関連ワード:  what is the work done by frictional force    what is the nature of work done by frictional force    what is the formula of work done by frictional force    what is the sign of work done by frictional force    what is work done against frictional force    the work done by frictional force on a pencil    the work done by frictional force on a surface in drawing a circle    the work done by frictional force on a pencil in drawing a complete circle    the work done by frictional force on a surface    the work done by frictional force on an object moving on a rough surfaces  
結果 : what is the work done by frictional force