level 5
1.光是粒子,那么用频率教长的光去撞击频率较短的光(可能是反了,频率没学好)那么光子的速度会快一点吗?但是又好像同是光速,速度一样撞不了?(高一)2.如图,质量为0.4kg的小球从距离地面高度H=4m的A处自由下落到地面,恰好沿着R=0.5m的半圆形槽运动,到最低点C处时的速率为8m/s,后沿着圆弧运动,脱离槽后竖直向上运动最高升到B处,若小球在弧形槽上运动时受到的阻力大小不变,g=10m/s2``````````````````````````````````````````A。求小球到达最低点是的动能```````````````````！小球在最低点时受到的支持力多大?````````````！小球离槽后上升高度h````````````````````````！``````````````````B`````````````````````````````````````````H`！``````````````````！```````````````````````````````````````````！````````````````h`！```````````````````````````````````````````！``````````````````！~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~``````````````````````！~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~（凑合着看这里是圆弧）~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~C。空格坏了，````表示空格~~~~~~表示地面！！！表示下落轨迹
2007年07月07日 01点07分
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