Reflection of light by a concave mirror

Principle

Parallel light beams can be so reflected by a concave mirror that the reflected beams intersect at a point in front of the mirror.

Benefits

• minimal preparation time
• light-intense halogen lamp
• easy teaching by using the demo board for demonstration
• ideal complement to analog student experiments by directly comparable devices

Tasks

Mark the object point at different distances from the vertex of the mirror (beyond or at the twofold focal length or between the single and twofold focal length; in the focal plane; within the focal length). Place the magnet-held lamp and light box, each with one-slit diaphragms, so that the beams successively pass through the marked points and are reflected by the mirror. While doing so observe the path of the rays after reflection.