An erect image 2.0 cm high is formed 12 cm from a lens, the object being 0.5 cm high. Find the focal length of the lens.

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.

A convex lens of focal length 0.10 misused to form a magnified image of an object of height 5 m placed at a distance of 0.08 m from the lens. Calculate the position, nature and size of the image.

A convex lens of focal length 6 cm is held 4 cm from a newspaper which has print 0.5 cm high. By calculation, determine the size and nature of the image produced.