天空中星星围绕着____旋转,北极星相对不动,是____产生的现象。
北极星
地球自转
如图所示,质量为m、带电量为﹣q的液滴从h高处自由下落,穿过A板的小孔进入匀强电场,到达B板时的速度刚好为零.设板间距离为d,不计阻力,则UAB=____,正极板是____.(空气阻力忽略不计)
人类和现在类人猿的共同祖先是( )
(2015•四川达州)—Excuse me, could you please tell me the way to the ? I have had too much water.—Go along the street and you will find one.