PHYSICS · Multi-part · CBSE · Physics · Ray Optics and Optical Instruments · Ray Optics and Optical Instruments
Problem
In a photographic enlarger, the negative (object) and the photographic paper (screen) are fixed 150cm apart on a common axis. The enlarger lens is required to project an image that is 5 times larger than the negative onto the paper.
(i) Determine the distance of the negative from the lens so that the required enlargement is obtained.
(ii) Find the corresponding distance of the image from the lens.
(iii) Calculate the focal length of the lens that must be chosen.
(iv) State whether the image on the photographic paper will be erect or inverted and give a brief reason.