If a torque is applied to the disk in such a fashion that the axis of the torque is the same as that of rotation of the disk, the direction of the former will be parallel to AB.
如果力矩是这样地作用于一圆盘上,即力矩的轴与圆盘的旋转轴方向一致,则力矩的方向与ab线平行。
2
AB inverse direction with coordinate azimuth coordinates.