时间:2017-07-17 07:16:50
1、选择题 由“嫦娥奔月”到“万户飞天”，由“东方红”乐曲响彻寰宇到航天员杨利伟遨游太空，中华民族载人航天的梦想已变成现实。“神舟”五号飞船升空后，先运行在近地点高度为200km、远地点高度为350km的椭圆轨道上，实施变轨后做匀速圆周运动，共运行了n周，起始时刻为t1，结束时刻为t2，运行速度为v，半径为
r，则计算其运行周期可用
[? ]
A.T=
B.T=
C.T=
D.T=
2、选择题 一个内壁光滑的圆锥形筒的轴线垂直水平面，圆锥筒固定，有质量相同的小球A和B沿着筒的内壁在水平面内做匀速圆周运动，如图所示，A的运动半径较大，则（ ? ）
3、填空题 如图所示是自行车传动装置的示意图，若脚蹬匀速转一圈需要时间T，已数出链轮齿数为48，飞轮齿数为16，要知道在此情况下自行车前进的速度，还需要测量的物理量是______（填写该物理量的名称及符号）．用这些量表示自行车前进速度的表达式为v=______．
4、选择题 有一物体沿旋转圆台匀速转动，圆半径为R，圆台与物体的最大静摩擦力是物重的style="shiti/data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAoAAAAlCAIAAAD0qu8JAAAAoElEQVQ4jd2Tuw0DMQxDuYXGUKEhbgo33uGGcOMRMoMbT5AV3GgDb8EUzvc+QZogh7B9IiEIFPhW+AS7ATHVDdxbFQB7mCTZo8r/YTdcZSFvunf1U7ynA6z2VSwAILX1UVnR2F/dPmlsrarGTjdIbY8BeMkW5jnMnfSSl+4cTHUajhxs0RkYJJczSa6SSUJvaSP5lJI/43taTXH9aQe++QWJN86PN/2ZpgAAAABJRU5ErkJggg==" alt="">．要使物体不打滑，那么圆台角速度的安全速度为（ ）
A．ω≤style="shiti/data:image/png;base64,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" alt="">
B．ω≤style="shiti/data:image/png;base64,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" alt="">
C．ω≥style="shiti/data:image/png;base64,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" alt="">
D.ω=style="shiti/data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAABQAAAAiCAIAAADQyG7qAAABGElEQVRIie2VvYHDMAiFtYXGUKEhPAUN29AwQmZQwyZu2IAtfAXRjx07US5FrjgqFf7ggcRz2D6I8A/3YMhhiAw8CzPkmNDqGUlmK9sqMURZrSXiom/BwQEtHEI+R69kC2Fr9oq8hLXwldSXsGGKL8uewoYp1WlpfpriCAthu6Saa5kfWNPs0e9sBn4jPobDr+Lrsv8qrIX3k+o3P1VZC4/e0B7sLNyWTAh3cBWWtZ4PjsUA/rX7RHOle2VbZQHWwhnYVom7TdJ81nCHhRCJANjPY2UtjCS+MAcndNgwpXRfPcMURxthWLzaw7ZuYdvb5aPmpQIHV+0Dazpd843IejtNqmGKY0dh2zuz/yi46DinMfXobd972z/Hrcj4gCA/RAAAAABJRU5ErkJggg==" alt="">
5、选择题 如图所示是健身活动器械“太极推柔器”上的两个圆环，两圆环在同一个平面内，能绕各自的轴O1、O2转动．健身的人手握环边缘上的把手a、b转动圆环，达到手臂关节活动的目的．今活动者手握把手，按图中标出的转动方向和角速度匀速转动圆环，在从图示位置开始的一周的转动中，关于两把手（质量相同，两圆环和把手关于cd对称）的有关情况，下列说法正确的是（ ）
A．两把手的线速度方向总是相反的
B．两把手的速度方向相同的时刻有四个
C．两把手加速度方向在一条直线上的时刻有两个
D．两把手所受合力大小相等