Question

A building is 6m high, and it is 80m from a converging camera lens. If the camera forms an image which is 6 mm high, (a) What is the magnification? (b) How far must the camera film be behind the lens for the image to be formed

Answer 1

Answer:

An object is placed at a distance of 12cm from a convex lens of focal length 8cm. Find nature of the image.

Explanation:

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.