Bill Potts wrote in USMA 10233: >Joe Reid wrote: >> The usual practice is to use the right-hand rule to determine the >> direction >> of the vector representing the rotation. Consider the z-axis to be the >> axis of rotation and the rotation to be such that the x-axis moves toward >> the y-axis. Then if the y-axis is considered to extend behind the x-z >> plane, the system is right-handed. If the y-axis is considered to extend >> in front of the x-z plane, the system is left-handed. >> >> I am sorry for this convoluted explanation. If I had you with me in the >> same room I could do better. In short, the direction of the vector >> representing the axis of rotation is determined by the direction of >> rotation according to the convention used by the mathematician. >> > >As I've said to others in this thread, Joe, my problem isn't with >understanding the above. It's something I learned almost 50 years ago. > >My problem was with your referring to the axis itself as a vector, when the >axis is only the directional component of the vector. Put it another way. The vector defines the direction of the axis.
