Question

An object is placed at a distance of 20cm from a convex lens and its real and inverted images of same size is formed on the screen placed on the other side of the lens. The focal length of the lens is​

Answer 1

Answer:

When an object is placed at the centre of curvature in front of a convex lens, its image is formed at the centre of curvature on the other side of the lens. The image formed is real, inverted, and of the same size as the object.