A wave front __________ is a surface on which all points of the wave are in the same phase of motion. A ray is __________ parallel to the velocity of the wave. When diffuse reflection from a surface occurs, __________ the reflected rays are not parallel to each other. A friend is standing 2 m in front of a plane mirror. You are standing 3 m directly behind your friend. Rays of light coming from the sun (a very distant object) are near and parallel to the principal axis of a concave mirror. The rays __________ will cross at the focal point. Light rays that are near and parallel to the principal axis of a concave mirror converge to a point. Rays of light emanate from a real image, but only appear to do so from a virtual image. Only a concave mirror can produce an enlarged image, provided the object distance is less than the radius of curvature.