道连接而成,轨道所在空间存在磁感应强度大小为B、方向竖直向上的匀强磁场.质量m、长度L、电阻R的导体棒ab置于倾斜轨道上,刚好不下滑;质量、长度、电阻与棒ab相同的光滑导体棒cd置于水平轨道上,用恒力F拉棒cd,使之在水平轨道上向右运动.棒ab、cd与导轨垂直,且两端与导轨保持良好接触,最大静摩擦力等于滑动摩擦力,sin37°=0.6,cos37°=0.8.

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    The entire house was lit with lights. It was Meera's wedding the next day. Seema walked to her daughter's bedroom. Meera was not there, so she left the envelope on Meera's bed and went away. When Meera came back after a bath downstairs, her eyes fell on the envelope. She picked it up and opened it Sitting on the bed, she started to read it:

    My darling daughter, I'm so happy for my darling is getting marked! To such a good man! At the same time, I'm a little worried, too. The reason? You're going to a new house where everything is going to be new: the people, relationships and surroundings. Yes, you're smart and Vinod will be there with you to help, but I have a few things to say:

    Accept Vinous parents as your parents. Remember that your mother-in-law will have her own understanding about you. So it's up to you give her a good impression.

    Earn respect from family members. If that means changing yourself a little bit and adapting to their customs, just do it. It will help you to settle into your new home.

    Never compare your mothers home and their home. It may not be appreciated.

    The kitchen is one place where small fights can appear. Ifs your mother-in-law s kingdom, so ask her permission if you want to cook something. If she offers help, accept it. This Ml help in building trust between you. Similarly, offer her your help when she s busy cooking. Thus, a new relationship -will be born: one of respect and understanding.

    Finally, respect your husband, as he's your life partner. Remember that a marriage re-quires trust, love and compromise (妥协).

    I could have sat with you and told you, but I felt that writing all this down would make you understand better and I'm sure you'll give your whole heart to this relationship. Remember that both Papa and I are here for you always.

Love,

Ma