Question

the magnification of an image formed by a lens is -1. if the distance of the image from optic centre of the lens is 25cm, where is the object placed? find the nature and focal length of the lens.

Answer 1

Answer:

The object is placed at the center of curvature.

Concave lens

Image is real inverted and of the same size

Explanation:

m= -( v/u)

Therefore=> - 1= - 25/u => u = 25

Focal length =uv/(u-v)

=25*25/(25+25)

=25*25 /50

=12.5 cm ans