转动木板上木块的静摩擦力

The Static Friction on the Board of the Rotating Board

由三维转动的矩阵表示，得到连续两次转动后多边形板倾斜角的余弦值．对于边缘上一端固定后滚动的倾斜圆形木板，得到了倾斜角与转动角的解析关系；进而给出了两种木板上小木块静摩擦力的解析表达式．

The cosine of incline angle of a polygon board under two successive rotation is derived from the three dimensional matrix representation of rotation. The analytical relationship between incline angle and rotation angle is given for the rotational disk with an edge point fixed. Then the static force of a wood on these two kind of board are given analytically.