At what distance should an object be placed from a convex lens of focal length 12 cm to obtain an image at 24 cm from it on the other side? What will be the magnification produced in this case?

A converging lens of focal length 10 cm is placed at a distance of 20 cm from a screen. How far from the lens should an object be placed so as to form its real image on the screen?

An object 10 cm high is held 25 cm away from a converging lens of focal length 10 cm. find the position, size and nature of the image formed. Also draw the ray diagram.

An object 3 cm tall is placed on the axis of a convex lens of focal length 5 cm at a distance of 10 m from the optical center of the lens. Find the nature, position and size of the image formed. Which case of image formation by convex lenses is illustrated by this example?

The filament of a lamp is 80 cm from a screen and a converging lens forms an image of it on a screen, magnified three times. Find the distance of the lens from the filament and the focal length of the lens.