What is axis of pure rotation?
The concept of axis of of pure rotation ( or instantatious center of rotation) is a bit confusing. The text books in engineering mechanics( Irvin shames , Beer & Johnston etc) tells that the locus of points in a body, which is (are) having zero veloity. This fits well in case of a 2D motion. As a limiting case of this we are assuming the center of rotation is at inifinity for a rigid body moving in a straight line