An object is 2m from a lens which forms an erect image one-fourth (exactly) the size of the object. Determine the focal length of the lens. What types of lens is this?

An object placed at 20 cm from a lens, forms an image on a screen placed 60 cm on the other side of the lens. What is the focal length and type of the lens ?

A convex lens of focal length 16 cm forms a real image double the size of the object. The image distance of the object from the lens is

A convex lens forms a real and inverted image of a pencial at a distance of 60 cm from the lens. The image formed is of the same size as the object. Find the focal length and power of the lens. At what distance is the pencil placed from the lens. ?

A convex lens forms a real and inverted image of a pencil at a distance of 40 cm from the lens. The image formed is of the same size as the object Find the focal length and power of the lens. At what distance is the : object placed from the lens?

A convex lens of focal length f produces a virtual image n times the size of the object. Then the distance of the object from the lens is

A convex lens forms a real image of pencil at a distance of 50 cm from the lens . The image formed is of the same size as the object . Find the focal length and power of the lens. At what distance is the pencil placed from the lens ?