Physics
In each of the following cases, where must an object be placed in front of a convex lens so that the image formed is,
(a) at infinity,
(b) of same size as the object,
(c) inverted and enlarged,
(d) upright and enlarged?
Answer
(a) In order to form the image at infinity, the object should be placed at focus, in front of a convex lens.
(b) In order to form the image of same size as the object, the object should be placed at 2F, in front of a convex lens.
(c) In order to form an inverted and enlarged image, the object should be placed between F and 2F, in front of a convex lens.
(d) In order to form an upright and enlarged image, the object should be placed between optical centre and focus, in front of a convex lens.
Related Questions
In the diagrams below, XX' represents the principal axis, O the optical centre and F the focus of the lens. Complete the path of the rays A and B as they emerge out of the lens.
(a)
(b)
Distinguish between a real and a virtual image.
A lens forms an upright and magnified image of an object.
(a) Name the lens.
(b) Draw a labelled ray diagram to show the image formation.
Complete the following table —
Type of lens Position of object Nature of image Size of image Convex Between the optical centre and focus Convex At focus Concave At infinity Concave At any distance