P. 4812. There is a point-like light source \(\displaystyle T\) on the principal axis of a converging lens at a distance of \(\displaystyle d\) from the lens. There is a plane mirror on the other side of the lens opposite to the lens. The mirror is perpendicular to the principal axis.
\(\displaystyle a)\) If the mirror is moved along the principal axis, then the image of the light source, formed by the system, always coincides with the light source. How can this happen?
\(\displaystyle b)\) The distance between the light source and the lens is doubled. Where should the mirror be placed in order that parallel light rays leave the system.
Deadline expired on 10 March 2016.