时间:2019-06-23 21:32:44
1、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="">
2、实验题 一个有一定厚度的圆盘,可以绕通过中心垂直于盘面的水平轴转动,我们用电磁打点计时器、米尺、游标卡尺、纸带、复写纸来完成下述实验:(打点计时器所接交流电的频率为50Hz, A、B、C、D……为计数点,相邻两计数点间有四个点未画出)
①如图甲所示,将打点计时器固定在桌面上,将纸带的一端穿过打点计时器的限位孔,然后固定在半径为6cm的圆盘的侧面,当圆盘转动时,纸带可以卷在圆盘侧面上;
②接通电源,打点计时器开始打点,启动控制装置使圆盘匀加速转动;
③经过一段时间,停止转动和打点,取下纸带,进行测量。 
(1)由图丙可知,打下计数点D点时速度大小为________m/s,此时圆盘圆盘转动的角速度为______rad/s; 
(2)圆盘匀加速转动的过程中,纸带运动的加速度大小为_____________m/s2。
3、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
4、选择题 如图所示,倒置的光滑圆锥面内侧,有质量相同的两个小玻璃球A、B,沿锥面在水平面内作匀速圆周运动,关于A、B两球的角速度、线速度和向心加速度正确的说法是? (? )
A.它们的角速度相等ωA=ωB
B.它们的线速度υA<υB
C.它们的向心加速度相等
D.A球的向心加速度大于B球的向心加速度
5、选择题 不定项选择
小球做匀速圆周运动,半径为R,向心加速度为a,则( ? )
A.小球受到的合力是一个恒力
B.小球运动的角速度为
C.小球在时间t内通过的位移为
D.小球的运动周期为2π