A convex lens produces an inverted image magnified three times of an object placed at a distance of 15 from it. Calculate the image distance.

Calculate the focal length of a convex lens which produces a virtual image at a distance of 60 cm of an object placed 20 cm in front of it.

An object is placed at a distance of 100 cm from a converging lens of focal length 50 cm.

(i) What is the nature of image?

(ii) What is the position of image?

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.