题目

小金想测量某滑轮组提起物体时的机械效率。 (1) 请帮小金完成滑轮组的绕线,要求向下拉动绳端时,物体上升; (2) 小金应当 (选填“匀速”或“加速”)向下拉动弹簧秤,若物体重G1 , 弹簧秤读数F1 , 则该滑轮组的机械效率ƞ=; (3) 小金想进一步探究物重大小对该滑轮组的机械效率有何影响,请帮他设计实验方案,简述你的设计思路。Frank 去年来到泰中学习。在校学习期间,他对学校提倡的“创建和谐校园”活动感触颇深。请你以他的名义,给远在美国的父母写一封信,介绍学习的现状并谈谈感受。创建和谐校园学生之间和谐发展学习刻苦,兴趣广泛,友爱互助……老师学生和谐相处学生尊敬老师;老师严格要求学生;师生关系融洽……人与环境和谐共存爱护花草树木,保持环境卫生,不随地乱扔废弃物……个人感想……要求:1、表达清楚、语法正确、上下文连贯。 2、要点必须包括所有相关信息,并作适当发挥,但不得出现真实班级、姓名等。 3、词数:100词左右(信的开头与结尾已给出,不记入总词数)。 4、参考词数:respect尊敬;build up建立,创建;a harmonious campus和谐校园; impress 给……留下印象 Dear Mum and Dad, Time flies! I’ve been here for nearly a year. I’m very pleased to find that our school is really a good one. The students in our school                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             
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