如图所示,质量为m的物块与一轻弹簧相连后放在倾角为的粗糙固定斜面体上,轻弹簧的另一端与斜面顶端的固定挡板相连。当物块在B点时处于原长.现将物块移到A点,给其一个向上的初速度v0,物块刚好能向上运动到C点,AB=BC=L,已知重力加速度为g, ,则物块从A点运动到C点的过程中( )A. 物块运动到B点时速度最大B. 物块在A点释放时的加速度和上滑到C点时的加速度大小相等,方向相反C. 物块机械能的损失量为2(1-sinθ)mgLD. 物块与斜面间的动摩擦
指出错误并改正。
( )1. I and Jim are good classmates. A B C D ( )2. What is you father's last name? A B C D ( )3. Let's going to the park together. A B C D ( )4. This is their classrooms. A B C D ( )5. All of the boys are play basketball on the playground. A B C D
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