【摘要】 掷铁饼场地中线的方向与落地区距离的长短、安全有密切关系。如何确定掷铁饼场地的方向 ,前人未作论述。用数学几何的证明提出h =r/k公式 (现行田径竞赛规则常数K =3/5 =0 6 )。在场地纵轴上 ,从圈圆心到纵轴的垂足起 ,丈量直角边h ,以确定中线与纵轴的交点 ,连接圈圆心与交点 ,以确定中线的方向 ,按此方向安装护笼即能得到一个从圆心过护笼开口两端点至直段内突沿的两条相等的理论安全线和落地区有足够距离的掷铁饼场地。更多还原

【Abstract】 The direction of central line of discus ground is closely related to the length of sector and the safety of the athletes.There have been no discussions on how to decide the direction of central line of the discus ground.This paper puts forward h=r/k formula with proofs of the geometry (present norm:K=3/5=0 6).Starting from the center of the circle to the vertical line of the vertical axis,we measured the right angle side h in order to decide the joint of the central line and the vertical axis and to connect the center of the circle with the joint in order to decide the direction of the central line.To fix the enclosure according to this direction,tow equal safe lines from the center through two tips of the enclosure at the mouth to the edges of the straight line are got and enough space for throwing within the sector is ensured.更多还原