球面截痕：平面与球体交线的立体几何演示
2020-07-08 10:07
本 GeoGebra 范例演示平面与球体相交时形成的截痕（交线）。通过 Sphere、Plane、IntersectPath 等命令构造球体与截面，展示空间解析几何中球面截痕的核心性质：当平面与球体相交时，交线恒为一个圆，其半径随平面到球心距离的增大而减小。范例包含球体、截面圆、正交辅助线、多边形及角度标注等几何元素，并设有交互按钮与动态点，便于用户拖动平面或调整球体位置，实时观察截痕形状与大小的变化规律，适用于立体几何与空间解析几何的教学与探究。
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