问题
问答题
如图所示,一小木块从斜面上滑下,在粗糙的水平面上滑动一段距离后便停下来.请你画出木块在水平面上滑动时的受力示意图.

答案
重心在物体的中心,过重心沿竖直向上、竖直向下以及水平向左的方向分别表示出支持力F、重力G和摩擦力f; 如图所示.
如图所示,一小木块从斜面上滑下,在粗糙的水平面上滑动一段距离后便停下来.请你画出木块在水平面上滑动时的受力示意图.
重心在物体的中心,过重心沿竖直向上、竖直向下以及水平向左的方向分别表示出支持力F、重力G和摩擦力f; 如图所示.
从下面方框中选择一个适当的词或短语,并用其适当形式填空,并将其正确形式写在答题卡对应位置。
小题2:Our school held a _______ sports meet last week. 小题3:The weather in the south is _______ (wet) than that in the north. 小题4:Many students can’t look after _______ (they) without the help of their parents. 小题5:We should eat more vegetables and _______ meat. 小题6:Maria is interested in ___________. 小题7:The traffic here is very busy and it’s _______ for children to walk alone. 小题8:My friend ____________her parents when I knocked at the door. 小题9:My book is_______, I can’t find it. 小题10:The good news brings me _______. |