A frame of reference is a coordinate system with a time scale used by the observer to describe the kinematic variables of an object. The velocity of object A relative to the observer B is given by the vector difference of their velocities relative to the ground G. The measured velocity is the relative velocity. For an observer standing on the ground, a man walking on a moving walkway appears to move faster. But for a woman standing on the walkway, the man appears to move, but slower. If the velocity of the man relative to the walkway is 1 meter per second, and the velocity of the walkway relative to the ground is 2 meters per second, what will be the velocity of the man relative to the ground? Initially, list the known and unknown quantities. Next, write the relative velocity equation connecting the reference frames. Finally, substitute the known values to solve for the unknown.