Question

An object of height 5 cm is placed at a distance of 12 cm from a convex lens of focal length 8 cm. The position, nature and height of the
image respectively will be...?​

Answer 1

Focal length of convex lens,  f=8 cm

Object distance,  u=−12 cm

Using lens formula      

v

1

​  

−  

u

1

​  

=  

f

1

​  

 

where v is the image distance.

∴    

v

1

​  

−  

−12

1

​  

=  

8

1

​  

 

⟹ v=+24 cm

(+ve sign indicates that image is formed behind the lens)

Hence the image formed is real and inverted.