Question

An object is placed at a distance of 15 cm from a convex lens of focal length 20 cm. List four characteristics (nature, position, etc.) of the image formed by the lens.

Answer 1

Here, object distance, u = -15 cm

and focal length, f = 20 cm

Using lens formula,

`1/f = 1/v − 1/u`

`1/20 = 1/v − 1/(−15)`

`1/v = 1/20 − 1/15`

`v = − 60 cm`

Four characteristics of the image formed by the lens are :

(i) Image formed is virtual

(ii) Image is erect

(iii) Image is formed on the same side of the lens as the object

(iv) Enlarged image