Question

A convex lens and a convex mirror of radius of curvature 20 cm are placed co-axially with the convex mirror placed at a distance of 30 cm from the lens. For a point object at a distance of 25 cm from the lens, the final image due to this combination coincides with the object itself. What is the focal length of convex lens ?

Answer 1

Explanation:

A convex lens and a convex mirror of radius of curvature 20cm are placed co-axially with the convex mirror placed at a distance of 30cm from the lens. For a point object at a distance of 25cm from the lens, the final image due to this combination coincides with the object itself.