関連ワード:  the work done against the frictional force on a surface    the work done by the frictional force on a surface    the work done by the frictional force on a surface in drawing    the work done by the frictional force on a surface in drawing a circle    the work done by the frictional force on a surface in drawing a circle of radius r    how does friction affect work done    what is the work done by frictional force    what is work done against friction  
結果 : the work done against the frictional force on a surface