Ray coming from an object situated at infinity, fall on a convex lens and an image i
Channel: Doubtnut
Date: 2020-08-30

Ray coming from an object situated at infinity, fall on a convex lens and an image is formed at a distance of 16 cm from the lens. When a concave lens is kept in contact with the convex lens, the image is formed at a distance of 20 cm from the lens combination. Calculate the focal length of the concave lens.